https://www.sciencealert.com/our-new-interstellar-visitor-is-now-official-and-it-has-a-name
The verdict is in: after a thorough round of observations, the comet suspected of being an interstellar alien has been ratified. According to the International Astronomical Union (IAU), the comet is "unambiguously" interstellar in origin, and it has now been given a name: 2I/Borisov.
Previously, the comet had been going by the provisional name C/2019 Q4 (Borisov). C means it's a comet with a hyperbolic orbit, followed by the year it was discovered, an alphanumeric code for when in the year it was discovered, and the comet name in parentheses - that's Crimean amateur astronomer Gennadiy Borisov, who spotted the comet with telescope he made himself.
The new name has been simplified. In 2I, I stands for "interstellar", and 2 for being the second interstellar object ever discovered, after 'Oumuamua, which was detected in October 2017.
Previously: Possible Second Interstellar Object Discovered
Related Stories
https://www.skyandtelescope.com/astronomy-news/possible-interstellar-comet-headed-our-way/
First there was 'Oumuamua, discovered nearly two years ago. Now we might be in store for another interstellar flyby, this time by the recently discovered comet known for now by the provisional designation C/2019 Q4 (Borisov) — formerly gb00234. Gennady Borisov captured the object on August 30, 2019, at the Crimean Astrophysical Observatory when it was about 3 astronomical units (a.u.) from the Sun. Unlike 'Oumuamua, which wasn't spotted until well after perihelion, the new comet is approaching the plane of the solar system and will reach perihelion on December 10, 2019.
[...] If this result holds up, astronomers have an unprecedented opportunity to study a potentially interstellar object in great detail over a long span of time. Based on the comet's current magnitude (~18) and distance from the Sun (2.7 a.u.), it appears to be a fairly large object — perhaps 10 km or more across, depending on the reflectivity of its surface.
[...] For predicted positions and current orbital element, check out the Minor Planet Center's latest circular MPEC 2019-R106.
From the link at the Minor Planet Center:
Based on the available observations, the orbit solution for this object has converged to the hyperbolic elements shown below, which would indicate an interstellar origin. A number of other orbit computers have reached similar conclusions, initially D. Farnocchia (JPL), W. Gray, and D. Tholen (UoH). Further observations are clearly very desirable, as all currently-available observations have been obtained at small solar elongations and low elevations. Absent an unexpected fading or disintegration, this object should be observable for at least a year.
In other words, further observations are needed to better determine its exact path as it approaches the Sun.
(Score: 2) by FatPhil on Thursday September 26 2019, @09:34AM (5 children)
Did the object come from the direction of the outer Opik-Oort[*] Cloud? Well, considering it's a s sphere - that would be a yes.
Did Gran Telescopio Canarias in the Canary Islands obtained a spectrum of 2I/Borisov and has find it to resemble those of typical cometary nuclei? Strange you should ask that, because it unambiguously did.
So it looks like something from the Opik-Oort Cloud, and it came from the direction of the outer Opik-Oort Cloud.
If it had crashed into Mars, then it would have completely satisfied one of the timelines of Objects in the Opik-Oort Cloud - they smash into sol or a planet, or they get scattered into space. By missing Mars, it's satisfied the second of those options - it's being scattered after a Solar/Martian flyby. All it needed was some kind of perturbation from a regular (elliptical) cometary orbit tens of thousands of years ago, last time it was near apehelion - you know, your typical gravitational slingshot for changing orbits. It's still following one of the many solar-system-object scripts, albeit a very rare one. What was that, you say this is a very rare occurrance?
Can the IAU put their hands on their hearts and say unequivocally that such an encounter is absolutely impossible?
[* Fuck Oort, he got there decades after the Estonian, I'm almost tempted to drop his name entirely, and just call it the Opik[**] cloud!]
[** And fuck Estonia if they demand I put diacriticals on letters - ASCII forever! (But I forgive them for mispronouncing my name, 'Ph' is a retarded digraph, 'F' makes way more sense.)]
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: -1, Offtopic) by Anonymous Coward on Thursday September 26 2019, @10:31AM
[*** Also, fuck Gennadiy, this is obviously named after Borisov Johnson]
(Score: 4, Interesting) by Anonymous Coward on Thursday September 26 2019, @06:02PM (2 children)
The orbit is unambiguously hyperbolic. Comets from the Oort cloud have an eccentricity of nearly 1. These are nearly parabolic, as would be expected for objects that are almost, but not quite, coming from outside the Sun's sphere of influence. A few have eccentricities slightly over 1. Depending on what happens to them on the way back out, some of those will leave the Solar system.
Borisov isn't like that. It has an eccentricity of 3.5. It's not anywhere close to an Oort cloud object. Nor is there any form of gravitational perturbation that could have created such an orbit. It simply has far too much energy to have received it from gravity. Its "orbit" is actually not extremely different from the Voyager spacecraft, which took powerful rockets and multiple gravity assists from giant planets to reach their velocities.
It's just not from the Oort cloud. So the fact that it has chemistry that resembles local comets tells us that the comets of other stars aren't necessarily that different from ours. But hopefully they'll spot some interesting differences too.
(Score: 0) by Anonymous Coward on Thursday September 26 2019, @06:21PM
Closest approach in December at around 1.9 AU.
(Score: 2) by FatPhil on Friday September 27 2019, @10:58AM
It has an eccentricity of 3.5 because that's how it's being ejected from the solar system.
Reread my post, this time for comprehension. Avoid the footnotes, they clearly confused you last time.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by PartTimeZombie on Thursday September 26 2019, @10:11PM
Goodness! I never knew there was that much passion amongst the
astrologyastronomy crowd.Apart from that whole Pluto thing a few years ago, of course.
(Score: 1) by oumuamua on Thursday September 26 2019, @12:23PM
I told her to make that left turn at Eta Cassiopeiae, now she is going to miss the Tesla intercept! Women drivers, what can you say.
https://www.whereisroadster.com/ [whereisroadster.com]
(Score: 0) by Anonymous Coward on Thursday September 26 2019, @06:26PM (2 children)
https://en.wikipedia.org/wiki/2I/Borisov [wikipedia.org]
(Score: 0) by Anonymous Coward on Thursday September 26 2019, @09:49PM (1 child)
Isn’t Juno out there? Seems like it could take a quick look.
https://en.m.wikipedia.org/wiki/Juno_(spacecraft)#Planned_deorbit_and_disintegration [wikipedia.org]
Also, a good reason to leave these missions running long term - just to catch special opportunities like this
(Score: 1, Interesting) by Anonymous Coward on Thursday September 26 2019, @09:57PM
If you want to intercept an interstellar object to capture it or prevent it from hitting Earth, you would need very sensitive telescopes that could image it years in advance, so you could launch a mission years in advance.
ESA's upcoming comet mission will be launched with no target in mind: https://soylentnews.org/article.pl?sid=19/06/22/1811224 [soylentnews.org]
If the solar system was filled up with spacecraft like that, more transient events could be discovered at the very least.