“We got the alert on August 17th that they had detected at very high confidence a neutron star merger and we discovered very quickly it was going to be possible to try to find an optical counterpart to it using our observatories in Chile,” Dr Maria Drout, Hubble and Carnegie-Dunlap Fellow at the Carnegie Observatories, told IFLScience.
With her colleagues and many astronomers around the world, they looked at the candidate sources within the area of the sky that the LIGO and VIRGO collaboration suggested as the likely origin for GW170817. The region was not enormous but it still contained a large number of galaxies.
“Our colleagues to put together a list of a hundred galaxies that we were going to search that night. And as it happens the new source was found in the ninth galaxy that was on our list,” Dr Drout added.
“Using all our telescopes on the object, you can see all the different colors and it really tells you a lot about the physics. It looked like something that was very young; a very young, very hot new object. So it was either the source or it was something else that had just exploded recently.”
The object was confirmed as the source of the gravitational waves and observatories across the world and in space were able to learn a lot about the event.
“Such small localization means that we could understand from which galaxy and where in that galaxy it happened. And once we had a counterpart in one wavelength we can do a search across the spectrum all the way from radio to the X-rays,” Dr Raffaella Margutti from Northwestern University told IFLScience.