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Sun's long-lost twin could have captured Planet Nine

Sun's long-lost twin could hav...
The Sun may once have had a twin that was later lost
The Sun may once have had a twin that was later lost
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The Sun may once have had a twin that was later lost
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The Sun may once have had a twin that was later lost

While the Sun is very clearly a solo act nowadays, some astronomers theorize that it once had a binary companion star. Now, Harvard scientists have added weight to the idea by showing that an ancient binary solar system explains the strange structure of the Oort cloud, and possibly the hypothetical Planet Nine. Best of all, the team outlines how we could check.

The Sun was born about 4.6 billion years ago in a gigantic cloud of dust and gas. But it almost certainly wasn’t alone – if other stellar nurseries are anything to go by, then countless other baby stars would have formed around the same time. Most of them would have drifted away soon after, spreading through the galaxy.

But some scientists believe there’s evidence that the Sun had a twin long after it left the nest. Previous work has shown that many Sun-like stars are born with companions, forming binary pairs. Over a few million years or so, most drift apart to form single-star systems, while others move closer and become tighter-knit binaries. If the Sun was once half of a binary pair, it would obviously belong to the first group.

It’s an interesting story, but what evidence is there to support it? In the new study, the Harvard researchers suggest that the smoking gun may lie on the outskirts of the solar system.

The Oort cloud is a huge ball of icy objects that surrounds the solar system at an estimated distance of between 2,000 and 100,000 Astronomical Units (AU) from the Sun. For reference, the Earth is 1 AU from the Sun, and even Pluto usually orbits at a distance of only 40 AU.

Exactly how such a cloud of objects formed so far away remains a mystery. Current thinking goes that they’re leftover crumbs from the formation of the solar system’s planets and moons, much like the asteroid belt. But that story has a few holes in it.

Instead, the team’s new hypothesis posits that Oort cloud objects were more likely passersby that were captured by the gravity of two Suns.

"Previous models have had difficulty producing the expected ratio between scattered disk objects and outer Oort cloud objects,” says Amir Siraj, co-author of the study. “The binary capture model offers significant improvement and refinement, which is seemingly obvious in retrospect: most Sun-like stars are born with binary companions.”

Interestingly, the new model also has implications for Planet Nine, a hypothetical world thought to be lurking in the dark on the fringes of the solar system. According to the team, the gravity of binary stars would have captured an abundance of dwarf planets, including potentially a larger one like Planet Nine.

That gives astronomers a way to test the theory. Our catalog of distant dwarf planets is regularly growing with the addition of strange worlds like Farout and the Goblin, and more observations could help confirm the idea. And the Vera Rubin Observatory (VRO), due to start the hunt in early 2021, could be a good start.

"If the VRO verifies the existence of Planet Nine, and a captured origin, and also finds a population of similarly captured dwarf planets, then the binary model will be favored over the lone stellar history that has been long-assumed,” says Siraj.

So where is this second Sun now? The team says that it was most likely jostled away by the gravity of other stars in the birth cluster.

"Before the loss of the binary, however, the solar system already would have captured its outer envelope of objects, namely the Oort cloud and the Planet Nine population." says Siraj. "The sun's long-lost companion could now be anywhere in the Milky Way.”

The research was published in The Astrophysical Journal Letters.

Source: Harvard-Smithsonian Center for Astrophysics

8 comments
Worzel
Maybe, it was our sun and its satellite system, that 'drifted away'.
The sun orbits the Galaxy, independently from the rotation of the galaxy, and it follows a sinusoidal path through the plane of the galaxy.
This would suggest that it was flying through space, and was captured by the galaxy, while the binary companion, if there was one continued on its original or alternative pathway.
wolf0579
Goddamn idiots are all around and you can't shoot them.

You speak about this mythical "Planet Nine" as if it were a real thing.

Shouldn't you PROVE the existence of the thing before you refer to it as if it were real?
Pmeon
@ Wolf0579, too funny.
Astronomy is 99% fiction. Can't solve a problem, no worries consult the MSU book.
For instance, the sun is a big cloud of hydrogen gas and black holes come from neutron stars but lone neutrons have a half life of 14 minutes and the big bang theory was invented by a Catholic priest to appease the creation story and the black dark matter stuff has never and will never be proven or found. A large meteorite selectively wiped out the dinosaurs but not the mammals and some humans evolved from monkeys. So yeah planet 9 nine fantasy story, why not. Everything else is a joke.
Karmudjun
OMG LOL!!!!
wolf0579 - Pmeon - you guys should go on the road!

Scientists believe in explanations, and even if their explanation is proved false, it is considered an important finding along the way to truth.....absolute truth, a truth that is immutable and cannot be proven false. Scientists - at least good scientists - may feel they are absolutely right, but they publish in peer reviewed journals so that people slightly smarter or slightly dumber may poke legitimate holes in their theories.

You too are just blathering for the sake of your own ego. I see no primary research in your statements that cannot be flailed for falsehood and incorrect supposition from the first: Example....Wolf's first statement....of course you can't shoot them, you'd break the mirror. Pmean, I can't wipe the tears away from all my laughter to start addressing your statements - OMG they are so far off the mark as to be utterered by a 7 year old.....keep it fresh man - you have a career in comedy!
Mark Bowyer
@Pmeon
Your claim that humans "evolved from monkeys" shows you don't really understand evolution. We had a common ancestor long, long ago. One line eventually led to monkeys, another led to the humans and the other Great Apes (and other species of human than are no longer with us)
meofbillions
@Pmeon And congratulations, you're the funniest joke.
Pmeon
@Karmudjun, "see no primary research in my statements", try these. Half life of a lone Neutron. https://www.quantamagazine.org/neutron-lifetime-puzzle-deepens-but-no-dark-matter-seen-20180213/
Notice I did say "some" humans evolved from monkeys. Precision matters.
The inventor of the big bang. https://www.amnh.org/learn-teach/curriculum-collections/cosmic-horizons-book/georges-lemaitre-big-bang
Watch this video and try and explain it in terms of a gas. https://www.youtube.com/watch?v=HFT7ATLQQx8
The gas sun theory does not comply with the laws of thermodynamics, try doing the calculations yourself.



ljaques
wolf0579 - Pmeon - you guys should know that it's turtles all the way down. // Car 54, Where Are You? You are needed to locate a mysterious Planet Nine. Over.