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My question is straight forward. Is a kilonova bigger than a supernova?

Update

How does a kilonova differ from a nova in terms of...

  • luminosity
  • duration
  • energy
  • volume of space occupied by the ejecta
  • speed of the ejecta
  • other metrics?
daveloyall
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    How would you define "bigger"? More luminous? More energetic? Longer-lasting? – HDE 226868 Oct 18 '17 at 00:22
  • Thanks, HDE226868! I think I get it. Your comment, the answer PeterErwin provided, and the link uhoh provided have given me a picture of what kilonovas are like. I refined the question for the sake of the site... I left out supernovas and "hypernovas" (just learned about the latter today) though maybe that info could go here, too. Or maybe this question is answered well enough already. – daveloyall Oct 18 '17 at 14:21
  • Kilonova sounds a lot like supermoon; mostly journalistic in nature. If you take it literally, it means a thousand times as much of something, in this case "nova". – Wayfaring Stranger Oct 18 '17 at 16:40
  • Wayfaring Stranger -- That is the original intended meaning: roughly 1000 times as much energy as a (classical) nova. – Peter Erwin Oct 22 '17 at 09:01

1 Answers1

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Although it's a little tricky to say what "bigger" means in this context, the answer is, in most senses, no.

A supernova puts out about ten to a hundred times as much energy in the form of light, and hundred or more times as much matter is ejected. (A core-collapse supernova undoubtedly puts out much more energy in the form of neutrinos as well.) What matter is ejected by a kilonova does go out faster (30-60,000 km/s, versus about 10,000 km/s for supernova ejecta).

On the other hand, a kilonova puts out much more energy in the form of gravitational waves, so they're bigger in that sense.

Peter Erwin
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