Our Sun may have once had twins, astronomers have suggested – like the ‘binary’ stars of Tattooine in Star Wars.
Harvard researchers said another sun was present when the solar system formed, and it could explain features, including a cloud of punctures at the edge of our solar system.
The finding could shed light on events such as the arrival of water on our planet and even the extinction of dinosaurs, the researchers believe.
It could also fill in the blanks about Planet Nine, the hypothetical body that scientists think they could draw on the edge of our solar system.
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Scientists believe that the Oort cloud was formed from debris left over from the formation of the solar system and its neighbors, where objects were scattered across large planets and large ones were exchanged between stars.
But once the sun had a binary “twin,” it would be easier to understand how the cloud formed, said Harvard undergraduate student Amir Siraj, one of the study’s authors.
He said: “Previous models have struggled to produce the expected ratio between scattered disk objects and outer Oort cloud objects.
“The binary capture model offers significant improvement and refinement, which is evident in retrospect: most Sun-like stars are born with binary companions.”
Understanding the formation of the Oort cloud could provide scientists with important insights into the history of life on Earth, the researchers said.
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“Objects in the outer Oort cloud may have played important roles in the history of the earth, such as possibly supplying water to the earth and causing the extinction of the dinosaurs,” Siraj said.
“Beginning of their origin is important.”
Binary stars are better at drawing and capturing debris (like the material that made up the Oort cloud), according to Hari’s Avi Loeb.
Loeb said, “If the Oort cloud formed as observed, it would imply that the sun actually had a companion of the same mass that was lost before the sun left its birth cluster.”
The researchers said the binary star would have disappeared in the early history of the solar system, and now could be almost anywhere.
Siraj said: “The long lost companion of the sun could now be anywhere in the Milky Way.
“Before the loss of the binary, however, the solar system would have captured all of its outer envelope of objects, namely the Oort cloud and the population of the Planet Nine.”
