Talk:2I/Borisov

Size?

Using H=12.5, and albedo between 5%-20%, a full phase diameter estimate comes out as 8 to 20 km, small, but much larger than Oumuamua. Tom Ruen (talk) 01:07, 11 September 2019 (UTC)

But the object has been confirmed to be a comet so you can not use the asteroid scale. There is good chance the nucleus is less than 5km in diameter. -- Kheider (talk) 01:12, 11 September 2019 (UTC)

The albedo can only be assumed to be 5-20% for asteroids, it doesn't work for comets. There is no direct link between absolute magnitude and size for comets. This object doesn't appear to be extremely active right now, but I don't think 20 km is an option. Karen Meech estimated it to be between 2 and 16 km in diameter. I'd be surprised if the higher limit holds, but the lower limit sounds perfectly realistic. Note that it corresponds to an albedo of 450%, which is perfectly fine for comets (we mostly see light reflected from the coma, not the nucleus). This object is much larger than anyone would expect to see for an interstellar interloper. Renerpho (talk) 00:11, 13 September 2019 (UTC)

JPL orbit

JPL small body database browser has e=3.52161 +/- 0.19684, a=-0.817754 +/- 0.045762, I calculate v infinity as 32.9 km/s using the latter. Agmartin (talk) 22:41, 11 September 2019 (UTC)

I can confirm your calculation. JPL's value is different from that given by the MPC mostly because JPL uses a different weighting scheme. Bill Gray, using the same model as JPL, got an eccentricity of about 3.5, too, and about 3.1 without weightings. The difference between these is hard to see with so little data, we have to wait a few weeks to pin it down. v_inf is certainly around 30-35 km/s.

Distance detected?

Roughly how far away was this object when it was first detected? And, why didn't PanStarrs find it? --213.233.88.147 (talk) 13:23, 12 September 2019 (UTC)

2019 Q4 was 3.75±0.13 au from Earth on 30 August 2019. It was not detected by Pan-STARRS because the Solar elongation has been less than 45 degrees since early May 2019. -- Kheider (talk) 14:06, 12 September 2019 (UTC)

Is it worth mentioning the comet will cross the solar system plain somewhere between Mars and Jupiter? I think it gives an idea (in addition of the au) to the closest it will get to the Sun. Cheers, Rowan Forest (talk) 13:17, 13 September 2019 (UTC)

Gennady Borisov

Some news accounts call Gennady Borisov an amateur astronomer, but that is not true, correct? What is his position? Abductive (reasoning) 22:29, 12 September 2019 (UTC)

As I understand it, he is an experienced amateur and that is why he discovered the comet. Professional surveys normally do not look within 45 degrees of the Sun because of the size of the telescope and dome limitations. -- Kheider (talk) 23:17, 12 September 2019 (UTC)

He is an amateur astronomer. The thing that makes him an amateur is that he is not paid for his work (this does not account for research grants, which are often given to amateurs). It does say absolutely nothing about the quality of his work, or about the scope of discoveries he could make. Renerpho (talk) 00:16, 13 September 2019 (UTC)

Gennady V. Borisov is a 1st category engineer working at the Department of Physics of Emissive Stars and Galaxies at the Crimean Astronomical Station of the State Astronomical Institute named after P. K. Shternberg of the Moscow State University named after M. V. Lomonosov (or CAS MSU for short). Source: http://www.sai.msu.ru/dept/crimea/index.html. --46.242.12.78 (talk) 01:17, 13 September 2019 (UTC)

NB: The English version of the website seems outdated. Use the Russian version with Google Translate. --46.242.12.78 (talk) 01:17, 13 September 2019 (UTC)

Also note that the Crimean Astronomical Station is located right next to the Crimean Astrophysical Observatory, but is not a part of it. The Crimean Astronomical Station's land and property is owned and run by the Moscow State University, while the Crimean Astrophysical Observatory's land and property is owned and run by the Federal Agency for Scientific Organizations. I don't know where Borisov's telescope was installed, but if it was installed at the Crimean Astronomical Station, then it would be incorrect to say that the extrasolar comet was "discovered at CrAO". I think it's best to ask Borisov himself whether he considers his discovery to be a part of his work at CAS, a part of his (possible) work at CrAO, or his own personal discovery made in his spare time. --46.242.12.78 (talk) 01:42, 13 September 2019 (UTC)

To be exact, working on telescopes is his job, although I can’t find the page where I read that now :( So you’d think he’s a hobbyist at watching the skies, but then in this NASA article, they say he discovered the object at MARGO observatory in Nauchnij, Crimea: https://www.nasa.gov/feature/jpl/newly-discovered-comet-is-likely-interstellar-visitor

However, I can’t find any information online about what that MARGO observatory might be. The name could be from a Russian acronym, because the first two letters fit with "International Astronomical …", but a search for "марго обсерватория" on the web doesn’t produce anything except articles about this new discovery. However, it is included as L51 on Wikipedia’s list of observatory codes, so it may just be a real observatory after all… https://en.wikipedia.org/wiki/List_of_observatory_codes#L00-L99

This isn’t really the place for discussing this, but I still find it strange that Nauchny (Wikipedia spelling) has no English article, although there are articles in German, French, etc. So the Crimean Astrophysical Observatory, which is located in Nauchny does have its page, but the (tiny) town doesn’t. It was built after WW II, around the telescopes, as a place for staff and their families to live.--Geke (talk) 15:22, 21 September 2019 (UTC)

MARGO is the name of Borisov's private observatory, i.e. his two GENON Max telescopes and the new, still unnamed, 0.6-meter telescope, all of which are situated on a patch of land right next to a small building housing SAI's ZEISS-600 telescope which Borisov services as his day job (but does not use as an astronomer). Unfortunately, there is no direct quote on this. We know this because NASA says C/2019 Q4 was discovered at MARGO observatory, and we know C/2019 Q4 was discovered by Borisov using his own custom-built 0.6-meter telescope, so putting two and two together, it is clear that Borisov calls his telescopes "MARGO observatory". Hopefully, some English-language media outlet interviews him and asks a direct question about "MARGO" (and what the acronym means), so we can have an explicit answer. I agree with you that Nauchnyy should have its own page. — UnladenSwallow (talk) 23:36, 22 September 2019 (UTC)

MARGO is just the name given by Borisov to his private observatory. You can find it referred to in the discovery MPEC, and of course in the official list of Observatory Codes. The rules for how observatories are named are very lose, compare here. As for when the observatory was named - that happened on 17 November 2013, with the official announcement on the first page of this document. When you name your observatory (and I have done this a couple of times myself), you simply state what you want it to be called. You are not required to give an explanation, and the name can be completely meaningless, as long as it is unoffensive. Maybe Borisov explains the name at some point. If so, great. If not, I wouldn't worry about it too much. It's just a name. Renerpho (talk) 05:37, 23 September 2019 (UTC)

2I/Borisov

Until the MPC makes an official announcement we should not title it as 2I/Borisov. JPL has no link to 2I. -- Kheider (talk) 14:58, 13 September 2019 (UTC)

@Kheider: Yes - *entirely* agree - there is no official designation of "C/2019 Q4 (Borisov)" as "2I/Borisov" at the moment afaik - however - the comet seems to be "also known as '2I/Borisov'" (unofficially) by some - there may be more - hope this helps - in any case - Enjoy! :) Drbogdan (talk) 15:32, 13 September 2019 (UTC)

References

Wikipedia should not encourage the use of that name until it is official, and as an interstellar object it might get a more exotic name. -- Kheider (talk)

Thanks for your reply - yes - agreed - no problem whatsoever - Thanks again - and - Enjoy! :) Drbogdan (talk) 16:02, 13 September 2019 (UTC)

"Reachability" section

I rendered that section invisible as it looks not right to me. The object was just discovered, so it is unlikely a spacecraft was to be launched last year to intercept it.

In a related matter, there is Europe's Comet Interceptor to intercept an appropriate long period comet, and in case it doesn't find one, it could go after an interstellar object. But one needs references relating both, otherwise it is synthesis. Rowan Forest (talk) 22:26, 13 September 2019 (UTC)

A separate article on Gennadiy Borisov

An interview with Borisov with lots of interesting details: https://www.fontanka.ru/2019/09/13/052/. Machine translation is surprisingly readable, except for a few mistakes (him → it, sit → land, lovers/fans → amateurs, removed → captured). He has already discovered 7 comets since 2013 (for which he received three Edgar Wilson Awards), so this one is his 8th. In 2016 he was the only amateur astronomer in the world who managed to discover a comet. His previous discoveries were also made using his own custom-built telescopes: "small Genon" (2 discoveries) and "large Genon" (5 discoveries). He works as an engineer at the Crimean Observatory of the Sternberg Astronomical Institute of the Moscow State University. There he helps with the telescopes, but does not make observations himself. He also works for Astronomicheskiy Nauchnyy Tsentr, where he creates experimental telescopes in cooperation with Roscosmos. His discoveries are his own hobby. He thinks that soon amateurs will no longer be able to discover new comets: "In 2016, only I discovered a comet. In 2013, there were seven of us. Every year less and less. There are more and more huge telescopes. Amateurs will soon have nothing left."

I think that as this is his 8th comet (for which he will surely receive another Edgar Wilson Award, becoming a four-time winner) and the first interstellar comet ever discovered, Borisov deserves a separate article, even though he's an amateur astronomer. What do you think? If you agree, I'll create an article on him. — UnladenSwallow (talk) 14:18, 16 September 2019 (UTC)

• Support - Yes - agree that an article about Gennadiy Borisov seems indicated - afaik, Borisov seems sufficiently notable according to WP:PERSON guidelines - hope this helps - in any case - Enjoy! :) Drbogdan (talk) 15:00, 16 September 2019 (UTC)
• Support - he is notable by the discoveries he has done, amateur or not. Rowan Forest (talk) 17:42, 16 September 2019 (UTC)

I started the article on Gennadiy Borisov as a result of the discussion here. Editors may wish to know that it has been nominated for deletion. If interested, the discussion can be found at Wikipedia:Articles for deletion/Gennadiy Borisov Hallucegenia (talk) 21:10, 18 September 2019 (UTC)

• Support - as per the above. There should be enough material about him by now. Much of the material is in Russian, but Google and Youtube should help to translate. Material on his earlier discoveries can be found here and here. Renerpho (talk) 11:18, 19 September 2019 (UTC)
• Support – Strange that he doesn't have a page on Russian wikipedia. Should be at ru:Геннадий Борисов. — JFG ^talk 12:07, 19 September 2019 (UTC)

Inbound velocity when 3au from the Sun

Inbound velocity
when 3 au from the Sun
(wrt Sun)

Object	Velocity @ 3 au
C/2010 X1 (Elenin) (Oort cloud comet)	24.3 km/s 2011-Mar-22
1I/2017 U1 (ʻOumuamua)	35.9 km/s 2017-May-11
C/2019 Q4 (Borisov)	40.4 km/s 2019-Aug-29

Generated with JPL Horizons Observer Location: @sun and Table Settings: 22 Speed wrt Sun (VmagSn)

I wanted to put this table somewhere and did not want to risk cluttering up the main article for casual readers. -- Kheider (talk) 01:23, 17 September 2019 (UTC)

From a recent article on arXiv: "The orbit of C/2019 Q4 implies an excess heliocentric velocity of ∼ 31 km s−1. The heliocentric incoming velocity at infinity of the meteor in right-handed Galactic coordinates is v∞(U, V,W) ≈ (21, −23, 1) km s−1, which is ∼ 35 km s−1 away from the velocity of the Local Standard of Rest (LSR)" Agmartin (talk) 15:25, 17 September 2019 (UTC)

$v_{\infty }$ will be less than velocities that are closer to the Sun as the Sun will "pull the object inwards". At perihelion (2au) the comet will be doing 43.9 km/s wrt the Sun.

During 2019, the velocity wrt Earth varies from 24.8 km/s in mid-February to 65.6 km/s in early September.

Developing story

This comet is being closely watched, and the article might be subject to frequent updates. Is there a standard tag for fast-moving stories, and should this be headed with one? JDAWiseman (talk) 10:54, 19 September 2019 (UTC)

There is a {{current event}} notice, but that should only be used for really fast-moving developments receiving widespread and hourly coverage. Perhaps as the object approaches and becomes more visible that will be the case, but not now. — JFG ^talk 12:10, 19 September 2019 (UTC)

Should I include biographical information taken from a blog?

Renerpho has found a 2014 interview with Borisov with important biographical information (age, place of birth, alma mater, etc.): https://crimeanblog.blogspot.com/2014/09/borisov.html. It's posted on a blog, but it says it's a copy of an article from Russkaya planeta (Template:Lang-ru). Unfortunately, Russkaya planeta does not seem to have the article on its website, rusplt.ru. This is probably because Russkaya planeta changed ownership, and most of its staff left in December 2014.

So what should I do? Should I include this information or not? — UnladenSwallow (talk) 20:21, 19 September 2019 (UTC)

It seems to revolve around the quality of the Blog: WP:Blogs as sources. I see that Crimean Blog has been around since 2007, so they have been doing something right. Rowan Forest (talk) 21:49, 19 September 2019 (UTC)

WP:BLPSPS says:

Never use self-published sources—including but not limited to books, zines, websites, blogs, and tweets—as sources of material about a living person, unless written or published by the subject of the article. "Self-published blogs" in this context refers to personal and group blogs.

But Krymskiy blog is certainly not a personal blog or a group blog. It's a thematic blog that reposts Crimea-related articles from various media outlets. I guess that makes it not subject to WP:BLPSPS.

Since the post in question is a repost of the original Russkaya planeta article anyway, I'll go ahead and add information from it to the article and use {{cite web}}'s |archive-url= parameter or |url= + |via= parameters to link Krymskiy blog's repost. — UnladenSwallow (talk) 01:01, 20 September 2019 (UTC)

@UnladenSwallow: Yes, you can cite the interview to Russkaya planeta, with a |via= parameter to indicate the re-publishing on the blog. You could also search for the original article at archive.org. — JFG ^talk 06:32, 23 September 2019 (UTC)

Requested move 25 September 2019

2I/Borisov → Comet Borisov – Opening up a move discussion on this topic, because I'm genuinely curious whether or not a natural disambiguation based on precedents set by article titles such as Comet Hale–Bopp, Comet Hyakutake, Comet ISON, Comet Shoemaker–Levy 9, ect., would be accepted in this particular situation. – PhilipTerryGraham (talk · articles · reviews) 12:55, 25 September 2019 (UTC)

• Support, as done to other famous comets, such as Comet Kohutek, Comet Bennett, Comet Machholz, Comet Lulin, Comet Morehouse, etc. Rowan Forest (talk) 15:30, 25 September 2019 (UTC)
• Support — 1I/ʻOumuamua's article is titled simply ʻOumuamua, so I don't see why we can't use Comet Borisov or even Borisov (comet) as the title. Here are a few examples of "Comet Borisov" name used in the media:

• We Could Chase Down Interstellar Comet Borisov by 2045 (space.com, September 20, 2019)
• Comet Borisov: Interstellar visitor might just be the most important comet in our system (express.co.uk, September 18, 2019)
• Our best look at likely interstellar comet Borisov so far (cnet.com, September 13, 2019)

— UnladenSwallow (talk) 15:45, 25 September 2019 (UTC)

@UnladenSwallow: This might be a good case for common name recognition – the naming conventions for articles on astronomical objects preferences common names first, after all. – PhilipTerryGraham (talk · articles · reviews) 17:18, 25 September 2019 (UTC)

• Oppose at this time - To quote from the IAU press release: here, "In this case, the IAU has decided to follow the tradition of naming cometary objects after their discoverers, so the object has been named 2I/Borisov." So the official name for the object is "2I/Borisov". It seems premature to name the main article something else, unless and until we have a much longer history of other Reliable Sources using another term. Hallucegenia (talk) 16:43, 25 September 2019 (UTC)
• Strong Oppose, Unlike all above comets listed, 2I/Borisov is an object of interstellar origin, a class of object with exactly 1 existing precursor, 1I/ʻOumuamua. The listing of it as simply a "comet" Borisov would introduce unnecessary confusion in the title, not to mention the fact that the official title of it is 2I/Borisov and unlike any of the above comets, it's not going to be a great comet, or have any sort of exceptional qualities other than the fact that it's an interstellar comet, which is addressed quite succinctly already by the 2I designation. exoplanetaryscience (talk) 16:59, 25 September 2019 (UTC)

@Exoplanetaryscience: Two things to note though – 1) it is a comet, so it isn't necessarily confusing to call it as such, and 2) I'm not sure most readers would recognise what the designation "2I" even means, and it would be best to find a better disambiguator if "comet" doesn't suffice. – PhilipTerryGraham (talk · articles · reviews) 17:24, 25 September 2019 (UTC)

I'll give you that, those are both fair points. I suppose more what I was going for for the first thing was that calling a "comet" would be understating what its most notable feature is, when there is already an existing designation giving its most notable feature. Perhaps the 2I designation isn't the most obvious to a reader, and this is easily Borisov's most famous comet discovery, I still think there would need to be a lot of popular referring to it as "comet Borisov" rather than "2I/Borisov" for me to be convinced it's more appropriate of a title per WP:COMMONNAME

@Exoplanetaryscience: unlike any of the above comets, it's not going to […] have any sort of exceptional qualities other than the fact that it's an interstellar comet seems self-contradictory. The fact that it came from another star system makes it exceptional – perhaps, the most exceptional of all the comets listed above (of course, many comets are suspected of having extrasolar origin, but it's one thing to suspect, and another thing to know for a fact). — UnladenSwallow (talk) 19:09, 25 September 2019 (UTC)

Sorry about the ambiguity, what I'd meant is that its primary notable quality is the fact that it's an interstellar comet, and aside from that there isn't much to speak of, at least anything exceptionally article-worthy. exoplanetaryscience (talk) 20:12, 25 September 2019 (UTC)

@Exoplanetaryscience: But how is it different in this regard from other comets listed above? Comet Kohoutek's primary notable quality is the fact that it was overhyped as the "comet of the century". Comet Bennett and Comet Machholz do not seem to have any primary notable qualities. Comet Lulin's primary notable quality is that a team of Italian astronomers saw part of its tail get torn away. And so on and so forth. Do you mean to say that a comet should be large/bright/visible to the naked eye to be named "Comet (Discoverer's name)"? — UnladenSwallow (talk) 21:56, 25 September 2019 (UTC)

• Oppose at this time Pages that come up when I google Comet Borisov and 'in the last 24' use 2I/Borisov. Give it a couple of more days to see if it stays that way or if they start using Comet Borisov once it get more mainstream coverage. Agmartin (talk) 21:21, 25 September 2019 (UTC)
• Oppose for a simple reason: this is the eighth comet that Gennadiy Borisov has discovered (list here), and is unlikely to be the last. We don't yet know which (if any) should be the "Comet Borisov". I agree with a redirect because this is definitely the most famous (and currently newsworthy) so far, but a permanent name requires additional WP:Disambiguation. 38.39.199.2 (talk) 22:46, 25 September 2019 (UTC)
• Strong oppose as 38.39.199.2 above: what should we do with seven other "his" comets: C/2013 N4 (Borisov), C/2013 V2 (Borisov), C/2014 Q3 (Borisov), C/2014 R1 (Borisov), C/2015 D4 (Borisov), C/2016 R3 (Borisov), C/2017 E1 (Borisov) discovered since 2013? Julo (talk) 23:48, 25 September 2019 (UTC)
• Oppose Gennady Borisov has been known for his comet discoveries before he found 2I/Borisov. At least one of his finds (C/2014 Q3) has received considerable attention. 2I/Borisov may be his most significant find to date, but naming the article "Comet Borisov" would be premature. If that name becomes the WP:COMMONNAME in the literature then we can reconsider. We don't have a WP:CRYSTALBALL. Renerpho (talk) 00:46, 26 September 2019 (UTC)
• Oppose for reasons above (and for my personal preference to prefer IAU names). ― Дрейгорич / Dreigorich Talk 06:16, 26 September 2019 (UTC)
• Oppose: it is not a "random" comet, and before 2I was discovered, there were already 7 Solar-System comets named Borisov (see fr:Comète Borissov for the list). The IAU designation has the advantage to have no ambiguity. SenseiAC (talk) 16:10, 26 September 2019 (UTC)
• Oppose: For now, Comet Borisov does not represent the most common name. --Harlock81 (talk) 21:46, 26 September 2019 (UTC)

In case:

Right now there is an image from the Gemini Observatory in Hawaii of the comet [1]. However, this would be a non-free image presently, and there is a potential that NASA or other bodies will release a free image over the next 3-4 months as it nears. In case that does not happen by... say April 2020? then this would be a permissible use of a non-free image since we will likely never see this comet again in our current editors' lifetimes (eg no chance at a free image :) --Masem (t) 16:18, 25 September 2019 (UTC)

We will have NASA images by mid-October as the comet gets a greater solar elongation. -- Kheider (talk) 16:57, 25 September 2019 (UTC)

@Masem: You can put a link to it in the "External links" section. — UnladenSwallow (talk) 19:20, 25 September 2019 (UTC)

Good point. Could also be a {{external media}} template but I don't think there's a lot of side room with images there now. --Masem (t) 19:40, 25 September 2019 (UTC)

Well, the image of the comet is the first thing most people want to see, so I think {{external media}} is certainly warranted here and should take precedence over other images if necessary. — UnladenSwallow (talk) 20:14, 25 September 2019 (UTC)

I have a friend who took an image of the comet - if they gave permission for wikipedia to use it would that be enough to provide? or would it need to be released under CC? 134.114.223.244 (talk) 20:27, 25 September 2019 (UTC)

It seems that in this particular case a permission would be enough (see Wikipedia:Non-free content for details), but it would be better if he released it under CC. — UnladenSwallow (talk) 21:13, 25 September 2019 (UTC)

Well, we'd really can only accept a free image here - which either means public domain, or CC-BY or CC-BY-SA. Given that we can expect NASA to release an image too - which will be public domain due to NASA being a US Government agency, any non-free will not be helpful here. --Masem (t) 21:50, 25 September 2019 (UTC)

Actually, we can accept a non-free image here (with author's permission, of course), because there is no easy way to produce a free image of the comet (read the rules in Wikipedia:Non-free content). However, as soon as a free image becomes available, the non-free image must be immediately replaced. I agree with you that it's better to wait for the NASA image, which is likely to be of higher quality than the image taken by 134.114.223.244's friend. — UnladenSwallow (talk) 22:47, 25 September 2019 (UTC)

Just FYI, the {{external media}} template only drops a link in a floating box in the body, doesn't show the image. (This template also supports external video links too). --Masem (t) 21:50, 25 September 2019 (UTC)

Thanks, I know this. What I mean to say is that if the {{external media}} box says "Image of 2I/Borisov", everyone will click on it. And it should be placed near the top of the article, because most people would prefer to see the image first (in this case, a link to the image), orbits second. — UnladenSwallow (talk) 22:36, 25 September 2019 (UTC)

Page view log for this article

The page views shown in the log for this article are strangely low prior to two days ago. Does anyone know why that might be? ↠Pine (✉) 06:49, 26 September 2019 (UTC)

• • ↠Pine (✉) You are comparing the talk page views to the article views is my guess, was there a prize 121.99.108.78 (talk) 07:17, 26 September 2019 (UTC)

• No, I am looking at the page views for the article. --↠Pine (✉) 07:26, 26 September 2019 (UTC)

You need to check 2I/Borisov, C/2019 Q4 (Borisov) and gb00234 as the article has moved twice. -- Kheider (talk) 07:30, 26 September 2019 (UTC)

• Kheider thanks, I was looking at those earlier but I couldn't figure out what happened. I think that this article was previously at Q4 (Borisov), and while the content was moved here and replaced on the old page with a redirect, that was an error and instead the entire original page should have been moved here to keep the view log intact and so that page watchers could keep the current page on their watchlists. Then a new redirect page could be created under the old page name. ↠Pine (✉) 07:33, 26 September 2019 (UTC)

The revision history is intact, so the article has been moved properly. I guess the Move action doesn't carry over the page views. — UnladenSwallow (talk) 10:24, 26 September 2019 (UTC)

I believe the pageviews list the number of hits to the first wikipedia page that receives the hit so if someone searched for an old name it gets counted there and not to where it redirects. If you plot all three of the names you will see that pageviews are still being tabulated for C/2019 Q4 (Borisov) and gb000234. Some were being counted for 2I/Borisov even before the name change and are also being counted for Comet Borisov which only exists as a redirect. Agmartin (talk) 17:20, 26 September 2019 (UTC)