Astrophile: Binary stars that form like fraternal twins – space – 14 January 2014 – New Scientist January 14, 2014Posted by sandyclaus in Drake Revisited.
Astronomers have debated how binary stars, which make up about half of all sun-like stars in the galaxy, form and grow up. Some argue binaries are like twins, whether identical – beginning their existence as one entity and dividing in two early on – or fraternal – both forming from scratch in the same proto-stellar disc. Others think they\’re more like lovers who found each other later in life, migrating across interstellar space until gravity joins them for good.
Now astronomers have snapped their first-ever baby photos of binary stars, showing that the twin model is correct, at least sometimes. The protostars in question won\’t have finished forming for another million or so years, and only possess about 20 per cent of their ultimate mass, but their prenatal conditions offer a compelling explanation for the formation of binary systems in general.