double star system planet sun nemesis 615274main_Kep35_Garlick_full An illustration of a double-star system and an exoplanet. NASA; Mark A. Garlick/

A new model on how stars are formed has added weight to the hypothesis that most — if not all — stars are born in a litter with at least one sibling.

Our own star at the center of the solar system is probably no exception, and some astronomers suspect that the sun's estranged twin might be the evil one, blaming it for the death of the dinosaurs.

After analyzing data from a radio survey conducted on a dust cloud in the Perseus constellation, two researchers from UC Berkeley and the Harvard-Smithsonian Astrophysical Observatory have concluded all sun-like stars are probably born with a companion.


An evil force born in darkness

molecular cloud barnard 68 space dust gas dark spot fors vlt eso Molecular cloud Barnard 68, a dense, dark region of gas and dust that absorbs practically all visible light. FORS Team/8.2-meter VLT Antu/ESO


The "born together" hypothesis has been the favoite, and simulations developed in recent decades have shown almost all stars could be born as multiples that often spin away on their own.



triple star system birth nrao16cb18c_nraoTobin750 A triple-star system being born inside the Perseus molecular cloud. Bill Saxton; ALMA (ESO/NAOJ/NRAO); NRAO/AUI/NSF


The VANDAM survey allowed for a census of stars younger than half a million years old called Class 0 stars — mere babies in star terms — and stars a little older between 500,000 years and 1 million years, called Class 1.







The sun's missing twin

sun NASA

If most stars are born with a partner, where's ours?


So if the sun has a twin, it's almost certainly not easily visible in our neighborhood.

But there is an hypothesis that our sun has a dark twin that likes to swing by every now and then, and stir things up.


An astronomer from the University of California Berkeley named Richard Muller proposed 23 years ago that a red dwarf star 1.5 light-years away could periodically travel through the icy outer limits of our solar system, stirring up material with its gravity, knocking a few more space boulders our way.

A dim passing star such as a brown dwarf could also explain other anomalies at the fringes of our solar system, such as the odd, wide orbit of the dwarf planet Sedna.

There's no sign of Nemesis, but a long lost binary partner for our sun could fit the bill.


In which case, our sun would have gathered the lion's share of dust and gas it seems, leaving its twin dark and stunted.

No wonder it's a little pissed off.

