Aug 19, 2020 02:55 AM
https://gizmodo.com/does-our-sun-have-a-...1844766242
EXCERPTS: The strange configuration of material in the outer reaches of our solar system has led a team of scientists to speculate that the Sun had a companion during its early days. Intriguingly, this scenario could explain the presence of the hypothesized Planet Nine, should it actually exist. Our Sun’s hypothetical twin is long gone, but traces of it can be seen in the overabundance of material located within the outer Oort Cloud, according to new research published in The Astrophysical Journal Letters.
[...] To date, computers trying to simulate the formation of the solar system have failed to reproduce the proportion of objects seen in the outer realms of the Oort cloud ... As a result, the origin of the outer Oort cloud is “an unsolved mystery,” according to the paper, authored by astronomers Avi Loeb and Amir Siraj from the Center for Astrophysics at Harvard & Smithsonian.
The new paper presents an elegant solution to the overpopulation problem: a second sun. “A stellar companion to the Sun would increase the chance of trapping objects from the birth cluster of the Sun,” wrote Loeb in an email. “The Sun and its companion act as a fishing net that traps objects gravitationally as they pass near one of the two stars and lose energy by kicking it slightly.”
By birth cluster, Loeb is referring to a cluster of stars that arose together in the same molecular cloud, also known as a stellar nursery. Star clusters eventually scatter, either because of strong stellar winds or tidal gravitational forces exerted by the Milky Way galaxy itself. The Sun’s hypothesized twin would have been pulled far, far away.
[...] The hypothesized second sun, in order to trap this excess material, would require a mass comparable to our own Sun. So, basically a twin. The two stars would would have been roughly 1,000 AU apart, according to the new model. “It is entirely plausible that the Sun could have started its life as a binary system,” Konstantin Batygin, a professor of planetary science at the California Institute of Technology who wasn’t involved in the new study, said in an email. “In fact, observations of young star clusters suggest that a very large fraction of sun-like stars are born as multiples, which later dissociate.”
Copious amounts of celestial material would have been lost when the two stars separated, but the authors contend that enough material remained to explain the Oort cloud. Passing stars in the birth cluster were likely responsible for separating the Sun from its presumed companion, but not before our solar system captured its outer population of objects... (MORE - details)
EXCERPTS: The strange configuration of material in the outer reaches of our solar system has led a team of scientists to speculate that the Sun had a companion during its early days. Intriguingly, this scenario could explain the presence of the hypothesized Planet Nine, should it actually exist. Our Sun’s hypothetical twin is long gone, but traces of it can be seen in the overabundance of material located within the outer Oort Cloud, according to new research published in The Astrophysical Journal Letters.
[...] To date, computers trying to simulate the formation of the solar system have failed to reproduce the proportion of objects seen in the outer realms of the Oort cloud ... As a result, the origin of the outer Oort cloud is “an unsolved mystery,” according to the paper, authored by astronomers Avi Loeb and Amir Siraj from the Center for Astrophysics at Harvard & Smithsonian.
The new paper presents an elegant solution to the overpopulation problem: a second sun. “A stellar companion to the Sun would increase the chance of trapping objects from the birth cluster of the Sun,” wrote Loeb in an email. “The Sun and its companion act as a fishing net that traps objects gravitationally as they pass near one of the two stars and lose energy by kicking it slightly.”
By birth cluster, Loeb is referring to a cluster of stars that arose together in the same molecular cloud, also known as a stellar nursery. Star clusters eventually scatter, either because of strong stellar winds or tidal gravitational forces exerted by the Milky Way galaxy itself. The Sun’s hypothesized twin would have been pulled far, far away.
[...] The hypothesized second sun, in order to trap this excess material, would require a mass comparable to our own Sun. So, basically a twin. The two stars would would have been roughly 1,000 AU apart, according to the new model. “It is entirely plausible that the Sun could have started its life as a binary system,” Konstantin Batygin, a professor of planetary science at the California Institute of Technology who wasn’t involved in the new study, said in an email. “In fact, observations of young star clusters suggest that a very large fraction of sun-like stars are born as multiples, which later dissociate.”
Copious amounts of celestial material would have been lost when the two stars separated, but the authors contend that enough material remained to explain the Oort cloud. Passing stars in the birth cluster were likely responsible for separating the Sun from its presumed companion, but not before our solar system captured its outer population of objects... (MORE - details)