A neutron star: A neutron star is very small, relatively speaking. Most don't have a radius any bigger than about 7 miles, but the cool thing about them is their incredible density. While small in size, they can actually have a mass that is close to two times that of our Sun.
A black hole: A black hole is really about the math. A complex math formula is calculated in terms of its gravitational pull and how much velocity it has. When a star explodes, the sheer power of that event can create a vortex that spins at a high speed, creating a pull on anything around it.
A pulsar: These are awesome. A pulsar is the magnetic field that surrounds a neutron star and some of them are so powerful they can actually disrupt the spacetime continuum. Yes, that spacetime thing is real. Sometimes referred to as the "fabric of spacetime" or simply spacetime, it's a concept where a mathematical model is used to weave together the description of time and space. It's how physicists talk about the way space and time interact.
With all of that going on, imagine what it must be like to have witnessed part of this process. Joeri van Leeuwen, an astrophysicist at the Netherlands Institute for Radio Astronomy, and University of Amsterdam, led a team that sort of did see it, in a way. They were able to collect data from binary pulsar system J1906 and use that data to actually measure a time warp. Yes, a real time warp. As the Doctor would say, "A big ball of wibbly-wobbly, timey wimey stuff!"
25,000 light-years away from earth J1906 died out and disappeared from view. It's unusual because it's a binary pulsar system, essentially a two-fer. When a supernova happens, it's rare that a star will be able to hang on to a companion, but J1906 is comprised of two super dense stars. One pulsar spins, much like the Earth does every 24 hours, and it also orbits its companion. The radio waves thrown off by both stars sweep across space in a way described by astronomers as much like the beam from lighthouse sweeps across the ocean.
According to the team's research it was actually swallowed by a warp of the spacetime fabric
In an interview with Space.com, study co-author Duncan Lorimer of West Virginia University explained, "The companion is so massive that it creates a huge warp in the fabric of spacetime, like a bowling ball on a thin sheet. Its spin axis shifts ever so slightly, and it precesses, or wobbles like a spinning top. This wobbling is known as "geodetic precession."
Once the team was able to quantify the change in the axis of the pulsar's spin, their mission became measuring the mass of the two pulsars before they disappeared into the warp.
The study has been accepted for publication in the Astrophysical Journal. Check out the video below for an explanation from NASA experts on what exactly a pulsar is.