There is a belief between astronomers that somewhere out there in our galaxy, the Sun has a long-lost twin. This star would not only be born in the same stellar nursery but would also be a binary companion made of the same elements of our own star. Only a few candidates for solar siblings have been identified. One of these candidates has been found roughly 184 light-years away and is called HD 186302.
From binary to solitary
Stars get flung out on their own into the galaxy but according to astronomers, most of them have at least one other companion. It’s estimated up to 85% of all stars could be in binary pairs and over 50% of all Sun-like stars could also have pairs.
But the Sun is a solitary star which makes it stand out among the others. On the other hand, there’s evidence that the Sun did have a twin, but we don’t yet know what could’ve happened to change that fact.
Our star’s lost twin
A team of researchers from the Instituto de Astrofisica e Ciências do Espaço (IA) in Portugal have made a miraculous discovery. A possible twin called HD186302 – a star that is almost identical to the Sun.
It’s a G-type main-sequence star just a little bit bigger than the Sun and around the same surface temperature and luminosity. It also has very similar chemical abundances and age, around 4.5 billion years old.
Understanding our galaxy better
Every stellar sibling identified is another step closer to figuring out exactly where the Sun was born and to unraveling the history of our Solar System. The only place that has formed life is our Solar System meaning that the size, age, temperature, luminosity, and chemical composition of the Sun are all capable of sustaining life.
Stellar twins with these same qualities could have also developed life. Astronomer Varden Adibekyan of IA is hopeful that this new sibling candidate could be hiding an Earth 2.0 but only further research can tell us for sure whether our future is currently orbiting this new hope.