In the hours before August 30, a Ukrainian amateur astronomer named Gennady Borisov spotted a strange comet approaching through our solar system. Astronomers have now provisionally verified that an object called C / 2019 Q4 (Borisov) is moving too fast to be captured by the gravity of the sun – a sign that it is most likely an interstellar interloper.
If we continue to hold these results, C / 2019 Q4 will be just the second visitor to another star system ever discovered after the 2017 discovery of the mysterious space rock known as "Oumuamua. Although its origin is not yet fully certain, C / 201
This means that scientists will be able to collect much more data about its composition than they would have been able to obtain for "Oumuamua. On the one hand, the C / 2019 Q4 is larger and brighter, offering more opportunities to study its light and extract chemical clues. What is more, astronomers have discovered "Oumaamawa is only exiting the solar system – but C / 2019 Q4 is still incoming. It will take its closest approach to the sun on December 7th and will come closest to Earth within 180 million miles on December 29th.
"This is the first highly active object we've seen coming from something that formed around another star," says Michelle Banister, an astronomer at Queen's Belfast University. Bannister adds that observations of the C / 2019 Q4 cannot be taken seriously until mid-October because of its position against the blinding sun. But then, for months, astronomers will turn their gaze to the sky to get their best view of an interstellar visitor.
"What's really fantastic is that this thing has to be monitored for a year," says Matthew Holman, interim director of the International Astronomical Union's Small Planet Center, which issued the Q / 2019 road test Q4 through space on Wednesday night.
"We'll see a little more from another solar system," he adds, "and without necessarily knowing which one it originated from, it's exciting. ”
Borisov, a comet-hunter veteran, found C / 2019 Q4 by focusing his observations at the Crimean Astrophysical Observatory on the low horizon to the northeast, in a piece of sky near the constellation Gemini. Astronomers tend to avoid peeking into those "bright" spots in the sky near the horizon, as they are difficult to see and can damage the sensitive optics of telescopes.
Early reports of Borisov's discovery made waves among astronomers. Quanji Ye from the University of Maryland first learned of the comet on Sunday after a colleague commented on the object's strange orbital recording in a group email. In addition, you notice that the Scout, a comet and asteroid tracking service operated by the NASA Jet Propulsion Laboratory, continued to calculate that the object had no orbital or elliptical orbit.
In particular, you are fascinated by one of the orbital parameters of a comet: its eccentricity. If the eccentricity of the orbit is zero, the object traces a perfect circle around its home star. The longer and narrower the orbit, the closer the eccentricity is to one. If an object in our solar system has an eccentricity greater than one, it means that the object has an arcuate trajectory and makes a one-time visit. The Small Planet Center says that the eccentricity of the C / 2019 Q4 exceeds three.
According to Ye, C / 2019 Q4 is unlikely to be a comet that formed at the edge of the solar system and was somehow squeezed into the escape path. To get this kind of shake, a comet must approach an object large enough to change its course, like a planet. But as far as astronomers know, C / 2019 Q4 couldn't come anywhere near such usurpers in our solar system. The orbits of planets around the sun align more or less in the same plane, but the C / 2019 Q4 appears to be bombarding the solar system at an angle of 44 degrees.
"That's why saying gravitational disturbance is almost impossible, says J.
Astronomers estimate that at any given time there is some interstellar comet or asteroid somewhere in the orbit of Mars and 10,000. or more in the orbit of Neptune, but these objects are small and extremely pale, making them almost impossible to see.
"Oumaamua, the first interstellar visitor discovered in our solar system, shook in the fall of 2017. Astronomers did not notice the strange object until it came out. of the solar system, shedding 98,000 miles per hour. But in the little time they had, impatient scientists around the world directed their telescopes at the object, and they learned a surprising amount about this piece of space debris. (Learn more about & # 39; Oumuamua and what made it so strange.)
While the distant object seemed only a pinch of light in the best telescopes, its intense darkening and illumination every few hours suggested that it was elongated ending near the end as it zips through our solar system. Astronomers estimate the object was anywhere between 590 feet to a quarter mile, but only up to 130 feet wide, giving the rocky body a pencil-like appearance.
Even more curious is that "Oumaamua did not continue to move at the same rate. After casting itself around the sun in early 2018, it suddenly jumped. Speculation immediately turned to the cause. Harvard professors Shmuel Biel and Abraham Loeb introduced another world idea: Maybe it was a spacecraft using a solar canvas sent from extraterrestrial civilization.
However, there is almost certainly a more secular explanation. According to other studies, the openings on the surface of the site could release jets of gas that give a boost at a burst of commercial activity too weak to see our telescopes. Or "Oumaamua could be a ball of porous screams, which was light enough for sunlight to incite him.
'Oumaamua has left many puzzles that can never be solved, which is why the prospect of studying C / 2019 Q4 in astounding detail astounds astronomers. When asked by e-mail what he did to check the Center for the Small Planets, you replied: "Yeaaaaaaaaaah time to get telescopes !!!"
Maya Wei-Haas presented a report.