MADRID, 18 Ago. (EUROPA PRESS) –
A new theory published in Astrophysical Journal Letters by scientists at Harvard University suggests that the sun may have once had a binary companion of similar mass.
If confirmed, the presence of an early stellar companion explains the observed scattering of the Oort cloud at the edge of the system and increases the probability that the supposed Planet Nine was captured rather than formed within the solar system.
Dr. Avi Loeb, professor of Astronomy at Harvard, and Amir Siraj, a student at the university, have postulated that the existence of a long-lost stellar binary companion in the sun’s birth cluster: the collection of stars that formed together with the sun from the same dense cloud of molecular gas, could explain the formation of the Oort cloud as we observe it today.
Popular theory associates the formation of the Oort cloud with the remnants of the formation of the solar system and its neighbors, where objects were scattered across planets at great distances and some were exchanged between stars. But a binary model could be the missing piece to the puzzle, and according to Siraj, it shouldn’t surprise scientists.
“Previous models have struggled to produce the expected relationship between scattered disk objects and external objects in the Oort cloud. The binary capture model offers significant improvement and refinement, which seems obvious in hindsight: most of stars similar to the sun are born with binary partners, “he explains it’s a statement.
If the Oort cloud were actually captured with the help of an early stellar companion, the implications for our understanding of the formation of the solar system would be significant. “Binary systems are much more efficient at capturing objects than individual stars,” Loeb said. “If the Oort cloud formed as observed, it would imply that the sun did indeed have a companion of similar mass that was lost before the sun left its birth cluster. “
More than simply redefining the formation of our solar system, evidence from a captured Oort cloud could answer questions about the origins of life on Earth. “Objects in the outer Oort cloud may have played an important role in Earth’s history, like possibly bringing water to Earth and causing the extinction of the dinosaurs, “said Siraj.” It is important to understand their origins. “
The model also has implications for the supposed Planet Nine, which Loeb and Siraj believe is not alone there. “The enigma is not only about the Oort clouds, but also extreme trans-Neptunian objects, like the potential Planet Nine,” Loeb said. “It is not clear where they came from, and our new model predicts that there should be more objects with an orbital orientation similar to Planet Nine.”
Both the Oort cloud and the proposed location of Planet Nine are so far from the sun that direct observation and evaluation are a challenge for researchers today. But the Vera C. Rubin Observatory (VRO), which sees first light in early 2021, will confirm or deny the existence of Planet Nine and its origins.
Siraj is optimistic: “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 lonely stellar history that has long been assumed. weather”.
If the sun had an early companion who contributed to the formation of the outer solar system, its current absence raises the question: where did it go? “The passage of stars in the birth cluster would have moved the companion away from the sun through its gravitational influence”Loeb said.
“Before the loss of the binary, however, the solar system would have already captured its outer envelope of objects, namely the Oort cloud and Planet Nine.” Siraj added: “The lost companion of the sun could now be anywhere in the Milky Way.”
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