Interstellar Comet 3I/Atlas: What We Know Now
skyandtelescope.org
Interstellar Comet 3I/Atlas: What We Know Now
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Re: Interstellar Comet 3I/Atlas: What We Know Now
#2> The Rubin team realized that their telescope had — unbeknownst to them — imaged the object starting 10 days before its discovery.
This is so cool! Vera Rubin is designed to detect lots and lots of similar things, and having a test case where they can go back and "track" 3I through data is probably a great thing for tuning their models. Can't wait to see what Rubin finds over the years.
Also, it's so cool that they found 3I pretty early, we'll now have lots and lots of data from multiple powerful observatories and probably from some remote ones as well. It's nuts that we'll probably get some images/data from probes out in the solar system (mars orbiters, maybe JUICE).
Re: Interstellar Comet 3I/Atlas: What We Know Now
#3> The Rubin observations also show hints of a dusty tail, but oddly this elongation points directly toward the Sun. Typically, the push of the Sun’s radiation moves dust in comet’s tails so that it points away from the Sun.
Deceleration burn?
Re: Interstellar Comet 3I/Atlas: What We Know Now
#4I'm inspired to re-watch Don't Look Up this afternoon.
Re: Interstellar Comet 3I/Atlas: What We Know Now
#5Related:
Astronomers discover 3I/ATLAS – Third interstellar object to visit Solar System (308 points, 26 days ago, 171 comments) https://news.ycombinator.com/item?id=44451329
Vera C. Rubin Observatory Observations of Interstellar Comet 3I/Atlas (3 points, 7 days ago) https://news.ycombinator.com/item?id=44638392
Feasibility of a Spacecraft Flyby with the Third Interstellar Object 3I/Atlas (3 points, 6 days ago) https://news.ycombinator.com/item?id=44649150
First Hubble telescope images of interstellar comet 3I/ATLAS (109 points, 6 days ago, 29 comments) https://news.ycombinator.com/item?id=44649653
Re: Interstellar Comet 3I/Atlas: What We Know Now
#6Could an object like 3I theoretically tell when eyes are being pointed at it?
Probably not ground-based eyes, but possibly Hubble.
i.e. "the inhabitants are scanning us"
Re: Interstellar Comet 3I/Atlas: What We Know Now
#7I'm inspired to re-watch Don't Look Up this afternoon.
At a closest approach of 1.8AU, you really don't have to worry about a collision with Earth.
But that film is relevant to this comet in another way -- several missions that made it into space before the administration's war on the scientific enlightenment may be able to image the comet when we can't see it (perihelion) or when they're much closer to it than we'll ever be.
Re: Interstellar Comet 3I/Atlas: What We Know Now
#8> The Rubin observations also show hints of a dusty tail, but oddly this elongation points directly toward the Sun. Typically, the push of the Sun’s radiation moves dust in comet’s tails so that it points away from the Sun. Deceleration burn?
I guess at some point we should expect dust to launch toward the Sun as that side gets heated more, right? But I have no idea when that is supposed to happen…
Re: Interstellar Comet 3I/Atlas: What We Know Now
#9Could an object like 3I theoretically tell when eyes are being pointed at it? Probably not ground-based eyes, but possibly Hubble. i.e. "the inhabitants are scanning us"
I don't believe so, unless the object had such a powerful telescope it could image Hubble itself in high definition and literally see where it was pointing, which would require an absurdly large lens. A telescope like Hubble absorbing light is purely passive, it doesn't emit anything "back" that would tell the observed object it is being observed.
Re: Interstellar Comet 3I/Atlas: What We Know Now
#10Could an object like 3I theoretically tell when eyes are being pointed at it? Probably not ground-based eyes, but possibly Hubble. i.e. "the inhabitants are scanning us"
Observing passive observation systems over those distances is pretty unlikely even with an optimistic view of future technology. But perhaps not impossible.
We have all kinds of space radars though that are active.