Anyone hear of any recent observations of 2I/Borisov? It’s an interstellar comet (the first was Oumuamua) that was supposed to reach its closest point to earth on December 28th. There doesn’t seem to be any new information on the NASA site or elsewhere. Is it too soon to expect to see news? Can we expect to see better images?
Bumping this in case it went unnoticed.
Which is what astronomers expect from such interstellar bodies. Differences from Solar System comets are expected to show up in isotope ratios, which will require analysis of its spectrum.
Based on the abstract of that paper, they were only analysing for molecular composition, (e.g. CN, C[sub]2[/sub], OH) but not isotope ratios (e.g. hydrogen/deuterium, [sup]16[/sup]O/[sup]18[/sup]O). A quick google search does not produce a paper on this topic.
Fine–in some obscure isotope ratio this comet may be very slightly different enough from any ordinary solar system comet that some subset of astrochemists will be pretty excited about the results. That good enough for you?
That would actually be surprising. Interstellar comets should have significantly different isotope ratios, so one being almost the same as Solar System comets would be unexpected.
I’m not an expert, but it may be that Borisov is not bright enough to do isotopic analysis on. The differences in the spectra of isotopes is much more subtle than those between different molecules and atoms. So you need a brighter spectrum to do the analysis.
Maybe someone can answer one or more of the three questions in my post:
*Anyone hear of any recent observations of 2I/Borisov?
Is it too soon to expect to see news?
Can we expect to see better images?*
That’d be swell.
The latest news I’ve heard was from a month ago: Hubble images. I doubt if we’ll get much better images, since it’s not getting closer to Earth. And I’m not sure what kind of news you’re expecting.
I did answer your question. The site I linked (NASA itself) is the best picture that there is and that there is going to be. And–as I have been pointing out–it is behaving like a perfectly ordinary local comet, so nothing in the image is going to look different from any other not especially bright, not especially close to Earth comet. What “news” are you hoping for?
Thank you for your response.
If in fact isotopic ratios are the same, or very close, to our in-system comets that’s fascinating. It potentially means the comet came from a system born out of the same stellar cradle as our sun.
Bumping this for a small update.
Here’s the first report I’ve seen about Borisov in a couple months. The image is the same as the last report, as far as I can tell. Other than the new estimate of the size, there’s not much there.
Can you even determine isotopic ratios with optical spectrometry? Molecular structure of simple molecules? Sure. Isotopes? I doubt it.
I am not an astrophysicist, but have had a long career determining isotope levels with mass spectrometry. If there’s an optical method, I am not aware of it (which doesn’t mean it doesn’t exist).
I recently read a similar article based on that same Nature paper that suggested the hypothesis that 2I/Borisov may have formed around a cool star, such as a brown dwarf, and hence the large amount of CO ice.
In principle you can, if the spectroscopy is precise enough. Though lots of luck getting it to work for anything beyond H1 vs. deuterium.