Portia

Cato the Elder
Portia (moon)
The Merchant of Venice

From Latin Porcia, a feminine form of the gens name Porcius (the gens of the Cato the Elder and his famous descendants), from porcus (“pig”). The moon is named for the character in The Merchant of Venice.

(astronomy) The seventh satellite of the planet Uranus.


subdwarf

Hertzsprung-Russell diagram
Hertzsprung-Russell diagram

(astronomy) A star that is dimmer than a main-sequence star of same temperature; located below the main sequence on the Hertzsprung-Russell diagram.


subgiant

(astronomy) A star that has left the main sequence but has not yet become a true giant star.


hypergiant

(astronomy) A star that is extremely massive and even more luminous than a supergiant.


liquid mirror telescope

en-noun

liquid mirror telescope (plural liquid mirror telescopes)

reflecting telescope
reflecting telescope

(astronomy) A type of reflecting telescope employing a parabolic liquid mirror made by spinning a pool of reflective liquid.


evection

evection (countable and uncountable, plural evections)

(astronomy) Modification of the lunar orbit due to the gravitational effects of the Sun.


Rosalind

From Proto-Germanic *hrussą (“horse”) and *linþaz (“soft; weak, tender”), associated by medieval folk etymology with Latin rosa linda "lovely rose".


LQG

LQG (countable and uncountable, plural LQGs)

large quasar group
large quasar group#English

(countable, astronomy) Initialism of large quasar group.


resurgent

en-adj

resurgent (comparative more resurgent, superlative most resurgent)

more resurgent (comparative)
most resurgent (superlative)

(astronomy) Of a celestial object, moving upwards relative to the horizon after a period of having moved downwards.


Wikipedia

Etymology tree
Proto-Polynesian *witi
Hawaiian wiki
Hawaiian wikiwikider.
English wikiblend.
Proto-Indo-European *h₁en-
Proto-Indo-European *h₁en-
Proto-Indo-European *h₁én
Ancient Greek ἐν (en)
Ancient Greek ἐν- (en-)
Proto-Indo-European *kʷel-
Proto-Indo-European *kʷékʷlos
Ancient Greek κύκλος (kúklos)
Proto-Indo-European *-yósder.
Ancient Greek -ιος (-ios)
Ancient Greek ἐγκύκλῐος (enkúklĭos)
Proto-Indo-European *peh₂w-der.
Proto-Hellenic *pā́wits
Ancient Greek παῖς (paîs)
Ancient Greek -εύς (-eús)
Ancient Greek -εύω (-eúō)
Ancient Greek παιδεύω (paideúō)
Proto-Indo-European *-éh₂
Proto-Indo-European *-i-eh₂
Ancient Greek -ία (-ía)
Ancient Greek παιδείᾱ (paideíā)
Ancient Greek ἐγκύκλιος παιδείᾱ (enkúklios paideíā)der.
New Latin encyclopaedīabor.
English encyclopediablend.
English Wikipedia
Blend of wiki + encyclopedia, coined by Larry Sanger in 2001.

etymon

(astronomy) A main-belt asteroid (No. 274301).


Dione

en-proper noun

Dione (countable and uncountable, plural Diones)

From Latin Diōnē (“of Jupiter”), from Ancient Greek Διώνη (Diṓnē, “of Zeus”).

(astronomy) A moon in Jupiter system, Solar System; The fourth largest moon of Saturn.


Serpentarius

From Latin, literally "serpent handler".

(astronomy, obsolete) A zodiacal constellation of the northern summer said to depict a man holding a serpent; the serpent is the constellation Serpens.


Bellatrix

(astronomy) A blue eruptive variable star, the third brightest star in the constellation Orion; Gamma (γ) Orionis.


Alnilam

From Arabic اَلنِّظَام (an-niẓām), related to the word نَظْم (naẓm, “string of pearls”).

(astronomy) A large blue star in the constellation of Orion; Epsilon (ε) Orionis, one of the three stars that form Orion's Belt.


Saiph

From Arabic سَيْف (sayf), originally سَيْف اَلْجَبَّار (sayf al-jabbār, “sword of the giant”).

(astronomy) A blue star in the constellation Orion; Kappa (κ) Orionis.


eternal recurrence

The concept dates from ancient times and was popularized by the philosopher Nietzsche (1844-1900).

(cosmology, religion, philosophy) The belief or theory that all the events in cosmic history repeat in an endless cycle.


eternal return

(cosmology, religion, philosophy) Eternal recurrence.


decoupling

[diːˈkʊpəlɪŋɡ]

Directly combining in a low energy state (ground state) is less efficient, so these hydrogen atoms generally form with the electrons still in a high-energy state, and once combined, the electrons quickly release energy in the form of one or more photons as they transition to a low energy state. This release of photons is known as photon decoupling.

2023 July 13, Wikipedia contributors, “Chronology of the universe”, in English Wikipedia, Wikimedia Foundation:

(cosmology) The emission of photons during Recombination.


Serpens Caput

Pseudo-Latin from Latin serpēns (“snake”) + caput (“head”). As genitive is often mentioned Serpentis Capitis and as translation is mentioned Serpent's Head (rarely Head of the Snake).

(astronomy) The western half of the northern constellation Serpens, said to resemble a snake. It is said to represent the head end of the snake.


Serpens Cauda

From Latin serpēns (“snake”) + cauda (“tail”).

(astronomy) The eastern half of the northern constellation Serpens, said to resemble a snake. It is said to represent the tail end of the snake.


moonlet

"A moonlet within the ring system will exert a systematic torque on ring material."

(astronomy) a very small body orbiting a planet, often as part of a planetary ring system.


X-ray binary

(astronomy) A binary star system in which one star of the pair is an optically invisible X-ray source.


starscape

(astronomy) A picture or view of a field of stars.


arachnoid

Mid 18th century borrowing from New Latin arachnoīdēs, from Ancient Greek ᾰ̓ρᾰχνοειδής (ărăkhnoeidḗs, “like a cobweb”), from ᾰ̓ρᾰ́χνη (ărắkhnē, “spider web”) + -ο- (-o-) + -ειδής (-eidḗs, “-oid, -like”). By surface analysis, arachn- + -oid.

der

ᾰ̓ρᾰχνοειδής

af

/əˈɹæk.nɔɪd/

(astronomy) A round network of fractures in the crust of Venus.


Helene

en-proper noun

Helene (countable and uncountable, plural Helenes)

From French Hélène and from German Helene. Doublet of Helen, Helena, and Elaine.

(astronomy) A moon of the planet Saturn.


heliosphere

The heliosphere isn’t really a sphere at all, more an elongated teardrop shape.

2023, Martin MacInnes, In Ascension, Atlantic Books, page 397:

(astronomy) The region of space where interstellar medium is blown away by solar wind; the boundary, heliopause, is often considered the edge of the Solar System.


primum mobile

en-noun

primum mobile (plural primum mobiles or prima mobilia)

primum mobiles (plural)
prima mobilia (plural)

From Middle English primum mobile (“outermost celestial sphere causing other spheres to move”), borrowed from Medieval Latin prīmum mōbile (literally “first mover”), a calque of Arabic مُحَرِّك أَوَّل (muḥarrik ʔawwal, “first mover”), which is itself a calque of Ancient Greek τὸ πρῶτον κινῆσαν (tò prôton kinêsan, “prime mover”).

ref

From Petrus Apianus, Gemma Frisius (1539) Petri Apiani cosmographia, per Gemmam Phrysium, apud Louanienses medicum ac mathematicum insignem, restituta: additis de adem re ipsius Gemmae Phry. libellis, ut sequens pagina docet, Antwerp: In pingui gallina Arnoldo Berckma[n]no [Arnold Birckmann], →OCLC.

calque

مُحَرِّك أَوَّل

der

τὸ πρῶτον κινῆσαν

But as there is a double motion of the stars, that is, under the primum mobile, and round the world, by both which, as we have said, they influence, we must consequently suppose, that the significators rule over things subjected to them by this twofold (or double) motion, to wit, under the primum mobile, and round the world.

[1814], Didacus Placidus de Titus [i.e., Placido Titi], “Theses, from the First Book of the Author’s ‘Celestial Philosophy’”, in John Cooper, transl., Primum Mobile, with Theses to the Theory, and Canons for Practice: Wherein is Demonstrated, from Astronomical and Philosophical Principles, the Nature and Extent of Celestial Influx upon the Mental Faculties and Corporeal Affections of Man; […], London: Printed and published by Davis and Dickson, […], →OCLC, paragraph 33, pages 12–13:

A primum mobile, therefore, being essential to the celestial mechanism, the same may be proved geometrically to originate in a solar repulsion, or in a repulsive force produced by whatsoever cause, and emanating spontaneously from the central luminary; [...]

1822, “the author of ‘Creation,’ a poem” [pseudonym], “Laws Tending to Demonstrate the Action of a Primum Mobile, or Solar Repulsion”, in Primum Mobile, or Solar Repulsion; being a Query Concerning the Primary Cause of Motion in the Solar System, as Connected with Gravity, Liverpool: Printed by James Smith, for the author, →OCLC, pages 243–244:

Dante [Alighieri] now mounts up from the Heaven of the fixed stars to the Primum Mobile, or Crystalline Heaven.

1867, Dante Alighieri, “Notes to Paradiso. [Canto XXVII.]”, in Henry Wadsworth Longfellow, transl., The Divine Comedy, Boston, Mass., New York, N.Y.: Houghton, Mifflin and Company. […], →OCLC, page 701, column 1:

The equinoctial was supposed to revolve, because it was the "girdle" of the primum mobile, and turned with it.

1872, “Additional Notes”, in Walter W[illiam] Skeat, editor, A Treatise on the Astrolabe; Addressed to His Son Lowys by Geoffrey Chaucer. 1391 A.D. Edited from the Earliest MSS., London: Published for the Chaucer Society by N[icholas] Trübner & Co., […], →OCLC, page 75:

Far more extravagant (insanior) yet is the idea of the whirling of the supposititious primum mobile, which is still higher, deeper, more immeasurable; and yet this incomprehensible primum mobile would have to be of matter, of enormous altitude, and far surpassing all the creation below in mass, for else it could not make the whole universe down to the earth revolve from east to west, and we should have to accept a universal force, an unending despotism, in the governance of the stars, and a hateful tyranny.

1893, William Gilbert, “Of the Daily Magnetic Revolution of the Globes, as against the Time-honored Opinion of a Primum Mobile: A Probable Hypothesis”, in P[aul] Fleury Mottelay, transl., William Gilbert of Colchester, Physician of London, on the Lodestone and Magnetic Bodies, and on the Great Magnet the Earth: A New Physiology, Demonstrated with Many Arguments and Experiments. [...] A Translation, New York, N.Y.: John Wiley & Sons, […], →OCLC, pages 320–321:

(astronomy, historical) The outermost celestial sphere of the heavens in Ptolemaic astronomy, which was believed to cause all the inner spheres to rotate.


intershell

"In this inner portion of the intershell 13C and N are totally absent, but there is some 16O."

1981, A. Renzini, “Evolutionary Effects of Mass Loss in Low-Mass Stars”, in Effects of Mass Loss on Stellar Evolution, →ISBN, page 332:

(astronomy) The layer between two stellar shells, particularly between the hydrogen and helium shells.


rille

(planetology) A long, narrow depression that resembles a channel, found on the surface of various lunar and planetary bodies.


standard ruler

(astronomy) Any astronomical object of known diameter whose distance can then be calculated from the angle it subtends


ISM

interstellar medium
interstellar medium#English

(astronomy) Abbreviation of interstellar medium.


radargram

/ˈɹeɪdɑɹɡɹæm/

(planetology, geology) A radar image of mineral deposits or a planetary surface.


SMC

Small Magellanic Cloud
w:Small Magellanic Cloud

(astronomy) Initialism of Small Magellanic Cloud.


LMC

Large Magellanic Cloud
w:Large Magellanic Cloud

(astronomy) Initialism of Large Magellanic Cloud.


precovery

LL-Q1860 (eng)-Flame, not lame-precovery.wav

If you look for your new object after discovery, it's called "recovery". [...] if you find your new object in some old data that someone took before you discovered your object, it's called a "precovery".

Quaoar [...] is a Trans-Neptunian object orbiting the Sun in the Kuiper belt. It was discovered on June 4, 2002 by astronomers Chad Trujillo and Michael Brown at the California Institute of Technology [...] The earliest precovery turned out to be a May 25, 1954 plate from Palomar Observatory.

(astronomy) The use of previously gathered data (especially photographic images) to recover a recently discovered object (typically a small solar system body).


twotino

This provides a possible explanation for the low fraction of twotinos compared to plutinos in the Kuiper belt.

2009, A. C. Quillen, “Resonances in Galactic and Circumstellar Disks”, in G. Contopoulos, P. A. Patsis, editors, Chaos in Astronomy: Conference 2007, Springer, page 199:

Plutinos are Kuiper belt objects in a 2:3 resonance (a = 39.4 AU) with Neptune and are named after Pluto since these bodies have orbits similar to Pluto. Twotinos are objects that are in a 1:2 resonance (a = 47.8 AU) with Neptune.

2017, Thomas H. Burbine, Asteroids, Cambridge University Press, page 234:

These objects have been given the name of twotinos (rhymes with "plutinos").
Interestingly, there are very few low-eccentricity TNOs beyond the twotinos.

2021, Barbara Ryden, Bradley M. Peterson, Foundations of Astrophysics, Cambridge University Press, page 276:

(astronomy) Any astronomical object, on the apparent outer edge of the Kuiper Belt, whose orbit has a 1:2 resonance with the planet Neptune.

Resonant trans-Neptunian object#1:2 resonance ("twotinos", period ~330 years)


submillimeter wave radiation

en-noun

submillimeter wave radiation (uncountable)

(astronomy) Electromagnetic waves with a wavelength less than one millimeter (the band begins at about 0.3 THz). A term often used by radio astronomers.


pericenter

(astronomy) The point of closest approach of an astronomical object in an elliptical orbit to its center of attraction.


HCO

Harvard College Observatory
w:Harvard College Observatory

(astronomy) Initialism of Harvard College Observatory.


superchondritic

LL-Q1860 (eng)-Flame, not lame-superchondritic.wav

(planetology, of an elemental ratio) Greater than found in a typical chondrite.


chondritic

en-adj

chondritic (comparative more chondritic, superlative most chondritic)

more chondritic (comparative)
most chondritic (superlative)

(planetology, of an elemental ratio) Similar to that found in chondrites.


facula

Borrowed from Latin facula (“little torch”).

Glaucous, hoar, enfouldered, cyathiform, / Making mere faculae of the sun and moon […]

c. 1933-1934, Hugh MacDiarmid, On a Raised Beach:

(astronomy) A bright spot or patch between sunspots.


inner planet

(astronomy, planets) Any planet of the Solar System whose orbit is located between the asteroid belt and the sun, i.e., any of Mercury, Venus, Earth, or Mars.

siseplaneet

planet of the Solar System with an orbit between the asteroid belt and sun


outer planet

(astronomy) Any planet of the Solar System whose orbit is located beyond the asteroid belt, i.e., any of Jupiter, Saturn, Uranus, or Neptune.

välisplaneet

planet of the Solar System with an orbit beyond the asteroid belt


minor planet

major planet

synonymous with planet in the 2006 IAU definition

(astronomy) An astronomical object in direct orbit around the Sun that is not a planet or a comet.


Beatrix

A Latinate variant of the standard English Beatrice.

(astronomy) 83 Beatrix, a main belt asteroid; named Beatrice Portinari, the beloved of Dante Alighieri.


libration

en-noun

libration (countable and uncountable, plural librations)

From Latin lībrātiō (“a hurling, swinging”), from lībrō (“poise, cause to swing”).

(astronomy) The apparent wobble or variation in the visible side of the Moon that permanently faces the Earth, allowing observers on Earth to see, over a period of time, slightly more than half of the lunar surface.


irregular galaxy

irregular galaxy (plural irregular galaxies)

The Magellanic Clouds are irregular galaxies.

(astronomy) A galaxy which is has no spirals and is not elliptical.

مَجَرَة غَيْر مُنْتَظِمَة

galaxy which has no spiral and is not elliptical


periodic comet

The computation of the elements of its orbit reveals the fact that they are almost identical with those of Comet III, 1869, and hence it becomes what in astronomical language is called a periodic comet.

1880, Lewis Swift, “The New Periodic Comet”, in Science, volume 1, number 21, page 258:

Comet Temple-Tuttle is what astronomers call a "periodic comet," one of hundreds that routinely and predictably continue to orbit the Sun.

2001 November 8, P. Clay Sherrod, Gian Trotta, “A History of the Leonid Storm”, in SPACE.com, retrieved 2016-01-26:

(astronomy) A comet which orbits the Sun and which returns to the innermost point of its orbit at known, regular intervals.


infalling

(astronomy) Moving towards a massive astronomical body under the influence of gravity


green flash

Frank T. Davies, physicist on board the City of New York, en route to the Antarctic regions with Byrd Antarctic Expedition, reports as follows on a green flash observed off Bermuda on the evening of August 29, 1928.

1929, J. A. Fleming, "Observations of Green Flash," Science, New Series, vol. 69, no. 1785, p. 298

(meteorology, astronomy) A rare phenomenon observed in morning or evening when the sun is crossing or immediately below the horizon, in which a momentary flash or ray of green light appears above the upper rim of the solar disk, caused by refraction of light in the atmosphere.


apastron

LL-Q1860 (eng)-I learned some phrases-apastron.wav

From English apo- (prefix meaning ‘away from, separate’) + Ancient Greek ᾰ̓́στρον (ắstron, “fixed star”), modelled after aphelion. Ἄ̆στρον (Á̆stron) is derived from ᾰ̓στήρ (ăstḗr, “celestial body (including a star, planet, meteor, etc.)”) (ultimately from Proto-Indo-European *h₂eHs- (“to burn; to glow”)) + -ον (-on, suffix forming nominative, accusative and vocative singular nouns).

der

(astronomy) The point of greatest separation between a celestial object and the star which it orbits.


Bayer system

(astronomy) A method of stellar classification in which stars are assigned Greek letters (α, β, γ, etc.) in decreasing order of brightness.


black drop effect

en-noun

black drop effect (plural black drop effects)

(astronomy) An optical effect, occurring during the transit of an object in front of the Sun, by which light is bent around the object, causing it to look stretched out.


blue flash

(meteorology, astronomy) A very rare phenomenon observed in the morning or evening when the sun is crossing or immediately below the horizon, in which a momentary flash of blue light appears above the upper rim of the solar disk, caused by refraction of light in the atmosphere.


Great Wall

Great Wall (disambiguation)#Astronomy
Great Wall of China

BOSS Great Wall

(astronomy) One of several galaxy filaments, which are the largest cosmic structures, being larger than a supercluster, forming partitions between cosmic voids, and contributing to the structure of the cosmic web.


orbital plane

The plane of ecliptic is the orbital plane of the earth and the other planets in the solar system.

(astronomy) The surface (plane) that contains an orbit.


plane of ecliptic

plane of ecliptic (plural planes of ecliptic)

(astronomy) The surface (plane) that contains the orbit of a planet in a solar system.


Dark Ages

/ˈdɑːˌkeɪd͡ʒɪz/

The phrase appears in writing of the English Reformation by Richard Sibbes (1620) and by George Abbot (1624), the archbishop of Canterbury. Both authors use it to refer to the period of papal supremacy before the Reformation. The earliest citation in Oxford English Dictionary is dated 1687. Use is specific to English therefore not likely to be from Latin.

(astronomy) The Dark Ages, 380 thousand to about 1 billion years after the Big Bang.


Dorian

en-adj

Dorian (comparative more Dorian, superlative most Dorian)

more Dorian (comparative)
most Dorian (superlative)

Constructed like the French Doriens. From the Latin root of Dōres + -ian. Compare Ancient Greek Δωριεύς (Dōrieús, “of Doris”).

cog

(astronomy) Of or relating to the asteroid (48) Doris.


Georgium Sidus

Coined by German-born British astronomer and composer William Herschel in 1781, after King George III + Latin sīdus (“star”).

coin

I cannot but wish to take this opportunity of expressing my sense of gratitude, by giving the name Georgium Sidus […] to a star, which (with respect to us) first began to shine under His auspicious reign.

1783, William Herschel, Philosophical transactions of the Royal Society of London, section 73.2:

The exclusion from the courts of the malign influence of all authorities after the Georgium sidus became ascendant, would uncanonize Blackstone.

The satellites of the Georgium Sidus, too, appear to move nearly at right angles to the plane of his orbit […]

1821, James Ferguson, Astronomy, volume II, page 86:

(astronomy, obsolete) The planet Uranus.


Herschel

(Uranus): after its discoverer, William Herschel.

(astronomy, obsolete) The planet Uranus. In use until the mid-19th century as an alternative to Georgium Sidus after King George III.

(astronomy) One of several impact craters in the Solar System, such as the one on Mimas.


lenticular galaxy

en-noun

lenticular galaxy (plural lenticular galaxies)

(astronomy) A galaxy that, like spiral galaxies, has a flat galactic disc, but which has lost most of its interstellar matter and therefore has no spirals; considered a transitional form between spirals and elliptical galaxies.

透鏡狀星系 /透镜状星系

galaxy that has flat disk but has lost most of its interstellar matter


asteroid belt

(astronomy) The main asteroid belt, the region of the orbital plane of the Solar System located between the orbits of Mars and Jupiter which is occupied by numerous minor planets (asteroids) and the dwarf planet Ceres.


asteroid belt

(astronomy) A set of orbits in a region that contains asteroids or similar minor planets arrayed as an annulus around the planetary system's orbital center.


radiosphere

(astronomy) The expanding sphere of radiation around a supernova


metallicity

(astronomy) The abundance of elements heavier than helium in stars as a result of nucleosynthesis.


nuller

(astronomy) An optical device that uses destructive interference to cancel out a strong light source, such as a star.


baryogenesis

(cosmology) The generation of baryonic matter in the early moments of the Big Bang.


astrophotography

As in most nature photography, the 35mm single lens reflex camera is probably the best choice for astrophotography.

1967, H. Charles Laun, The Natural History Guide, Alsace Books and Films, page 44:

Their^([CMOS sensors']) pixel size, linearity and noise performance are not necessarily ideal for astrophotography.

2017, Chris Woodhouse, The Astrophotography Manual, 2nd edition, Taylor & Francis (Routledge), page 10:

Astrophotography is a craft requiring development of skill, not just good equipment.

2018, Michael A. Covington, Digital SLR Astrophotography, 2nd edition, Cambridge University Press, page 18:

(astronomy, photography) The photography or imaging of astronomical objects, celestial events or areas of the night sky.


Galilean satellites

(astronomy) The four Galilean moons of Jupiter.


lunar occultation

lunar occultation (plural lunar occultations)

(astronomy) The passage of the Moon, as it moves through the nighttime sky, in front of a celestial object, such as a star or planet.


astrophoto

Once captured on film, an astrophoto does no good unless transferred to a form you can see and examine closely.

1973, Richard Berry, “Getting More Out of Your Astrophotos”, in Journal of the Royal Astronomical Society of Canada Newsletter, volume 67, page L32:

(astronomy, photography) An image of one or more celestial objects made using techniques of astrophotography.


celestial object

celestial object (plural celestial objects)

It is only 100 feet across but it now has the honor of being the solar system's fastest-spinning celestial object.

1999 July 22, “Asteroid Is Called Fastest-Spinning Solar System Object”, in space.com, retrieved 2009-01-09:

A symbol for each desired celestial object, such as for each planet, the sun, and the moon are included along with a method for detachably attaching each of the symbols to the zodiac chart.

2000, John Raymond Winks Jr., "Natal zodiac chart," US Patent 6,015,295, abstract

(astronomy, astrology) Synonym of celestial body.


superinflation

LL-Q1860 (eng)-Flame, not lame-superinflation.wav

(cosmology) A proposed inflation of spacetime in the early universe driven by the kinetic energy of the dilaton


intrinsic brightness

intrinsic brightness (plural intrinsic brightnesses)

Coordinate term: apparent brightness

(astronomy) The brightness that a star would have if not attenuated by distance or intervening gas or dust.


apparent brightness

apparent brightness (countable and uncountable, plural apparent brightnesses)

Coordinate term: intrinsic brightness

(astronomy) The brightness of a star as measured by an observer.


pyrheliometry

(astronomy) The study (and measurement) of solar radiation using a pyrheliometer.


preatmospheric

(astronomy) Describing a meteoroid as it approaches the atmosphere


achondrite

The study confirms a 20-year-old theory that balsaltic^([sic]) achondrite meteorites are projected off the surface of the asteroid 4 Vesta, the second largest asteroid in the solar system, which lies between Jupiter and Mars.

1993 April 27, “SCIENCE WATCH; New Light Is Shed On Moon's Brightness”, in The New York Times:

The Vestan, Lunar, and Martian meteorites are achondrites.

2011, Dieter Rehder, Chemistry in Space:

(astronomy, geology) Any stony meteorite that contains no chondrules.


circumstellar

(astronomy) That surrounds, or revolves around a star

околозвёздный

that surrounds, or revolves around a star


Julian year

(astronomy) A unit of measurement of time defined as exactly 365.25 days of 86400 SI seconds each.


astrograph

(astronomy) A telescope designed and used for astronomical photography.

astrograf

telescope used for astronomical photography


GW

gravitational wave
gravitational wave#English

(astronomy, astrophysics, physics) Initialism of gravitational wave.


LS

Local Supercluster
Local Supercluster#English

(astronomy) Initialism of Local Supercluster.


LY

LY (countable and uncountable, plural LYs)

(astronomy, countable) Alternative spelling of ly; light-year


Hidalgo

en-proper noun

Hidalgo (countable and uncountable, plural Hidalgos)

Borrowed from Spanish Hidalgo, from Spanish hidalgo, from Old Spanish fijo d'algo (“son of something”). The Mexican state is named after independence leader Miguel Hidalgo y Costilla.


alternative universe

en-noun

alternative universe (plural alternative universes)

In particular, it has been argued that if any of six (or perhaps a few more) numbers did not have rather particular values, then life as we know it would not be possible; atoms would not exist, or no grativationally bound structures would form in the Universe, or some other calamity would occur that would appear to make the alternative universe a very dull and lifeless place. How, then, did we get so lucky as to be here?

2007 June 21, Bernard Carr, editor, Universe Or Multiverse?, page 367:

(physics, cosmology) A hypothetical world situated in a different dimension of space and time than the real world consisting of the universe known and experienced by human beings.


gegenschein

gegenschein (countable and uncountable, plural gegenscheins)

/ˈɡeɪ.ɡənˌʃaɪn/

Borrowed from German Gegenschein (“counter-shine”), from gegen- + Schein.

bor+

My object in appearing before the Association, at this time, is to present the observations of several other persons on the gegenschein or completed arch of the zodiacal light, of which I have received accounts since our meeting in Motreal.

1860, George Jones, “Recent Observations, by various persons, on the Gegenschein, or Completed Arch of the Zodiacal Light”, in Proceedings of the American Association for the Advancement of Science, Volume 13, Digitized edition, published 2007, page 172:

The zodiacal light, gegenschein, and zodiacal band … are all visible.

2001 Feb, John E. Bortle, “Introducing the Bortle Dark-sky Scale”, in Sky and Telescope, volume 101, number 2, page 126:

(astronomy) A faint brightening of the night sky in the region of the ecliptic directly opposite the Sun.


spiral galaxy

(astronomy) A galaxy consisting of a number of arms of younger stars that spiral out from the center containing older ones.


LX

(astronomy) total X-ray luminosity of X-ray sources within the defined population


bolometric correction

en-noun

bolometric correction (plural bolometric corrections)

bolometric magnitude
bolometric magnitude

(astronomy) The difference between the bolometric magnitude and visual magnitude of a star


astrophotographer

(astronomy, photography) A person, especially an astronomer, who takes photographs of the stars


light echo

light echo (plural light echos or light echoes)

light echos (plural)
light echoes (plural)

(astronomy) A phenomenon caused by light reflected off surfaces distant from the source, and arriving at the observer with a delay relative to this distance, analogous to an echo of sound.


apoherm

periherm

antonym(s) of “a point in an orbit around the planet Mercury”

From Ancient Greek ἀπό (apó, “away”) + Ἑρμῆς (Hermês, “Hermes/Mercury, messenger of the gods”).

(astronomy) In an orbit around the planet Mercury, the point that is most distant from Mercury.


periherm

(astronomy) In an orbit around the planet Mercury, the point that is closest to Mercury.


cryovolcano

cryovolcano (plural cryovolcanoes or cryovolcanos)

cryovolcanoes (plural)
cryovolcanos (plural)

(planetology, geology, volcanology) A volcano on an icy moon that ejects volatile materials rather than magma.


Chandrasekhar limit

(astronomy) The maximum theoretical mass of a white dwarf, approximately 1.4 solar masses.

Chandrasekhar limit
Subrahmanyan Chandrasekhar


planetary nebula

planetary nebula (plural planetary nebulas or planetary nebulae)

planetary nebulas (plural)
planetary nebulae (plural)

Coined by William Herschel because of their apparent resemblance to the planet Uranus.

(astronomy) A nebulosity surrounding a dying red giant, consisting of material expelled by the star.


reflection nebula

reflection nebula (plural reflection nebulas or reflection nebulae)

reflection nebulas (plural)
reflection nebulae (plural)

The Pleiades are surrounded by a reflection nebula.

The Citadel is surrounded by a blue-tinted reflection nebula. The light of the nebula is actually light from the Citadel, scattered and reflected back at the station.

2008, BioWare, Mass Effect, Redwood City: Electronic Arts, →ISBN, →OCLC, PC, scene: Citadel Station: Serpent Nebula Codex entry:

(astronomy) A nebula that consists of dust which reflects starlight and appears blue in photographs.


supernova remnant

supernova remnant (plural supernova remnants)

The Crab Nebula is the most studied supernova remnant.

(astronomy) A nebula that is formed from supernova explosion debris.


Large Magellanic Cloud

(astronomy) A particular dwarf irregular galaxy, the largest satellite of Milky Way.


Small Magellanic Cloud

(astronomy) A particular dwarf irregular galaxy, a satellite of Milky Way.


dark nebula

dark nebula (plural dark nebulas or dark nebulae)

dark nebulas (plural)
dark nebulae (plural)

The Horsehead Nebula is a typical dark nebula, and is famous for resembling the head of a horse.

(astronomy) A type of nebula that does not emit or reflect (visible) light, and thus obscures light sources behind it.


apocenter

(astronomy) The furthest point of an astronomical object in an elliptical orbit to its center of attraction (the principal focus of the ellipse)

aposentri

the point in an orbit furthest from the center of attraction


polar cap

Earth's polar caps may melt if global warming continues.

The southern polar cap of Mars consists of both carbon dioxide and water ice.

(planetology) A high-latitude region of a celestial body that is covered by ice.


uranography

uranography (countable and uncountable, plural uranographies)

From Ancient Greek οὐρανογραφία (ouranographía).

uder

οὐρανογραφία

(astronomy, cartography) Celestial cartography; the mapping of celestial bodies.


visual binary

(astronomy) A binary star whose components can be visually resolved.


optical double

(astronomy) A star that appears as a double due to an optical illusion; in reality, the stars may be far apart from each other.


eclipsing binary

en-noun

eclipsing binary (plural eclipsing binaries)

(astronomy) Any of a class of extrinsic variable stars where changes in brightness are caused by stars eclipsing each other.


giant star

(astronomy) A star that has stopped fusing hydrogen in its core and as a result has grown much larger and brighter.


dwarf star

→ Irish: abhacréalta (calque)

From dwarf + star. Compare West Frisian dwerchster (“dwarf star”), Dutch dwergster (“dwarf star”), German Zwergstern (“dwarf star”), Danish dværgstjerne (“dwarf star”), Swedish dvärgstjärna (“dwarf star”), Icelandic dvergstjarna (“dwarf star”).

(astronomy) A star that is located in the main sequence in the Hertzsprung-Russell diagram, though generally excluding the small minority which fall in the blue band due to their large size and high luminosity; fuses hydrogen into helium in its core.

نَجْم قَزَم

star that is a located in the main sequence


radio source

Some quasars are bright radio sources.

(astronomy) Any astronomical object that emits radio waves.

radiosource

any astronomical object that emits radio waves


tholin

→ French: tholin

French: tholine

From Ancient Greek θολός (tholós, “muddy”) + -in. Coined by Carl Sagan and Bishun Khare in 1979. From the muddy coloration that this class of chemical compounds appear to have, when observed on the Saturnian moon Titan, and from Miller–Urey-style experiments.

suffix

(organic chemistry, astronomy) Any of several poorly classified heteropolymers derived from simple hydrocarbons and ammonia formed by solar irradiation in the atmospheres of icy planets and moons.


gamma-ray burst

en-noun

gamma-ray burst (plural gamma-ray bursts)

(astronomy) A flash of gamma rays that seem to originate from a random point in the sky; their most likely sources are believed to be supernova explosions of a very massive stars and mergers of neutron stars.


Gl

(astronomy) the prefix of catalog entries in the Gliese star catalog, for initial catalog

(astronomy) by extension, prefix for any catalogued in the Gliese star catalog and expansions


microlensing

gravitational lensing
gravitational lensing


gravitational lensing

(astronomy) The action of a highly-massive object (such as a star, galaxy, or black hole) that acts as a gravitational lens and focuses light from a light source (such as another star or galaxy) that passes behind it as observed from the Earth.


Pandora

Borrowed from Ancient Greek Πανδώρᾱ (Pandṓrā, “all gifts”).

bor

(astronomy) A moon of the planet Saturn.

(astronomy) 55 Pandora, a main belt asteroid.


anomalistic

en-adj

anomalistic (comparative more anomalistic, superlative most anomalistic)

more anomalistic (comparative)
most anomalistic (superlative)

(astronomy) Of or pertaining to an anomaly (angle of a body from its perihelion)


diamond ring

(astronomy) An optical phenomenon visible during a moment of a solar eclipse when only a tiny part of the sun is not obscured by the moon, shining like a diamond in the ring of the sun’s corona.

鑽石環 /钻石环

optical phenomenon during a solar eclipse


Eugenia

From Ancient Greek Εὐγενία (Eugenía), feminine form of Εὐγένιος (Eugénios) ( =Eugene) "well born".

(astronomy) 45 Eugenia, a main belt asteroid.


nebulosity

en-noun

nebulosity (countable and uncountable, plural nebulosities)

With higher powers the field does not appear to be sufficiently large to allow of each streak of nebulosity being compared with the surrounding parts where the nebulosity is not quite so bright.

1868, Lord Oxmantown, An account of the observations on the great nebula in Orion:

If one conceives by analogy all the stars formed in this manner, one can imagine their anterior state of nebulosity itself preceded by other stars in which the nebulous matter was more and more diffuse, the nucleus being less and less luminous and dense.

2007, Stephen Hawking, God Created The Integers: The Mathematical Breakthroughs that Changed History:

(meteorology, astronomy) The characteristic of being nebulous; cloudiness (measured in octas).


GJ

(astronomy) GJ the prefix of catalog entries in the Gliese star catalog, for the Gliese-Jahreiss expansion

(astronomy) by extension, prefix for any catalogued in the Gliese star catalog


Rhean

en-adj

Rhean (comparative more Rhean, superlative most Rhean)

more Rhean (comparative)
most Rhean (superlative)

1978, American Geophysical Union, Lunar and Planetary Institute, Proceedings of the Lunar and Planetary Science Conference, University of Michigan,
The central peaks of Rhean craters appear to be larger with respect to crater size than for lunar and Mercurian craters.

(astronomy) Of or relating to the Saturnian moon named for Rhea.


Titanian

if Trafton's (1972) detection of Titanian H₂ is correct, ...

1974, McDonough & Brice, "The Saturnian 'Gas-Doughnut' Hypothesis", in A. Woszczyk, ed., Exploration of the Planetary System, p 484

The Titanian atmosphere consists predominantly of nitrogen gas, with only a few percent methane, the simplest organic molecule.

2006, Kevin W. Plaxco, Michael Gross, Astrobiology: A Brief Introduction, Johns Hopkins University Press, page 238:

(astronomy) Of Titan, the largest moon of Saturn.

an isolated colony of Uranus' moon Titania, one of the diminishing vestiges of the Titanian Empire

1985, Piers Anthony, Bio of a Space Tyrant, vol. 3: Politician:

(astronomy) Of Titania, the largest moon of Uranus.


Callistoan

(astronomy) Of or pertaining to Callisto, the second largest moon of Jupiter, named for the nymph Callisto.


Europan

indications of Europan biology

The specifics of how an ocean and the Europan surface might interact, however, are far from agreed-upon.

2004, Pascale Ehrenfreund, “Mars, Europa, and Beyond”, in Astrobiology: Future Perspectives, Kluwer Academic Publishers, page 437:

(astronomy) Pertaining to Europa, a moon of Jupiter named for the mythological figure, or any theoretical or fictional inhabitants of the moon Europa.

(astronomy) Pertaining to (52) Europa, a minor planet in the Main Asteroid Belt.


Gly

(astronomy) Abbreviation of gigalightyear.; a unit of a billion lightyears


Methone

From Latin Methōnē, from Ancient Greek Μεθώνη (Methṓnē). Doublet of Methoni and Modon.

(astronomy) A small satellite of Saturn.


Eurydice

From Latin Eurydicē, from Ancient Greek Εὐρυδίκη (Eurudíkē).

(astronomy) 75 Eurydike, a main belt asteroid.


Euphrosyne

Translingual: Euphrosyne

From Ancient Greek Εὐφροσύνη (Euphrosúnē).

(astronomy) 31 Euphrosyne, a main belt asteroid.


Canicula

From Latin Canīcula (“Sirius; Canis Major”), from canīcula (“puppy”), from canis (“dog”) + -ula (diminutive suffix).

(historical astronomy) Synonym of Sirius, particularly in Latin contexts.


albedo feature

(planetology) On a Solar System body, a region with distinct brightness when seen using a telescope; often does not correspond any real geological formation.


Tritonian

(astronomy) Of or pertaining to the largest moon of Neptune, named after Triton.


island universe

en-noun

island universe (plural island universes)

Many stories have been invented to account for this milky band of light, but today we know that it is the light of millions and millions of stars making up our “Island Universe” the Milky-Way Galaxy.

1968 January 15, “Skies Over Port Huron”, in Port Huron Times Herald, volume 58, number 15, Port Huron, Mich., section A, page 8:

You will notice that the wide band of sky which follows the Milky-Way from the northeastern horizon to straight overhead (through the summer triangle mentioned in the Aug. 14 Nugget) and on to the southern horizon is far richer in stars than the rest of the sky. This is because the Milky-Way Galaxy, our local “island universe,” is a disk-shaped object and quite thin in comparison with its diameter.

1975 August 28, Stephen Dodson, “There’s a star in the sky for each person on earth”, in The North Bay Nugget, 69th year, number 62, North Bay, Ont., page 7:


Maunder minimum

Maunder minimum (plural Maunder minimums or Maunder minima)

Maunder minimums (plural)
Maunder minima (plural)

(astronomy) A period similar to the Maunder Minimum observed on a star other than the Sun.


Maunder Minimum

(astronomy, climatology) The period between 1645 and 1715 marked by records and other indications of very low levels of sunspot activity of the Sun, corresponding to a period of global cooling.


biaxial

(mathematics, astronomy) Having two axes of rotation and two planes of symmetry (e.g. having the shape of a spheroid)


astrochemistry

(chemistry, astronomy) The study of the chemical composition of stars and outer space

astroquímica

the study of the chemical composition of starts and outer space


astrochemist

(chemistry, astronomy) A chemist or astronomer whose speciality is astrochemistry.


star trail

The idea behind photographing star trails is wonderfully simple. Just take your old mechanical camera, point it skyward, and leave the shutter open.

2001, Eric DeBolt, “Happy Trails”, in Astronomy, volume 29, number 7, page 74:

(astronomy, photography) The line of light recorded on a photographic medium when a time exposure is made of a star in the nighttime sky using a camera on a fixed mount, caused by the rotation of the earth during the period of time when the camera's shutter is held open.


TLB

(astronomy, Milky Way) Initialism of The Local Bulb.


Menkalinan

Shortened form of Arabic مَنْكِب ذِي الْعِنَان (mankib ḏī l-ʕinān, “shoulder of the rein-holder”).

uder

مَنْكِب ذِي الْعِنَان

(astronomy) A traditional name of the star Beta Aurigae.


collapsar

Blend of collapse + star, patterned after quasar, pulsar. Analyzable as collapse + -ar

(astronomy) The black hole thought to form following the gravitational collapse of a massive star.


hypernova

en-noun

hypernova (plural hypernovas or hypernovae)

(astronomy) The gravitational collapse of a massive star to form a black hole.

hipernova

the gravitational collapse of a massive star to form a black hole


Kore

Learned borrowing from Ancient Greek κόρη (kórē, “girl, maiden”).


super-Earth

LL-Q1860 (eng)-Flame, not lame-super-Earth.wav

Coordinate term: sub-Earth

Researchers had been hoping to spot water vapor in the atmosphere of a more Earth-like planet, especially one in its star’s habitable zone, but these worlds are relatively small, making observations of their atmospheres extraordinarily difficult. The larger the planet, the easier the detection, so researchers focused their efforts on super-Earths: planets with masses up to 10 times that of our home planet, which means they might also sport rocky surfaces.

2019 September 11, Michael Greshko, “Water found on a potentially life-friendly alien planet”, in National Geographic:

(astronomy) Any extrasolar rocky planet several times larger than Earth, especially such a planet detected as it transits its star.

super-terre

extrasolar planet several times larger than Earth


plutoid

(astronomy, obsolete) A trans-Neptunian dwarf planet.


trinary

From Late Latin trīnārius (“consisting of three”), from Latin trīni (“triple, three each”) + -ārius.


QSR

quasi-stellar radio-source
quasi-stellar radio-source#English

(astronomy) Initialism of quasi-stellar radio-source.


QSS

quasi-stellar source
quasi-stellar radio-source#English

(astronomy, obsolete) Initialism of quasi-stellar source.


BSO

(astronomy, obsolete) Blue stellar object: a radio-quiet quasar.


QSG

(astronomy, obsolete) Quasi-Stellar Galaxy, a quasar


DRAGN

(astronomy) Acronym of double radio-source associated with a galactic nucleus.


radio halo

(astronomy) A diffuse region of material, surrounding a galaxy or a pulsar, that emits radio waves.


HzRG

(astronomy) Initialism of high-redshift radio galaxy.


LIRG

(astronomy) Acronym of luminous infra-red galaxy.


ULIRG

(astronomy) Acronym of ultra-luminous infra-red galaxy.


BLRG

(astronomy) broad emission-line radio-galaxy


NLRG

(astronomy) narrow emission-line radio-galaxy


NELG

(astronomy) Initialism of narrow emission-line galaxy.


ElG

elliptical galaxy
elliptical galaxy#English

(astronomy) Abbreviation of elliptical galaxy.


dSph

dwarf spheroidal galaxy
dwarf spheroidal galaxy#English

(astronomy) Abbreviation of dwarf spheroidal galaxy.


dI

dwarf irregular galaxy
dwarf irregular galaxy


DIG

dwarf irregular galaxy
dwarf irregular galaxy#English

(astronomy) Initialism of dwarf irregular galaxy.


dE

dwarf elliptical galaxy
dwarf elliptical galaxy


DEG

en-noun

DEG (countable and uncountable, plural DEGs)

dwarf elliptical galaxy
dwarf elliptical galaxy#English

(astronomy) Initialism of dwarf elliptical galaxy.


gE

giant elliptical galaxy
giant elliptical galaxy


(astronomy) narrow emission-line Seyfert type-1 galaxy


(astronomy) broad emission-line Seyfert type-1 galaxy


NLQ

narrow emission-line quasar
narrow emission-line quasar#English

(astronomy) Initialism of narrow emission-line quasar.


BLQ

(astronomy) Abbreviation of broad emission-line quasar.


RIQ

(astronomy, initialism) Radio-intermediate quasar.


RQQ

(radio astronomy) Initialism of RadioQuiet Quasar.


LQ

LQ (countable and uncountable, plural LQs)

lunar quadrangle
lunar quadrangle#English

(countable, selenography, astrocartography, astrogeography) Abbreviation of lunar quadrangle.


Makemake

(astronomy) A dwarf planet orbiting in the Kuiper belt, discovered in 2005.

Ceres

most likely dwarf planets of the Solar System


cycler

LL-Q1860 (eng)-Flame, not lame-cycler.wav

The Earth-Mars cyclers could potentially be used for transporting people between the two planets.

(astronomy) An orbit that approaches two astronomical bodies on a regular basis.


radio-bright

en-adj

radio-bright (comparative more radio-bright, superlative most radio-bright)

more radio-bright (comparative)
most radio-bright (superlative)

(astronomy) That emits significant amounts of radio waves; radio-luminous


radio-luminous

radio-luminous (comparative more radio-luminous, superlative most radio-luminous)

more radio-luminous (comparative)
most radio-luminous (superlative)

(astronomy) That emits significant amounts of radio waves; radio-bright.


radio burst

(astronomy) A brief emission of intense radio waves from a star etc.


TNO

trans-Neptunian object
trans-Neptunian object#English

(astronomy) Initialism of trans-Neptunian object.


SDO

en-noun

SDO (countable and uncountable, plural SDOs)

(astronomy) Initialism of scattered-disc object.


microquasar

(astronomy, stars) A high-energy binary star system that includes black hole or neutron star and which resembles a quasar.


ORC

ORC (countable and uncountable, plural ORCs)

Even those who never look into the night sky and wonder about stars or galaxies may find the new research interesting, Diamond-Stanic said, because ORCs help to explain how the galaxy we live in came to be.

2024 January 12, Deirdre Stires, “Those odd circles in space? They’re now explained thanks to scientists including Aleks Diamond-Stanic”, in Bates News:

(astronomy) Acronym of odd radio circle, a very large unexplained astronomical object.


supergranule

LL-Q1860 (eng)-Flame, not lame-supergranule.wav

supergranulation cell
supergranulation cell


supergranulation cell

supergranulation cell (plural supergranulation cells)

(astronomy) A large region of convection in the photosphere of the sun; a supergranule


tachocline

From tacho- + -cline; coined in a paper by Edward A. Spiegel and Jean-Paul Zahn in 1992 (Spiegel, E. A.; & Zahn, J.-P.; "The solar tachocline", Astronomy and Astrophysics, 265, 106–114, 1992) by analogy to the oceanic thermocline.

(astronomy) A region of abrupt transition from rotation to convection in the interior of the sun.


curtate

en-adj

curtate (comparative more curtate, superlative most curtate)

more curtate (comparative)
most curtate (superlative)

Latin curtatus, past participle of curtare (“to shorten”).

(astronomy) said of the distance of a planet from the sun or earth, as measured in the plane of the ecliptic, or the distance from the sun or earth to that point where a perpendicular, let fall from the planet upon the plane of the ecliptic, meets the ecliptic


curtation

(astronomy) The interval of a planet's orbit in which its curtate or shortened distance is less than the true distance.


Octavia

From Latin Octāvia, feminine form of the gens name Octāvius, from octavus (“the eighth”).

(astronomy) 598 Octavia, a minor planet orbiting around the Sun.


Barlow

From Old English bere (“barley”) + hlǣw (“hill”) or lēah (“wood, clearing”).


sesquiquadrate

From sesqui- (“one and a half”) + quadrate (“right-angled”).

prefix

(astronomy) A sesquiquadrate aspect or position; an angle of 135°: (a square [90°] + a semisquare [45°]; abbrv. Ses).

puolitoistaneliö

astrology: 135° angle between celestial objects


galactic year

(astronomy) The time taken for the Solar System to orbit around the center of the Milky Way Galaxy, estimated to be from 225 to 250 million years.

(astronomy, by extension) The time taken for a celestial body to complete a quasi-orbit in a galaxy.


perilune

(astronomy) The point of an elliptical lunar orbit where the distance between the satellite and the Moon is at its minimum.

perilunium

point of lunar orbit that is closest to the Moon


elliptical galaxy

en-noun

elliptical galaxy (plural elliptical galaxies)

(astronomy) A type of galaxy with an approximately ellipsoidal shape and a smooth, nearly featureless image.

مَجَرَة إِهْلِيجِيَّة

galaxy having smooth, featureless light-profile


RRAT

rotating radio transient
rotating radio transient#English

(astronomy) Initialism of rotating radio transient: a type of pulsar


linea

From Latin līnea (“line, thread”), via Spanish línea in reference to the unit of length, from līnum (“flax”). Doublet of line.

The moons Dione and Europa have prominent lineae.

(astronomy, geology) Any long marking, dark or bright, on a planet or moon's surface.


lacertid

From the name of the first discovered example, BL Lacertae.

In the same diagram a compact galaxy, 3C 371, and a Seyfert, 3C 120, lie very close to the Lacertids.

1975 July 10, “Quasars and Lacertids show a family likeness”, in New Scientist, page 61:

These reliably variable objects included three ROCOSs (OE 400, OI 090.4, and PI034-293) and two lacertids (AO 0235+164 and OJ 287).

1990, Bulletin of the Special Astrophysical Observatory-North Caucasus, volumes 24-26, page 67:

We have identified six radio sources in the Zelenchuk (RATAN-600) catalog with two quasars, two lacertids, and two pairs of galaxies.

1993, Astronomy Reports, volume 37, American Institute of Physics, page 466:

active galactic nucleus
active galactic nucleus

(astronomy) A type of blazar (highly variable active galactic nucleus) that lacks spectral emission lines characteristic of quasars.


Callippic

For Callippus, Greek astronomer and mathematician

(astronomy) Based upon a common multiple of the year and the month


meteoriticist

The following is a not-too-imaginary conversation between a meteoriticist and an important on-the-spot witness to a fireball that went soaring over his alfalfa patch.

1967, Robert Shirley Richardson, Getting Acquainted with Comets, McGraw-Hill, page 133:

In spite of this reservation, most meteoriticists now accept extinct aluminum-26 as the most likely source of heat for the meteorite parent bodies: it was abundant when the solar system formed, and it decayed fast enough to account for the intense but brief thermal histories of most meteorites.

1986, Robert T. Dodd, Thunderstones and Shooting Stars: The Meaning of Meteorites, Harvard University Press, page 90:

Most of the meteoriticists who "discover" new meteorites depend on someone from the general public to bring in a strange rock they have encountered.

1997, The Planetary Report, volumes 17-18, The Planetary Society, page 20:

(astronomy, mineralogy, geochemistry, cosmochemistry) A scientist involved in meteoritics.


cosmical

en-adj

cosmical (comparative more cosmical, superlative most cosmical)

more cosmical (comparative)
most cosmical (superlative)

(astronomy, dated) Rising or setting with the sun; not acronycal.


Archimedes

är′kə-mēʹdēz

/ˌɑːɹkɪˈmiːdiːz/

Learned borrowing from Latin Archimēdēs, from Ancient Greek Ἀρχιμήδης (Arkhimḗdēs).

(astronomy) A large lunar impact crater on the eastern edges of the Mare Imbrium.


UDG

ultra diffuse galaxy
ultra diffuse galaxy#English

(astronomy) Initialism of ultra diffuse galaxy.


doomsday event

The universe will contract and grow hotter until the doomsday event that astronomers have dubbed "the big crunch."

1995 April 7, Malcolm W. Browne, “A Research Team Detects Many More Galaxies”, in New York Times, retrieved 2008-07-05:

In this subsection we face the question about the possibility of evading the doomsday event in phantom models of dark energy with interaction, which are inspired in scalar-tensor theories of gravity.

2006, Ruben Curbelo et al., “Interacting phantom energy and avoidance of the big rip singularity”, in Classical and Quantum Gravity, volume 23, number 5, page 1591:

Sceptics claim switching on the supercooled magnets could create a doomsday event that would destroy the Earth.

2008 July 2, “World to end in August (maybe)”, in New Zealand Herald, retrieved 2008-07-05:

(cosmology, astronomy) An occurrence which causes the end of the universe or which destroys the planet earth; a global cataclysm.


Leonids

(astronomy) The meteor shower that appears to originate from the constellation of Leo.


fixed star

Originally so named as to distinguish the stars that appear to have a fixed position on the firmament from the “wandering stars”, i.e., the planets.

(astronomy) A star whose movement cannot be seen from Earth.


magnetotail

(astronomy) The long, trailing part of a magnetosphere on the side of a planet furthest from the sun

magnetostaart

the long, trailing part of a magnetosphere


magnetosheath

(astronomy) The region of space between the magnetopause and the bow shock of a planet's magnetosphere


planetography

(astronomy) The branch of astronomy concerned with the description of the physical features of planets


SGR

The expected gamma-ray spectrum of the Soft Gamma-ray Repeater SGR 1900+14 for various inclination angles.

2004, K.S. Cheng, Gustavo E. Romero, editors, Cosmic Gamma-Ray Sources, figure caption, page 191:

Other missing neutron stars might be the unpredictable soft gamma-ray repeaters (SGRs), the recurrent soft X-ray transients discovered in the 1980s. Although there are only a few examples known at present, SGRs have attracted a lot of attention lately because of their unique characteristics.

2004, Quang Ho-Kim, Narendra Kumar Kumar, Harry C. S. Lam, Invitation to Contemporary Physics, 2nd edition, page 308:

2008, W. Becker, F, Haberl, J Trümper, 14: Pulsars and Isolated Neutron Stars, Joachim E. Trümper, Günther Hasinger (editors), The Universe in X-Rays, page 193,
The radio-silent neutron stars include anomalous X-ray pulsars (AXPs), soft gamma-ray repeaters (SGRs), and “quiescent” neutron star candidates in SNRs. There is growing evidence that AXPs and SGRs are indeed magnetars (see [109] for a review).

soft gamma-ray repeater
soft gamma-ray repeater#English

soft gamma repeater
soft gamma repeater#English

(astronomy) Initialism of soft gamma-ray repeater or soft gamma repeater.


AXP

The radio-silent neutron stars include anomalous X-ray pulsars (AXPs), soft gamma-ray repeaters (SGRs), and “quiescent” neutron star candidates in SNRs. There is growing evidence that AXPs and SGRs are indeed magnetars (see [109] for a review).

2008, Joachim E. Trümper, Günther Hasinger (editors), The Universe in X-Rays, page 193:

(astronomy) Initialism of anomalous X-ray pulsar.


dEG

(astronomy) Initialism of dwarf elliptical galaxy.


Irr

irregular galaxy
irregular galaxy#English

(astronomy) Abbreviation of irregular galaxy.


HVC

high velocity cloud
high velocity cloud#English

(astronomy) Initialism of high velocity cloud.


HVS

en-noun

HVS (countable and uncountable, plural HVSes)

hypervelocity star
hypervelocity star#English

(astronomy) Initialism of hypervelocity star.


LBV

luminous blue variable
w:luminous blue variable

(astronomy) Initialism of luminous blue variable.


triaxial

(mathematics, astronomy) Having three planes of symmetry (e.g. having the shape of a scalene ellipsoid) and thus two axes of rotation


coronagraphy

(astronomy) The viewing of near-sun or near-stellar objects using a coronagraph


exoplanetary

(astronomy) Of or pertaining to an exoplanet, a planet outside the solar system


substellar

a substellar companion

(astronomy, of an object) Having a mass less than the minimum necessary mass for hydrogen fusion


bolometric magnitude

bolometric magnitude (countable and uncountable, plural bolometric magnitudes)

(astronomy) The magnitude of a star in terms of the total amount of radiation received at all wavelengths


intracrater

an intracrater dune formation

(geomorphology, astronomy) Occurring within a crater


Cl*

(astronomy) a cluster of stars — a star cluster


ClG

(astronomy) Abbreviation of galaxy cluster.


Pele-type

(astronomy, geology) Describing an eruption or volcano similar to that of Pele on Io (the moon of Jupiter).


Prometheus-type

(astronomy, geology) Describing an eruption or volcano similar to those on Prometheus (the moon of Saturn).


rayleigh

(physics, astronomy) A unit of brightness (of the sky at night) equal to 10¹⁰/4π quanta per square meter per second per steradian


Kepler shear

From Johannes Kepler, German astronomer.

(astronomy) The effect of differential rotation speeds in the rings of Saturn


coplanarity

coplanarity (countable and uncountable, plural coplanarities)

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Gliese 876 affords us by far our most detailed and accurate map of any extrasolar planetary system in the solar neighborhood, and […] it is reassuring to see a kinship in the most fundamental property of system coplanarity.

2009 January 9, Robert Naeye, “Exoplanets' Dance Reveals They're Coplanar”, in skyandtelescope.com, retrieved 2009-01-09:

(astronomy, of multiple planets or other orbiting bodies) The state or characteristic of orbiting a central celestial object within the same orbital plane.


twilight zone

Because such a zone (in the literal sense of the term) is twilit; see twilight § Etymology.

Coordinate term: greyline

(astronomy, astrophysics) A moving line that divides the daylit side and the dark night side of a planetary body.


preplanetary nebula

preplanetary nebula (plural preplanetary nebulae or preplanetary nebulas)

preplanetary nebulae (plural)
preplanetary nebulas (plural)

(astronomy) A stage in stellar evolution when a star starts to shed its outer layers before coming a true planetary nebula.


protoplanetary nebula

protoplanetary nebula (plural protoplanetary nebulae or protoplanetary nebulas)

protoplanetary nebulae (plural)
protoplanetary nebulas (plural)


Alpha Centauri C

From Alpha Centauri. Astronomers believe that Proxima Centauri is gravitationally bound to the Alpha Centauri system.


Alpha Centauri A

(astronomy) The brightest star in the southern constellation of Centaurus. Alpha Centauri is actually a binary star with Alpha Centauri C or Proxima Centauri as a third component. Alpha Centauri A is the brightest star of the system and is somewhat brighter than our sun. Alpha Centauri B is somewhat fainter than Alpha Centauri A but much brighter than Proxima Centauri.


Alpha Centauri B

(astronomy) The brightest star in the southern constellation of Centaurus. Alpha Centauri is actually a binary star with Proxima Centauri as a third component. Alpha Centauri B is less bright than Alpha Centauri A and is somewhat less bright than our sun.


head

my very educated mother just served us nine pumpkins

From the initial letters of the names of the eight planets, plus Pluto, formerly considered a planet.

(astronomy, slightly dated, mnemonic) Used to remember the order and names of the (then) nine planets of the solar system: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto.

mein Vater erklärt mir jeden Sonntag unsere neun Planeten

my very educated mother just served us nine pizzas

my very educated mother just served us nachos

my very educated mother just served us noodles


Magellanic Clouds

Large Magellanic Cloud
Large Magellanic Cloud

Small Magellanic Cloud
Small Magellanic Cloud

(astronomy) Collectively, the pair of galaxies, the Large Magellanic Cloud and Small Magellanic Cloud; also sometimes includes the Magellanic Bridge and Magellanic Stream.


kiloparsec

(astronomy) A unit of distance equal to one thousand parsecs.


megamaser

(astronomy) Any celestial object exhibiting enormous maser activity


RD

en-noun

RD (countable and uncountable, plural RDs)


supercluster

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(astronomy) An extended group of clusters of galaxies

超星系團 /超星系团

astronomy: extended group of galaxy clusters


superplanet

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(astronomy, planetology) Any very large planet, but especially a large superjovian gas giant


MLE

MLE (countable and uncountable, plural MLEs)

(planetology, areology) Initialism of multi-layer ejecta.


Electra

From Ancient Greek Ἠλέκτρα (Ēléktra), from ἤλεκτρον (ḗlektron, “amber”), related to ἠλέκτωρ (ēléktōr, “shining sun”).

(astronomy) One of the stars in the Pleiades star cluster.


gyrochronology

(astronomy) A method of estimating the age of a star by measuring its rotation rate


armill

From Middle French armille, from Latin armilla (“bracelet”). Doublet of armilla.

The Armill, Astrolabe, Dioptra, and Parallactic Instrument of the ancients were some of the instruments thus constructed.

1840, William Whewell, “Introduction”, in The Philosophy of the Inductive Sciences, Founded upon Their History. […], volume II, London: John W[illiam] Parker, […]; Cambridge, Cambridgeshire: J. and J. J. Deighton, →OCLC, part II (Of Knowledge), book XIII (Of Methods Employed in the Formation of Science), paragraph 5, page 489:

This instrument was called an equinoctial armil. Observations taken in this manner must necessarily be very inaccurate, owing to the refraction.

1856, Hannah M. Bouvier, Familiar Astronomy, or an Introduction to the Study of the Heavens, page 328:

The instruments at this observatory were much admired and included an armillary sphere, a mural quadrant and a solstitial armil.

1970, Philip Khuri Hitti, History of the Arabs, 10th edition, →ISBN, page 378:

(historical, astronomy) An ancient astronomical instrument, having either one ring placed in the plane of the equator for determining the time of the equinoxes (an equinoctial armil) or two or more rings, one in the plane of the meridian, for observing the solstices (a solstitial armil).

armil·la

ancient astronomical instrument — see also armillary sphere


farside

(astronomy) The side of a moon that faces away from the planet that it orbits.


pericentric

en-adj

pericentric (comparative more pericentric, superlative most pericentric)

more pericentric (comparative)
most pericentric (superlative)

(astronomy) Of or pertaining to a pericentre


planethood

Late 17th century; earliest use found in Nathaniel Fairfax (1637–1690), physician and antiquary. Constructed as planet + -hood

(astronomy) The state or condition of being a planet.


prograde

prograde (comparative more prograde, superlative most prograde)

more prograde (comparative)
most prograde (superlative)

/ˈpɹəʊɡɹeɪd/

/ˈpɹoʊɡɹeɪd/

From pro- (“forward”) + -grade (“direction”).

(astronomy) Moving in a forward direction, especially with respect to other bodies in the same system.

prográdní

(astronomy) moving in a forward direction


major planet

minor planet

smaller than Earth (in the Solar System)

dwarf planet

antonym(s) of “2006 IAU definition of planet”

a planet that does not fit the 2006 IAU definition of planet (i.e. Pluto)

(astronomy) Any of the 8 celestial bodies which orbit the Sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune (a celestial body that fits the 2006 IAU definition of planet).

(astronomy) Any planet that is significantly larger and more massive than Earth, containing large amounts of hydrogen and helium, such as Jupiter and Neptune.


heliophysics

(physics, astronomy) The physics of the Sun and its interactions with objects within the heliosphere


twin quasar

gravitational lensing
gravitational lensing

(astronomy) a pair of quasar images formed by gravitational lensing of a single physical quasar


double quasar

(astronomy) Two quasars that form a system, such that they gravitationally interact, or are part of the same cluster of galaxies; a binary quasar.

(astronomy) Two quasars that appear to be paired when seen in an image, either because they orbit one another (binary quasars) or happen to be in the same line of sight even though they are separated by a great distance.


finderscope

(astronomy) A small telescope, or other sighting device, mounted on top of a main telescope to enable approximate directional positioning.


solar-type

(astronomy, of a star) Having similar characteristics to those of the Sun.


trinary star

(astronomy) A stellar system that has three stars orbiting around each other; triple star.


triple star

(astronomy) Three stars which form a stellar system, such that they orbit the point of equilibrium of their gravitational fields; a trinary star.

(astronomy) Three stars that appear to be one when seen with the naked eye, either because they orbit one another (trinary stars) or happen to be in the same line of sight even though they are separated by a great distance.


quadruple star

quadruple star system
quadruple star system

(astronomy) Four stars which form a stellar system, such that they orbit the point of equilibrium of their gravitational fields; a quadruple star system.

(astronomy) Four stars that appear to be one when seen with the naked eye, either because they orbit one another (quadruple star systems) or happen to be in the same line of sight even though they are separated by a great distance.


quadruple star system

en-noun

quadruple star system (plural quadruple star systems)

(astronomy) A stellar system that has four stars orbiting around each other; quadruple star


multiple star

multiple star system
multiple star system

(astronomy) Multiple stars which form a stellar system, such that they orbit the point of equilibrium of their gravitational fields; a multiple star system.

(astronomy) Multiple stars that appear to be one when seen with the naked eye, either because they orbit one another (multiple star systems) or happen to be in the same line of sight even though they are separated by a great distance.


multiple star system

multiple star system (plural multiple star systems)

(astronomy) A stellar system that has multiple stars orbiting around each other; multiple star


binary star system

binary star system (plural binary star systems)


trinary star system

trinary star system (plural trinary star systems)


double star system

double star system (plural double star systems)


triple star system

triple star system (plural triple star systems)


single star system

single star system (plural single star systems)

(astronomy) A star system consisting of a solitary star not gravitationally bound to other stars


double planet

(astronomy) A planet with a moon large enough to be considered a planet, were the planet not there, having a substantial portion of the system's overall mass.

(astronomy) A pair of planemos in orbit around each other, where the barycenter of their orbits lies outside of both planemos, which in turn is in orbit about a star.

(astronomy) A pair of planemos in orbit around each other, where the barycenter of their orbits lies outside of both planemos.

(astronomy) A planemo with a moon large enough to be considered a planemo, having a substantial portion of the system's overall mass.


planemo

Contraction of planetary-mass object. Coined by Gibor Basri, Professor of Astronomy at the University of California, Berkeley, (UCB) at the 2003 IAU conference.

Other groups have also recently identified young, isolated planemos; understanding how such isolated, ultra-low masses form presents a challenge.

2003 December 1, Jacques Lépine, Jane Gregorio-Hetem, Open Issues in Local Star Formation, page 266:

hydrostatic equilibrium
hydrostatic equilibrium

(astronomy) an astronomical object with enough mass to achieve hydrostatic equilibrium, but not enough to initiate core fusion at any time in its existence. That is, it is rounded in shape and is smaller than a star. Planemos include planets, dwarf planets, and the larger moons of the Solar System (satellite planets), but also sub-brown dwarfs and rogue planets between the stars.

Gibor Basri
International Astronomical Union
University of California, Berkeley


fusor

Gibor Basri
International Astronomical Union
University of California, Berkeley
fusor (disambiguation)

Coined by Gibor Basri, Professor of Astronomy at the University of California, Berkeley, at the 2003 IAU conference; presumably fuse + -or.

(astronomy) A celestial body that, through self-gravity, is able to perform nuclear fusion within its core, at any point in its life. These include stars, stellar remnants, and brown dwarfs.

fuusori

celestial body that, through self-gravity, can perform nuclear fusion in its core


SED

SED (countable and uncountable, plural SEDs)

spectral energy distribution
spectral energy distribution#English

(astronomy, physics) Initialism of spectral energy distribution.


FRB

Fast Radio Burst
fast radio burst#English

(astronomy) Initialism of Fast Radio Burst.


ultraluminous

(astronomy) Very luminous, though less luminous than that classified as hyperluminous.


Dreyer

New General Catalogue
New General Catalogue

(astronomy, archaic) a Dreyer object — an entry/object in the New General Catalogue (NGC) compiled by J. L. E. Dreyer.


Dreyer

(astronomy, archaic) the Dreyer Catalogue — the NGC compiled by JLE Dreyer.


Mimas

From Ancient Greek Μίμᾱς (Mímās), earlier Μίμανς (Mímans).

Evidence suggests, for example, that Saturn's moon Mimas may have an ocean.

2021, Kevin Hand, Alien Oceans: The Search for Life in the Depths of Space, Princeton University Press, →ISBN, page 43:

(astronomy) The innermost of Saturn's classical satellites, marked by a giant impact crater (Herschel) on its surface.


Skat

(astronomy) The star Delta Aquarii in the constellation of Aquarius.


ECO

MECO

a different type of black hole replacement, that inspired the formulation of ECOs

magnetospheric eternally collapsing object

eternally collapsing object
eternally collapsing object#English

(astronomy, physics) Initialism of eternally collapsing object. (a type of black hole replacement, to avoid having gravitational singularities)


carbon planet

Proposed as a theoretical planet by Marc Kuchner.

(astronomy) A theoretical type of terrestrial planet that could form, if protoplanetary discs are carbon-rich and oxygen-poor.


curvaton

(astronomy) A scalar field associated with fluctuations in the curvature of space during inflation.


exomoon

Of course we can't detect exomoons now (or for a long while), but could planets like 51 Peg b have any moons? Wouldn't the star strip them off? I don't suppose there can be a moon around a planet that orbits in more time than it takes that planet to orbit its star.

2001 July 14, Robert Casey, “Moons around "hot Jupiter" exoplanets, possible?”, in sci.astro.research (Usenet), retrieved 2019-03-20, message-ID <mt2.0-23734-995099843@star.bris.ac.uk>:

Now we get exoplanets, dwarf planets, rogue planets, and (exo)moons. That's ok, but then comes the utter silliness: none of them are planets. Even those bigger than Jupiter aren't planets.

2006 August 27, Jens Egon Nyborg, “Re: It's official--Jupiter is now a dwarf planet!”, in rec.arts.sf.written,rec.arts.sf.science (Usenet), retrieved 2019-03-20, message-ID <xweIg.30$fR6.17@news.get2net.dk>:

(astronomy) A moon that is outside the Solar System (our solar system).


kination

(astronomy) Cosmological phase of the dominance of kinetic energy over potential energy. Coined by Michael Joyce in 1996 in the paper "Electroweak baryogenesis and the expansion rate of the Universe".


superhorizon

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(astronomy) Larger than the cosmological horizon


star chart

(astronomy) A map of the night sky used to identify and locate astronomical objects such as stars, constellations and galaxies.


sunlike

en-adj

sunlike (comparative more sunlike, superlative most sunlike)

more sunlike (comparative)
most sunlike (superlative)

a sunlike star


Beta Canis Majoris

From its Bayer designation Beta Canis Majoris.

(astronomy) The fourth-brightest star in the constellation Canis Major.


Gliese 581

(astronomy) A red dwarf star about 20 light years from the Solar System. Gliese 581 is notable due to at least two exoplanets that might be life-sustaining.


substorm

At times, however, energy builds up within the magnetic field until it suddenly breaks loose into what is called a substorm, releasing a burst of electrical current that turns the auroras into pulsing red, purple and white colors.

2007 January 23, Warren E. Leary, “Five New Satellites With a Mission of Finding a Source of Color in Space”, in New York Times:

(astronomy) A phenomenon in which a magnetotail becomes swollen and unstable.


magnino

(physics, astronomy) An ultralight fermionic species proposed to have condensed into a ferromagnetic state in the early universe


Oort cloud

A cloud-like structure, named after Dutch astronomer Jan Oort, who proposed it.

(astronomy) A roughly spherical region of space composed of comet-like bodies and other minor planets and asteroids that orbit distantly in a planetary system.


Hiʻiaka

(astronomy) The larger, outer moon of the dwarf planet Haumea.


LMS

en-noun

LMS (countable and uncountable, plural LMSs)

(astronomy) Initialism of low mass star.


areologist

(astronomy) One who studies the planet Mars.


areological

en-adj

areological (comparative more areological, superlative most areological)

more areological (comparative)
most areological (superlative)

(astronomy) Of or pertaining to the planet Mars.


parallel universe

en-noun

parallel universe (plural parallel universes)

non-parallelizable universe

mathematically incompatible; without a common superordinate wave function

Subjectively we perceive this as a single, unpredictable or ‘random’ outcome, though from the multiverse point of view all the outcomes have actually happened. This parallel-universe multiplicity is the real reason for the unpredictability of the weather.

1998 [1997], David Deutsch, The Fabric of Reality, New York: Penguin Books, →ISBN, page 202:

(sciences, science fiction, cosmology) A universe that exists separately alongside another universe, as part of a multiverse.


optical astronomy

(astronomy) Astronomy using infrared, visible, and/or ultraviolet wavelengths.


Lyrid

(astronomy) A shooting star or meteor observed as originating from the constellation Lyra, and belonging to the meteor shower seen each April.


crono-

From Ancient Greek Κρόνος (Krónos, “Cronus”).


stellify

en-verb

stellify (third-person singular simple present stellifies, present participle stellifying, simple past and past participle stellified)

stellifies (present singular third-person)
stellifying (participle present)
stellified (participle past)
stellified (past)

From Middle English stellifien (“to make into a star; glorify, deify”), from Middle French stellifier, from Medieval Latin stellificāre, itself from Latin stella (“star”) + faciō (“make, do”).

inh

An alternative way to stellify the planet may be to not collapse Jupiter, but instead to introduce a collapsed object into its core.

1989, Analog Science Fiction/Science Fact, 109: 75:

(transitive, astronomy) To turn into a star.


afterbody

(astronomy) A companion body that trails a satellite or spacecraft.


circummeridian

en-adj

circummeridian (comparative more circummeridian, superlative most circummeridian)

more circummeridian (comparative)
most circummeridian (superlative)

(astronomy) About or around the meridian.


cold trap

The impact of a large body in the oceans would inject large quantities of water through the tropopause cold trap into the stratosphere and lower mesosphere.

1983, Christopher P. McKay, Gary E. Thomas, “Formation of noctilucent clouds by an extraterrestrial impace”, in Geological Implications of Impacts of Large Asteroids and Comets on the Earth, →ISBN:

Since the tropopauses of these planets are very cold, there is effectively a cold trap, which in the absence of any other sources should keep the stratospheric water abundance very low, as discussed in Section 4.3.3.

2009, Patrick Irwin, Giant Planets of Our Solar System: Atmospheres, Composition, and Structure, →ISBN, page 97:

The heat input to polar areas prevents this global cold trap catastrophe from happening, but during ice ages, significant capture of the Earth's water in polar areas will occur.

2008, Donald Rapp, Assessing Climate Change, →ISBN, page 24:

The tropopause acts as a cold trap, dehumidifying the upper atmosphere and strongly limiting the opportunity for water vapor to escape or for hydrogen to build up in Earth's upper atmosphere through decomposition of water vapor.

2010, Raymond T. Pierrehumbert, Principles of Planetary Climate, →ISBN, page 547:

(astronomy) An atmospheric layer that is significantly colder than the adjacent layers both deeper and higher. It keeps ascending gases that have high melting points from escaping the atmosphere by freezing them to a solid which then drops back to the planet surface.


Oriental

Oriental (comparative more Oriental, superlative most Oriental)

more Oriental (comparative)
most Oriental (superlative)

/ɔːɹiˈɛntəl/

From Middle English oriental, from Anglo-Norman oriental, Middle French oriental, from Latin orientālis (“eastern”), from oriēns (“rising (of the Sun)”), present active participle of orior (“I rise”).

(astronomy, astrology) Pertaining to the eastern part of the sky; happening before sunrise.


sublunary sphere

en-noun

sublunary sphere (plural sublunary spheres)

(cosmology) In geocentric cosmologies, that region of the cosmos from the centre of the Earth to the moon, believed to comprise the four classical elements (earth, air, fire and water) and to be subject to generation and corruption.


subclump

(astronomy) A clump of dark matter in a subhalo.


subhalo

(astronomy) A subset of a halo (of matter or dark matter around a galaxy)


depointing

(astronomy) The practice of pointing an antenna or telescope slightly away from a direct line of sight in order to correct for parallax


pulsator

(astronomy) Any pulsating astronomical object


thermopause

(astronomy, meteorology) The boundary between the thermosphere and the exosphere in a planetary atmosphere.


HMXB

high-mass X-ray binary
high-mass X-ray binary#English

(astronomy) Initialism of high-mass X-ray binary: a binary star system that is strong in X-rays, and in which the normal stellar component is a massive star, and the compact X-ray-emitting component is a neutron star, black hole, or white dwarf.


LMXB

(astronomy) Initialism of low-mass X-ray binary: a binary star system that is strong in X-rays, and in which the normal stellar component is a main-sequence star, degenerate dwarf, or evolved star from the main sequence, and the compact X-ray emitting component is a neutron star, black hole, or white dwarf


IMXB

(astronomy) Initialism of intermediate-mass X-ray binary: a binary star system that is strong in X-rays, and in which the compact X-ray emitting component is a neutron star, black hole, or white dwarf.


cD

(astronomy) a type of giant elliptical galaxy


mesoplanet

(astronomy) a planet that is between the size of Mercury and Ceres

(astronomy) A habitable planet, such as Earth, that has a surface temperature of 0–50°C, optimal for much terrestrial life.


perihelium

(astronomy, obsolete) Synonym of perihelion


SXT

soft X-ray transient
soft X-ray transient#English

(astronomy) Abbreviation of soft X-ray transient.

soft X-ray telescope
soft X-ray telescope#English

(astronomy) Abbreviation of soft X-ray telescope.


HXT

hard X-ray telescope
hard X-ray telescope#English

(astronomy) Initialism of hard X-ray telescope.


approacher

Extensive upgrades to the Arecibo antenna will be completed this spring, providing dozens of Toutatis-quality detections per year, spacecraft-quality images of the closest approachers, and hundred-pixel images of dozens of main-belt asteroids ( 9 ).

1997 December 19, Erik Asphaug, “PLANETARY SCIENCE: Enhanced: New Views of Asteroids”, in Science, volume 278, number 5346, →DOI, pages 2070–2071:

We have some close approachers," he says, "but not one that would have an impact trajectory."

2005 June 3, Ted McClelland, “Something Big Is Out There”, in Chicago Reader:

(astronomy) An asteroid on a near-Earth trajectory.


ylem

Resuscitation of Middle English ylem, from Medieval Latin hȳlem, accusative of hȳlē (“matter, the fundamental matter of all things; the matter of the body”) (whence English hyle), a transliteration of Ancient Greek ὕλη (húlē, “wood; material, substance; matter”). The concept of “fundamental matter” – Ancient Greek πρώτη ὕλη (prṓtē húlē) – was propounded by the Greek philosopher Aristotle (384–322 B.C.E.).
The term ylem was first used in modern English in the paper “The Origin of Chemical Elements”, coauthored by Russian-American theoretical physicist and cosmologist George Gamow (1904–1968), American cosmologist Ralph Asher Alpher (1921–2007) and German-American nuclear physicist Hans Bethe (1906–2005), published 1 April 1948 in Physical Review. Alpher claimed to have found the word “in a large dictionary”, perhaps Webster’s New International Dictionary (2nd ed., 1934), which he referred to in a second 1948 paper (cited below). In a 1968 interview, Gamow also associated ylem with a Hebrew word he did not name; it remains unclear which word he was referring to.
The word ylem reappeared in popular books on science following the discovery in 1964–1965 of the cosmic microwave background, which had been predicted in 1948 by Alpher and Robert Herman (1914–1997), and again after the publication of images of the radiation composed from measurements by two satellites, the Cosmic Background Explorer (COBE) in 1992 and the Wilkinson Microwave Anisotropy Probe (WMAP) in 2003.

der

Very shortly after the beginning of the universal expansion, the ylem was a gas of neutrons only. [Footnote: According to Webster's New International Dictionary, 2nd Ed., the word ‘ylem’ is an obsolete noun meaning ‘The primordial substance from which the elements were formed.’ It seems highly desirable that a word of so appropriate a meaning be resurrected.]

1948 December 1, R[alph] A[sher] Alpher, “A Neutron-capture Theory of the Formation and Relative Abundance of the Elements”, in Physical Review, volume 74, number 11, College Park, Md.: American Physical Society, →DOI, →OCLC, page 1581, column 1:

Let us now consider the state of matter during the first minutes of the expansion process, when the temperature of the universe was many billions of degrees high. […] [T]he state of matter must be visualized as a hot gas formed entirely by nuclear particles; that is, protons, neutrons, and electrons. […] We will call this primordial mixture of nuclear particles "Ylem," [footnote: Pronounced: ī′lěm] reviving an obsolete noun which, according to Webster's Dictionary, means "the first substance from which the elements were supposed to be formed." Next we can ask what happened to the Ylem when its density and temperature began to drop as the result of the rapid expansion taking place in the young universe.

1952, George Gamow, The Creation of the Universe, New York, N.Y.: Viking Press, OCLC 999160; republished as New York, N.Y.: Viking Press, 1961, 2nd edition, OCLC 642243549, page 53

The ylem was the primordial flux of neutrons out of which all else emerged.

1959, James Blish, chapter 7, in A Clash of Cymbals [US title: The Triumph of Time] (Cities in Flight; 4), London: Faber and Faber, →ISBN, page 171:

He [George Gamow] surmised that that the universe began as a super-condensed raging inferno of protons, neutrons and electrons, which he and his colleagues called the ylem […] The internal pressures of the ylem caused it to expand outward extremely rapidly. After a few minutes the ylem cooled down sufficiently to allow the strong force to bind neutrons and protons together into deuterium nuclei. […] Then there was just enough time for some of the deuterium to fuse into helium before temperatures and pressures of the ylem became too diffuse to allow more fusions.

2008, Piers Bizony, “Part Eight, Ylem”, in Atom, Thriplow, Cambridgeshire: Icon, →ISBN, page 171:

cosmic microwave background
cosmic microwave background

(cosmology, now chiefly historical) In the Big Bang theory, the hot and dense plasma that made up the matter in the cosmos following the initial baryogenesis at an early stage of its expansion and cooling, from which the first atoms formed and photons decoupled. The emission of photons in this phase is regarded as the source of the cosmic microwave background.

National Aeronautics and Space Administration


Jupiter mass

(astronomy) A unit of mass equal to the mass of the planet Jupiter, used to express the mass of other planets. 1 M_J = 2 × 10²⁷ kg.


Earth mass

The mass of Jupiter is 318 M_🜨; its radius is 11 R_🜨.

(astronomy) A unit of mass equal to that of the Earth, used to express the mass of planets and similar astronomical bodies. 1 M_🜨 = 6 × 10²⁴ kg.


circumbinary

The effect of a reduced collision rate at large orbital radii on the formation timescale of planets is possibly explained by Alexander (2012) who suggests that circumbinary planets have more time to form than planets around single stars.

2014 Jan. 15, Stefan Lines et al., "Forming Circumbinary Planets: N-body Simulations of Kepler-34," The Astrophysical Journal Letters, vol. 782, L11 (retrieved 11 Feb 2014)

(astronomy) Having an orbit around both stars in a binary star system, or relating to such an orbit.

circumbinaire

having an orbit around binary stars, or relating to such an orbit


strewnfield

[W]e report the detailed circumstances of the fall and the recovery of all documented Tagish Lake fragments from a strewnfield at least 16 km long and 3 to 4 km wide.

2006, A. R. Hildebrand et al., "The fall and recovery of the Tagish Lake meteorite," Meteorics & Planetary Science, vol. 41, no.3, p. 407 (abstract)

(astronomy) An area on the surface of the earth, usually having an elongated oval shape, containing rocky fragments which detached from a disintegrating meteor as it streaked through the portion of earth's atmosphere above the area.


inner core

(planetology) The solid material found in the centre of some planets at extremely high temperature and pressure, distinct from the liquid outer core.

(geology) The innermost part of the Earth, believed to be made of a nickel-iron alloy.


BBN

en-noun

BBN (countable and uncountable, plural BBNs)

Big Bang nucleosynthesis
w:Big Bang nucleosynthesis

(astronomy, physics) Initialism of Big Bang nucleosynthesis.


Cracovian

/kɹəˈkəʊvɪən/

Formed as Latin Cracōvia (“Cracow”) + English -an (suffix forming adjectives with the sense “of or pertaining to”). Equivalent to the Latin Cracōviānus.

(astronomy, geodesy) a clerical convenience in solving systems of linear equations by hand.


elve

From e(mission of) l(ight and) v(ery low-frequency perturbations from) e(lectromagnetic pulse sources), and to avoid clashing with the acronym ELF (extremely low frequency) used in the same field of science.

It is likely that the first elve was recorded with the Space Shuttle low-light camera.

2006, Martin Füllekrug, Eugene A. Mareev, Michael J. Rycroft, Sprites, elves and intense lightning discharges, page 37:

(astronomy, meteorology) A rapidly expanding disk-shaped region of red luminosity in the ionosphere, lasting less than a thousandth of a second, which occurs high above energetic cloud-to-ground lightning of positive or negative polarity.


nonagesimal

(astronomy) The middle to highest point of a part of an ecliptic that is above the horizon at any period of time.


metagalaxy

(astronomy) Any very large-scale organized collection of galaxies.

總星系 /总星系

any very large-scale organized collection of galaxies


telescopic star

telescopic star (plural telescopic stars)

(astronomy) a star that is fainter than 7th magnitude in apparent magnitude, and therefore in most cases is not visible to the naked eye.


retrograde motion

retrograde motion (countable and uncountable, plural retrograde motions)

(astronomy) Motion of a body (either real or apparent) in a direction opposite to that of its normal motion, or to that of other similar or related bodies

retrográd mozgás

motion of a body opposite to that of related bodies


radio galaxy

(astronomy) Type of galaxy that is very luminous at radio wavelengths.


Circe

(astronomy) 34 Circe, a main belt asteroid.


LRN

luminous red nova
luminous red nova#English

(astronomy) Initialism of luminous red nova: an astronomical event, believed to be a type of stellar explosion, intermediate in power between a nova and a supernova, and such that as the explosive debris expands it reddens and cools, unlike a nova or supernova, in which thinning explosive debris exposes hotter interior layers.


late-type star

(astronomy) a star of spectral type K or M


early-type star

early-type star (plural early-type stars)

(astronomy) a star of spectral type O, B, A, or F0 to F5.


armilla

Borrowed from Latin armilla. Doublet of armill.


solar nebula

solar nebula (plural solar nebulae or solar nebulas)

solar nebulae (plural)
solar nebulas (plural)

(astronomy) A disc-shaped cloud of gas and dust left over from the formation of the Sun.


deleptonization

(physics, astronomy) The loss of leptons from a supernova or rotating protoneutron star


fluctosphere

(astronomy) The almost non-magnetic portion of the lower chromosphere.


inspiral

(astronomy) Describing the paths of a pair of astronomical bodies (e.g. binary stars or black holes) that are spiralling in towards each other, losing energy to gravitational waves.


inspiral

en-verb

inspiral (third-person singular simple present inspirals, present participle inspiraling or inspiralling, simple past and past participle inspiraled or inspiralled)

inspirals (present singular third-person)
inspiraling (participle present)
inspiralling (participle present)
inspiraled (participle past)
inspiraled (past)
inspiralled (participle past)
inspiralled (past)


intercloud

As the sun moves in its path through the galaxy, it will not always be immersed in the tenuous intercloud region of the interstellar medium.

1977, American Geophysical Union, Reviews of Geophysics and Space Physics, volume 15:


longward

en-adj

longward (comparative more longward, superlative most longward)

more longward (comparative)
most longward (superlative)

The profiles of both lines are extremely asymmetrical, which we have found to be caused by very broad diffuse interstellar bands (DIBs) in the longward wing of H#92;beta and the shortward wing of H#92;alpha.

2015, Nolan R. Walborn, Hugues Sana, Christopher J. Evans, William D. Taylor, Elena Sabbi, Rodolfo H. Barbá, Nidia I. Morrell, Jesús Maíz Apellániz, Alfredo Sota, Philip L. Dufton, Catherine M. McEvoy, J. Simon Clark, Nevena Markova, Krzysztof Ulaczyk, “Broad Balmer Wings in BA Hyper/Supergiants Distorted by Diffuse Interstellar Bands: Five Examples in the 30 Doradus Region from the VLT-FLAMES Tarantula Survey”, in arXiv:

the H₂S band is centered slightly longward of the feature in the Quaoar spectrum.

(physics, astronomy) Near, or oriented toward, the longer wavelengths of a range.


postbounce

(astronomy) Describing the period following the bounce of a collapsing stellar core


presupernova

(astronomy) Describing the period, and the events, prior to a star becoming a supernova


protoneutron

protoneutron star
protoneutron star#English

(astronomy) Only used in protoneutron star


protoneutron star

en-noun

protoneutron star (plural protoneutron stars)

(astronomy) A star which is cooling and contracting to become a neutron star.


ringdown

gravitational wave
gravitational wave#English

(astronomy) The stage in a black hole merging event where the gravitational wave amplitude reaches its peak.


superbubble

LL-Q1860 (eng)-Flame, not lame-superbubble.wav

interstellar medium
interstellar medium#English

supernova bubble
supernova bubble#English

(astronomy) A very large region of space, relatively free of matter, carved out of the interstellar medium by the combination of multiple supernova bubbles resulting from supernovae.


virialized

en-adj

virialized (comparative more virialized, superlative most virialized)

more virialized (comparative)
most virialized (superlative)

(astronomy) That has undergone virialization


virialization

en-noun

virialization (usually uncountable, plural virializations)

(astronomy) The formation of a dynamic equilibrium in a system of collisionless particles modelled as being subject only to Newtonian gravity (galaxy, other stellar system, or galaxy cluster).


GL

(astronomy) Misspelling of Gl., the prefix for Gliese catalog of nearby stars


Pandoran

en-adj

Pandoran (comparative more Pandoran, superlative most Pandoran)

more Pandoran (comparative)
most Pandoran (superlative)

(astronomy) Of or relating to the Saturnian moon named for Pandora.


MTC

Coordinated Mars Time
Coordinated Mars Time#English

(astronomy) Abbreviation of Coordinated Mars Time.


AMT

(astronomy) Abbreviation of Airy Mean Time.


asteroseismic

asteroseismic (comparative more asteroseismic, superlative most asteroseismic)

more asteroseismic (comparative)
most asteroseismic (superlative)

(astronomy) Of or pertaining to asteroseismology.


galaxian

(astronomy) Of or pertaining to a galaxy


prestellar

The first flex of the membrane, leading to the clench, begins at the extreme interior margins of Path Terrulian in the 78th Thema, a cold, pre-stellar dust cloud fringed with cooling, iron-hearted stars and vast numbers of stony and icy planets and asteroids.

2013 March 19, Greg Bear, String 25, in Halo: Silentium (Forerunner Saga; 3), New York: Tor, →ISBN, page 212:

(astronomy) Describing the matter and conditions involved in the formation of a star


coorbital

coorbital (comparative more coorbital, superlative most coorbital)

more coorbital (comparative)
most coorbital (superlative)

(astronomy) Describing bodies that share the same orbit.


corotational

(astronomy) That rotates in conjunction with another body.

corotazionale

that rotates in conjunction wit another body


protostellar

(astronomy) Of or pertaining to a protostar.


Brunhild

From German Brunhilde, from Middle High German Briunhilde, from Old High German *Brunnīhilta, from Proto-Germanic *Brunjōhildiz (from *brunjǭ (“breastplate”) + *hildiz (“battle, fight”)).

der

(astronomy) 123 Brunhild, a main belt asteroid, named after the mythological figure.


braneless

(physics, astronomy) That does not involve a brane


galactocentric

a galactocentric coordinate system

a galactocentric orbit

(astronomy)
Having a galactic center at its center.

(astronomy)
Having an entire galaxy at its center.

(cosmology) Of or relating to galactocentrism, the theory according to which the Milky Way is at or near the center of the Universe.


subphotospheric

(astronomy) Occurring beneath the photosphere


supersoft

en-adj

supersoft (comparative more supersoft, superlative most supersoft)

more supersoft (comparative)
most supersoft (superlative)

LL-Q1860 (eng)-Flame, not lame-supersoft.wav

(astronomy) Describing astronomical X-rays of very low energy.


accretor

(astronomy) An astronomical body (such as a star) that accretes surrounding material


apogalacticon

(astronomy) The point in the orbit of a star at which it is furthest from the centre of its local galaxy


perigalacticon

From peri- + galactic + -on, alternative form of -ion.

(astronomy) The point in the orbit of a star at which it is closest to the centre of its local galaxy


gigaparsec

(astronomy) An astronomical unit of distance equal to 10⁹ parsecs.


neutronization

(physics, astronomy) The process, such as within a collapsing star, in which protons and electrons fuse to form neutrons and release neutrinos.