Gravitational-wave candidate
S251117bc
Two black holes probably merged about 7 billion light-years away.
This line is written from the event's own fields, not translated from the source.
Each field explained
- Status
- Preliminary
An automatic alert sent within minutes of the signal. Later analysis can change these numbers, confirm the event with a GW name, or withdraw it.
- Significance
- Low significance
Low significance: shared openly, but below the bar for a significant alert. Many of these are noise.
- What it was
- Two black holes69.2%
- Noise in the detectors30.8%
- Two neutron stars0%
- A neutron star and a black hole0%
How likely each kind of source is, from the latest public alert. The numbers come from how the signal looked, not from a person's judgement.
- Distance
- About 7 billion light-years (2,100 ± 890 megaparsecs)
Estimated from how loud the signal was: a quieter wave came from further away. The spread is large in a first alert, and it shrinks as the analysis is refined.
- False alarm rate
- About once every 21 days
How often noise alone would make a signal at least this strong. The rarer, the more likely it is real.
- Detectors
- LIGO Hanford and LIGO Livingston
The observatories that saw the signal. More detectors means a better position on the sky.
- When
When the signal reached Earth, in UTC.
- Latest alert
- Preliminary
Each alert replaces the numbers of the one before it.