Astrophysicists and astronomers still have more to learn about the formation and evolution of stars, whether they like to admit it or not. The new discovery of researchers from the Center of Astrophysics | Harvard & Smithsonian is represented by a new type of binary star, according to Phys.org. Finding binary stars is not something new, indeed, but the existence of this one was long theorized.
To be more precise, postdoctoral fellow Kareem El-Badry is the man responsible for the discovery. He did it using data from astronomical surveys and also observations made with the Shane Telescope at Lick Observatory from California.
A discovery that astronomers were hoping for
El-Badry declared, as quoted by Phys.org:
We have observed the first physical proof of a new population of transitional binary stars,
This is exciting; it’s a missing evolutionary link in binary star formation models that we’ve been looking for.
White dwarfs form when stars die. In some rare situations, a star can collapse and become an extremely low mass white dwarf (ELM). But there’s a big puzzle here to unravel: the calculations regarding stellar evolution seem to show that all of the ELM white dwarfs are over 13.8 billion years old. That would make them even older than the Universe itself, considering that most astronomers agree that the Big Bang took place 13.7 billion years ago.
El-Badry confirms it by saying, as quoted by the same source mentioned above:
The universe is just not old enough to make these stars by normal evolution.
But there’s one way an ELM white dwarf can form, as astronomers realized: being helped by a nearby companion star, together forming a binary star. The gravitational pull of the companion could devour the other star in less than 13.8 billion years until it becomes an ELM white dwarf.
Feel free to read the full article on Phys.org!
The findings were also described in the Monthly Notices in the Royal Astronomical Society.