LIGO+Virgo saw something unknown

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Summary:

LIGO and Virgo saw what looks like a very short gravitational event of unknown origin.

Main Question or Discussion Point

Not much is known so far. This is the notification from LIGO/Virgo and here is some raw data. Things I gathered from other sources (Twitter 1, Twitter 2, Reddit, ...):

It was a very short burst seen by all three detectors, with a false alarm rate of 1 per 25 years - a good chance this is something real. The burst was 14 milliseconds long and the fitted central frequency is 65 Hz, which means they had just about a single cycle in the signal. Most likely it won't look like a sine wave, it will probably look like a short peak, maybe two peaks in opposite directions (depending on how they define the duration), and then potentially some smaller oscillations afterwards. It was triggered by a system looking for intermediate mass black holes (heavier than stars but lighter than galactic black holes) but it is unclear if one of these was involved. It came roughly from the direction of Betelgeuse but the star is still there - telescopes are searching through the area to see if there is something new. Here is a map where people have looked.

Expect more updates in the following days.
 

Answers and Replies

  • #2
berkeman
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Would a near-miss by two Black Holes cause something like that, as opposed to the chirp from a merger?
 
  • #3
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A very eccentric orbit of two black holes is among the options discussed. It can't be too close, otherwise they would lose too much energy and merge.
 
  • #4
MathematicalPhysicist
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Galactic warfare... gotta be! :oldbiggrin:
 
  • #5
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Galactic warfare... gotta be! :oldbiggrin:
Or Thanos playing black hole bowling again...
 
  • #6
Bandersnatch
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  • #7
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The red ellipses are contours from LIGO/Virgo. The two larger ellipses are the 90% confidence region (by construction in 90% of the cases the source should be in them - this doesn't mean it has a 90% probability in this specific case however), the smaller one looks like the 68% region ("1 sigma"). You can check and uncheck the follow-up instruments to see what is what. As an example ZTF created the big blue rectangle areas.
 
  • #8
jambaugh
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Could it be (speculating wildly without even seeing data) a three body phenomenon where a temporary obit occurred? One body guides hyperbolic mass into a short orbit only to slingshot it out again? But controlling body's gravitational broadcasts outside the bandwidth of the detection?

[edit: And if I'm right call it a "wolf whistle phenomenon!" if I may!!!]
 
  • #9
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Any chance it's related to a core contraction leading to neon or oxygen-burning (or whatever stage it's at) ?
 
  • #10
jim mcnamara
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Let's not speculate. Until we get more information, more speculation post will get this thread moved out of the science forums and in to science fiction.

The problem is this topic is super interesting.... but control your urge to guess.

Thanks!
 
  • #11
Bandersnatch
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The red ellipses are contours from LIGO/Virgo. The two larger ellipses are the 90% confidence region
I still don't get it. Why are there three of those contours, but only one is surveyed with follow-up instruments (other than SWIFT)?
And why is Betelgeuse being mentioned if neither encompasses that region?
 
  • #12
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There are two separate regions in the sky that fit reasonably well to the observations. The left one in the image fits better, that's why it is studied more.
And why is Betelgeuse being mentioned if neither encompasses that region?
Because it's an interesting star people have heard about. It is not completely incompatible with the sky localization.
 

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