The Sun May Have an Evil Twin With a Flare for Mass Extinction

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NASA's Solar Dynamics Observatory snapped this view of the sun fading into shadow as it slips behind the Earth from the spacecraft's vantage point on March 29, 2011. . Solar Dynamics Observatory /NASA/GSFC

Not every sun is an only child. In fact, the universe often gives birth to a litter of stars. And the brightest light in our solar system may be no exception.

In fact, a new scientific model lends weight to the theory that the sun may have a brother, and his name is Nemesis.

The tale of these solar siblings may play out on a vast, cosmic stage — with epic consequences for life on Earth.

Scientists from from UC Berkeley and the Harvard-Smithsonian Astrophysical Observatory came up with the new model after studying data collected from the Perseus constellation — a sequence of stars millions of light-years away.

The data suggests stars like the sun typically have a consort, another star locked in orbit, commonly called a binary. The sun’s binary may be responsible for wreaking havoc in our solar system, including snuffing out life on Earth every 26 million years or so.

Yes, the sun may have a brother. And, unlike our favorite fiery orb, he didn’t graduate as valedictorian from star academy and go on to breathe life into this planet. Instead, he went traveling, possibly to find himself, and he only comes for a visit to burn the place down.

It's hard to shake your nemesis

An illustration of the inner solar system's planets' orbits around the sun
An illustration of the inner planets of our solar system orbiting around the sun. Vadim Sadovski/Shutterstock

It wouldn’t be the first time scientists have speculated about the existence of a long-lost sun with a flare for mass extinction.

As noted in, scientists dangled the second sun theory back in the 1980s. They were looking for reasons why mass extinctions seemed to follow a certain timetable — roughly every 26 million years.

Stumped for an Earthbound answer, they turned to the heavens, as humans are wont to do.

In 1984, Richard Muller of the University of California theorized that a red dwarf star traveling along an extended orbit, would occasionally darken our doorway. Along the way, the visitor may bluster through a field of icy rocks just beyond Pluto called the Oort cloud. Some of those rocks may be sent hurtling toward the inner solar system as comets.

Big, explosive, dinosaur-decimating comets. And that, according to the by-no-means-proven theory, accounts for the 26-million-year catastrophe gap.

An artist's rendering of the asteroid widely credited with wiping out the dinosaurs.
An artist's rendering of the asteroid widely credited with wiping out the dinosaurs. NASA

So what relation does this rogue star have to our benevolent beacon of life?

Well, that infrequent caller may be a binary star locked in a wide orbit with our own sun, basically following a very long orbit that takes it to the back alleys of the solar system and then, disastrously, this way again.

In other words, he’s the brother who rarely visits, but when he does, he can’t leave soon enough.

Nemesis may not be nearly as bright and formidable as our own sun — its size and vast distance from us may be a reason why no one has been able to detect it — but it turns out there’s a lot for a star to trip over in our solar system.

And, according to some reports, we may be due for another visit anywhere from 300 to 2,000 years from now.

Like us, the sun can't possibly be too excited about little brother coming around to undo all his good work.

Hi Nemesis. Long time no see. Go home. You're drunk.