The ABC, reporting on the announcement of gravitational wave GW170817, explained that for the first time we could identify the precise source of a gravitational wave because we also observed the event in the electromagnetic spectrum. It notes however that the gamma ray burst detected by the FERMI space telescope was observed nearly two seconds later than the gravitational wave.
Did the gamma ray burst actually arrive at Earth two seconds after the gravitational wave, or is this time delay just some kind of observational artefact?
If the delay is real, what is its cause? Is the delay due to the gamma ray burst somehow being slowed, or was it 'emitted' at a different time in the merger event?
What does a delay even mean when the gravitational wave was detected for over 100 seconds? Is it a delay from peak GW to peak gamma ray?
No comments:
Post a Comment