In the summer of 2019, an unknown object from an unknown star entered our solar system. It was the first interstellar comet ever seen. Nobody knows what it’s made of or how long it’s gone through space. On Earth, Gennady Borisov, an amateur astronomer from Ukraine, was the first to see it, and he named it 2I / Borisov in his honor.
Until then, only one object from another solar system had been known: the asteroid Oumuamua, whose strange shape has led to speculation since its observation in 2017. “Interstellar comet? Cosmic iceberg? Space debris?” Requested Die New York TimesThe latest theory is that it ripped off somewhere far away from a Pluto-like planet.
These rare objects are exciting, like a time capsule that contains information about other inaccessible stars Manned spacecraftAnd maybe over the planet around them. The sun and the planets around it, including the Earth, are moving across the Milky Way galaxy at a speed of 220 kilometers per second. During this journey, it is possible that we will be so close to another solar system that a comet or asteroid is absorbed into the sun’s gravitational field or in the orbit of giant planets such as Jupiter or Saturn. These visitors can either stay stuck in their new home forever or walk through it and return to interstellar space.
Researchers speculate that there may have been gas giants in this solar system that attracted the comet by the force of gravity
So astronomers think Oumuamua and 2i / Borissov have arrived, and it is tempting to think about whether space travelers like these could transport vital elements from one star to another and even to other planets for seed. This week, two teams of astronomers presented results from Borisov’s observations of two of the most powerful telescopes on Earth.
The first team tried to understand when this comet formed and how its long journey through space affected it. Astronomers focused on Borissov using the Very Large Telescope, a telescope facility operated by the European Southern Observatory in the Chilean Atacama Desert. Compare the observations with those of other known comets. It only resembles Hale-Bopp, a comet that was discovered in 1995 and was so bright that it could be seen with the naked eye in the night sky for 18 months. The results of the first study were published this week Connect with natureIt indicates that Borisov is safer.
“It is likely that Comet 2I / Borisov never passed near the Sun or any other star, and it could represent the first truly pure comet ever observed,” the study authors wrote. Purity means old, so it is possible that the raw material is dust and gas, and it is very similar to the material that was around the sun shortly after its birth about 4.5 billion years ago, before the planets of our solar system existed. Researchers believe that since its inception, Borisov has not come close enough to a star to decay.
The second study published by the journal NaturastronometryIt demonstrates that the comet is composed of particles and pebbles of various sizes. Ben Yang, an astronomer at the European Southern Observatory, analyzed Borissov using the Atacama Large Millimeter / Sub-Millimeter Array (ALMA), which is currently the largest radio telescope in the world. Their results indicate that the comet is a mixture of materials from different parts of the Solar System from which it originated.
Researchers speculate that there may have been gas giants in this solar system that attracted the comet with their gravity. Borissov is currently located 10 astronomical units, or about 1.4 billion kilometers, from Earth, explains Luisa Lara, a researcher at the Andalusian Institute of Astrophysics. “It will continue to move away from us and leave our solar system in about 15,000 years,” she said. Lara was part of the science team for the Rosetta mission, a European space probe sent to probe comet 67P / Churyumov-Gerasimenko. He found that oxygen and organic matter were vital to the origin of life on Earth.
The Astrophysicist People often report that the basic components of life came to Earth from space, possibly in the appearance of comets. Glycine, an amino acid that may be one of the first building blocks for living molecules such as RNA, has been found on comets. In her opinion, the two studies published this week are in line with what a comet expects because although it formed in another solar system, it is consistent with studies in our solar system.