When astronomers look at the heavens, they are not just looking for objects, whose existence we already know. They are also looking for evidence of physical phenomena, which, in our opinion, must exist, but have not yet been found. When this equation is added to a variety of factors — the vastness of space, the length of time our research and the current quality of our tools — there is a lot of stuff that we want to see, but not yet seen. The rarer it is found in the Universe, the harder it is to see, that’s the law.
Perhaps recently, we found one of the most difficult to detect objects — an incredibly rare neutron star, resulting from the collision of two white dwarfs.
What would happen if two white dwarf collide?
It is believed that stars that have enough mass to become neutron stars (almost all) end up white dwarfs. White dwarfs are the remains of stars, consisting of extremely dense degenerate matter. Their maximum stable mass of about 1.4 solar masses. This is known as the Chandrasekhar limit. White dwarf star that gains enough mass to overcome this limit, so massive that the pressure of the degenerate electrons in the core of the star is insufficient to resist its own gravitational samaritaine. At this point, the star explodes and becomes a neutron star or a black hole in classical type 1a supernovae.
Or at least it should be. But scientists have discovered a stellar object J005311 with an incredibly rare properties. This is a bright infrared star located inside of a gas cloud emitting visible light. It is 40,000 times brighter than the Sun (in the infrared range) and produces a powerful stellar wind that moves at the speed of 16 000 km/s. a Typical solar wind speed in the biggest star is ~2000 km/s is to help you understand how fast the star rotates.
“First of all, these results show that mergers of white dwarfs happen,” says study co-author Goetz Gravener, an astronomer at the University of Bonn. “Secondly, it shows that some of these mergers do not end in an explosion.”
When the star is at the final stage of her life, she begins to use for the synthesis of other materials other than hydrogen. What kind of materials it is able to take for synthesis is determined by its density. The collision of two white dwarfs dramatically increases the density of the target, allowing the synthesis of more heavy elements. This is expected to trigger increasing the reaction, which will blow the star to pieces, but this did not happen in the case J005311. Instead, the collision of two white dwarfs gave enough heat to ensure ignition of the carbon without an explosion. As the star burns, it generates enough thermal pressure to prevent collapse and supernova, which could occur otherwise. It is incredibly rare relative to the expected behavior of a pair of colliding white dwarfs.
And the temperature and wind speed, circling currently around J005311, suggest that this object is actually approached the end of his life. Given that the current weight is expected to be above the Chandrasekhar limit of, and life expectancy is only thousands of years, there is a very good chance that we caught J005311 for a tiny period of time, when you really have the opportunity to observe her. When a star explodes, it will probably create a supernova type 1C maximum luminosity.
If you have not seen, by the way, so it looks like a real black hole. And in our Zen is even more of any interesting stuff.