The cause of a bright kaboom that led to the classification of a new type of space explosion may have been revealed.
An analysis of the event dubbed "the Cow" suggests that it was an unusual type of core-collapse supernova that led to the formation of a compact Cosmic object.
astronomer Dheeraj Pasham of MIT's Kavli Institute for Astrophysics and Space Research says that they have likely discovered the birth of a compact object in a supernova.
This happens in normal supernovae, but we haven't seen it before because it's so messy. We think that this new evidence will lead to the discovery of baby black holes or baby neutron stars.
The Cow was found on June 16th, and was fascinating. It was around 100 times brighter than a typical supernova. The Cow was thought to be coming from the center of the universe. Astronomers were shocked when they realized it was from a galaxy 200 million light-years away.
More explosions with a similar profile have been identified since the Cow. Fast Blue Optical Transients, of FBOTs, were named after them, and they have been looking for what causes them.
A black hole consuming another dense object, such as a white dwarf, or a black hole stripping material from a passing star could be an option.
A type of core-collapse supernova, in which a stellar core, no longer supported by the outward pressure of fusion, collapses under its own gravity into an ultra-dense object, was one of the options.
The most likely way to determine which of these scenarios was the most likely was to look at the X-ray data.
The signal was close and bright in the X-rays, which got my attention. The first thing that comes to my mind is that some really energetic phenomenon is going to generate X-rays. I wanted to see if there is a black hole at the core of the cow.
The data they analyzed was from the International Space Station. The object was observed for about 60 days to collect X-ray data.
The researchers found that something within the Cow was releasing a burst of soft X-rays for the entire 60-day observing period. The X-rays can't be larger than 1,000 kilometers, which is 622 miles, because of the periodicity.
A black hole or a neutron star is the only thing that can be that small.
The object's mass is constrained by the signal's strength. It can't be more than 800 times the mass of the Sun. This also suggests a collapse.
The periodic pulsations can be produced by different mechanisms. If it's a neutron star, the spin rate could be as little as 4.2 milliseconds. If the black hole is a black hole, the emission could be produced by the material falling back into the black hole.
There are still questions that need to be answered with either model. It is difficult to explain the narrowness of the emissions. It is difficult to explain the X-ray brightness and stability of a black hole.
Future studies of the Cow and other FBOTs could help resolve some of the outstanding problems.
They could help us understand some of the most extreme objects in the Universe.
There's excitement when there's a new phenomenon that could tell something new about the Universe.
We have shown that we can study the pulsations in a way that is not possible in the optical. This is a new way to understand the newborn objects.
Nature Astronomy has published the research.
