Findings of a new study have shown that the first comet identified to visit the Sun after its birth around an alien star may be the most pristine comet ever discovered.
The New Atlas reported that this study sheds light on the distant solar system in which the traveling body, now identified as 2I/Borisov, formed before it casts out into the lowest points of interstellar space.
Comets are vitally ancient chunks of waste material left over from the planetary formation phase of the solar system.
They are said to be highly prized aims for astronomers who are seeking to understand the solar system's early history as they provide an opportunity to assess the ancient material from which everything in the cosmic neighborhood's little corner coalesced.
Nonetheless, just because they are comparatively well preserved, it does not mean that they are perfectly preserved.
For quite a very long time, stellar wind, as well as radiation take their toll on wondering comets that pass near a star, stimulating changes in their outer layers.
'Extrasolar Nature' of Comet
In 2019, Gennady Borisov, an astronomer, discovered a new wondering body akin to a comet that upon further assessment, seemed to have originated from outside of the solar system.
The extrasolar nature of a comet was later verified by the International Astronomical Union, conferring upon it 2I/Borisov as the name.
What was described in the study as unexpected visitor was just the second object, following rocky oddball 'Oumuamua' in 2017, known to have visited the Sun following its birth in the orbit of another star.
This made it such a tantalizing target for astronomers who observed in 2I/Borisov an exceptionally rare opportunity to collect understandings into the prehistoric cloud of gas and dust from which it was born.
The new research entitled "Unusual polarimetric properties for interstellar comet 2I/Borisov," published in Nature Communications, specified that this wandering chunk of space debris may exemplify the most pristine comet ever discovered, which in turn, may specify that it has never passed near a stellar body.'
The 'Polarimetry Technique'
Researchers of this new work saw 2I/Borisov through polarimetry technique that uses the FORS2 instrument positioned on ESO's Very Large Telescope in Chile.
In this circumstance, polarimetry enabled the astronomers to gauge the light's polarization from the Sun as it passed through the dusty coma of the interstellar visitor.
2I/Borisov was discovered to be photometrically distinctive from the vast majority of solar system comets and boasted higher light polarization levels compared to its earthly counterparts.
Only a single solar system wanderer was discovered to have the same polarimetric properties as 2I/Borisov, the popular "Hale-Bopp' comet.
In 1997, this popular comet passed near the Sun, and for a while, it became a remarkable sight in the evening sky.
For astronomers, that Hale-Bopp had only passed the Sun once in its long-time history before 1997. Nevertheless, the polarimetric data from 2I/Borisov discloses that, unlike the said famous comet, it is playing host to what's described as a polarimetrically homogeneous coma.
2I/Borisov More Pristine Than Hale-Bopp
The study investigators said that this dust and gas's comparatively uniform coma specifies that 2I/Borisov is even more pristine compared to the Hale-Bopp. This led them to propose that the alien comet may never have passed near a stellar body.
These otherwise similar polarimetric properties to Hale-Bopp also specify that 2I/Borisov merged from a primordial cloud the same as that form which the solar system formed.
Separate research entitled Compact pebbles and the evolution of volatiles in the interstellar comet 2I/Borisov, that came out in the Nature Astronomy journal has shown further evidence that the home star system of 2I/Borisov is similar to the Earth's own.
This second study concentrates on the carbon monoxide levels, as well as the particles that exist in the comet's coma, not to mention the manner that the amounts of these particles differed as it moved toward the Sun. It took into account too, the grains' presence, roughly a millimeter across, or even larger.
The team behind the Natural Astronomy paper said such characteristics propose that 2I/Borisov formed from objects that were created various parts of a distant solar system.
Related information about polarimetry is shown on The Audiopedia's YouTube video below:
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