Scientists from the Jet Propulsion Laboratory have found a brown dwarf, which has been given the nickname “Accident.” He became the first representative of ultra-old brown dwarfs, which were previously unknown.
Astronomers knew about brown dwarfs earlier – these are objects that can not be attributed to stars or planets. They form like stars, but they don’t have enough mass to start nuclear fusion – the process that makes stars shine.
Astronomers believed they knew brown dwarfs well until they discovered an object called the Accident. The atypical brown dwarf was discovered by pure chance: it was not recorded during routine surveys, since it did not resemble any of the 2,000 previously discovered brown dwarfs in the solar system.
Usually brown dwarfs cool down and their brightness begins to change. But Accident’s typical wavelengths were weak, which meant the object was very cold and old. Its approximate age is between 10 and 13 billion years, which is about twice the normal average age of a brown dwarf. The object is approximately 50 light-years away.
This means that “Accident” was formed when our galaxy was much younger and had a different chemical composition. At the time of its formation, there was almost no carbon in the solar system: this means that now there is very little methane in the atmosphere of the superold brown dwarf.
If so, then, according to the authors, there should be many more ancient objects in our galaxy. To do this, astronomers need to change the approach to finding them.