"astronomical transient" meaning in English

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        "A localized discrete transient optical spectrum event at astronomical distances."
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        "(astronomy) A localized discrete transient optical spectrum event at astronomical distances."
      ],
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        "en:Transient astronomical event"
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  "word": "astronomical transient"
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        "A localized discrete transient optical spectrum event at astronomical distances."
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        "(astronomy) A localized discrete transient optical spectrum event at astronomical distances."
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