[HN Gopher] Vera C. Rubin Observatory first images
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Vera C. Rubin Observatory first images
Author : phsilva
Score : 185 points
Date : 2025-06-23 15:41 UTC (7 hours ago)
(HTM) web link (rubinobservatory.org)
(TXT) w3m dump (rubinobservatory.org)
| phsilva wrote:
| https://skyviewer.app/
| NitpickLawyer wrote:
| So stoked for this observatory to go online! One cool uses it'll
| excel at is taking "deltas" between images and detect moving
| stuff. Close asteroids is one obvious goal, but I'm more
| interested in the next Oumuamua / Borisov like objects that come
| in from interstellar space. It would be amazing to get early
| warnings about those, and be able to study them with other
| powerful telescopes we have now.
| avmich wrote:
| > So stoked for this observatory to go online!
|
| Second this, but other areas are of great interest too. Kuiper
| Belt discoveries and surveys FTW!
| jasonthorsness wrote:
| Why are there lens-flare-like artifacts around some of the bright
| objects?
| NitpickLawyer wrote:
| Those are diffraction spikes, caused by how the light interacts
| with the support structure holding the secondary mirror. Each
| telescope has different patterns, hubble, jwst, etc. I think
| they only happen for stars, and not for galaxies (an easy way
| to know which is which), but I might be wrong on that (there's
| a possibility for faint stars not to have them IIRC).
| perihelions wrote:
| > _" Each telescope has different patterns"_
|
| This one's extra-special! The pattern is multiple + shapes,
| rotated and superimposed on top of each other. _And they 're
| different colors!_ That's this telescope's signature scanning
| algorithm--I don't know what that is, but, it's evident it
| takes multiple exposures, in different color filters, with
| the image plane rotated differently relative to the CCD plane
| in each exposure. I assume there's some kind of signal
| processing rationale behind that choice.
|
| edit: Here's one of the bright stars, I think it's HD 107428:
|
| https://i.ibb.co/HTmP0rqn/diffraction.webp
|
| This one has asteroid streaks surrounding it (it's a toggle
| in one of the hidden menus), which gives a strong clue about
| the timing of the multiple exposures. The asteroids are going
| in a straight line at a constant speed--the spacing and
| colors of the dots shows what the exposure sequence was.
|
| I think this quote explains the reason they want to rotate
| the camera:
|
| > _" The ranking criteria also ensure that the visits to each
| field are widely distributed in position angle on the sky and
| rotation angle of the camera in order to minimize systematic
| effects in galaxy shape determination."_
|
| https://arxiv.org/abs/0805.2366 ( _" LSST [Vera Rubin]: from
| Science Drivers to Reference Design and Anticipated Data
| Products"_)
| IAmBroom wrote:
| No, they happen for absolutely every externally-generated
| pixel of light (that is, not for shot noise, or firelflies
| that happen to fly between the mirrors). Where objects
| subtend more than one pixel, each pixel will generate it's
| own diffraction patterns, and the superposition of all are
| present in the final image. Of course, each diffraction
| pattern is offset from the next, so they mostly just broaden
| (smear out), not intensify.
|
| However, the brightness of the diffraction effects is much
| lower than the light of the focused image itself. Where the
| image is itself dim, the diffraction effects might not add up
| to anything noticeable. Where the image supersaturates the
| detector (as can happen with a 1-pixel-wide star), the "much
| lower" fraction of that intensity can still be annoyingly
| visible.
| petee wrote:
| The same effect is used for Bahtinov focusing masks. From
| what i know, all light will bend around the structures, but
| stars are bright and focused enough to see; in theory
| galaxies would too
| pantalaimon wrote:
| Those are stars, they create those lens flares because they are
| so bright.
|
| All the dim fuzzy objects are galaxies much further away.
| perihelions wrote:
| Here's the SDSS view[0] of this featured[1] section from the
| Virgo Cluster, in comparison, to put the staggering depth of
| these exposures in their proper context,
|
| [0]
| https://aladin.cds.unistra.fr/AladinLite/?target=12%2026%205...
|
| [1] https://rubinobservatory.org/gallery/collections/first-
| look-...
| tominspace7 wrote:
| With an opacity slider, for easy comparison:
|
| https://aladin.cds.unistra.fr/AladinLite/?baseImageLayer=CDS...
| dekhn wrote:
| I really like the Rubin because I think a lot of people focus too
| much on "deep" seeing (IE, looking at individual or several
| objects with very high magnification only once). The Rubin does
| much more "wide" seeing and this actually produces a ton of
| useful data- basically, enough data to collect reliable
| statistics about things. This helps refine cosmological models in
| ways that smaller individual observations cannot.
|
| What's amazing to me is just how long it took to get to first
| photo- I was working on the design of the LSST scope well over 10
| years ago, and the project had been underway for some time before
| that. It's hard to keep attention on projects for that long when
| a company can IPO and make billions in just a few years.
| cogman10 wrote:
| Deep is still interesting in understanding the origins of the
| universe. Rubin seems highly practical on the flip side. It'll
| be a super helpful tool in predicting asteroid impacts.
| TheBlight wrote:
| Or detecting more unusual interstellar objects like
| 'Oumuamua.
| WD-42 wrote:
| Also microlensing events, supernovae, and many other things
| in our very dynamic universe.
| perihelions wrote:
| Also new planets! Planet Nine should likely be resolved
| within months, one way or another.
|
| > _" Probably within the first year we're going to see if
| there's something there or not," says Pedro Bernardinelli,
| an astronomer at the University of Washington."_
|
| https://www.nationalgeographic.com/science/article/is-
| there-...
| krunck wrote:
| The asteroid detection capability is amazing:
| https://rubinobservatory.org/news/rubin-first-look/swarm-ast...
| cogman10 wrote:
| This is really going to revolutionize our ability to detect and
| predict asteroid impact.
| stronglikedan wrote:
| And just in the nick of time!
| jstummbillig wrote:
| That is likely the most unexcitedly unsettling video I have
| ever seen. Amazing storytelling really.
| stronglikedan wrote:
| I was just coming back to comment on the existential dread
| elicited by that video.
| m3kw9 wrote:
| Which also tells the astronomical low odds of asteroids hitting
| earth even with "so many" of them. To me it changes nothing
| bjt wrote:
| If it has the potential to wipe out our entire species, but
| there's something we could do to prevent it (which I'm not
| sure about w/r/to asteroids), then it's worth looking out for
| the black swan event.
|
| Doing some extremely rough math along these lines to double
| check myself:
|
| * Gemini says that a dinosaur-extincting asteroid hits Earth
| about once every 100 million years. So in any given year
| that's 0.000001%.
|
| * Economists say a human life is worth about 10 million
| dollars. There are about 8 billion people on Earth. So the
| total value of all human life is $80,000,000,000,000,000 (or
| 8e+16).
|
| * So in any given year, the present value of asteroid
| protection is $800,000,000 (likelihood of an impact that year
| times value of the human life it would wipe out).
|
| * The Guardian says the Vera Rubin telescope cost about
| $2,000,000,000 (2 billion).
|
| By that measure, assuming the Rubin telescope prevents any
| dinosaur-extinction-level asteroid impacts, it will pay for
| itself in three years.
|
| https://www.npr.org/transcripts/835571843
| boznz wrote:
| Wow, they should have led with this.
| jcims wrote:
| Whoa that's incredible.
|
| (And amazing production of the actual video as well)
|
| Pretty sure you can see some kind of masking for satellites in
| some of the frames of the asteroid videos.
| dang wrote:
| Related: https://www.nytimes.com/2025/06/23/science/vera-rubin-
| scient...
|
| (via https://news.ycombinator.com/item?id=44352455, but no
| comments there)
| -warren wrote:
| Counter-rotating spiral galaxies. Super neat!
| https://skyviewer.app/embed?target=186.66721+8.89072&fov=0.2...
| japhyr wrote:
| That is interesting!
|
| They look like they're roughly in the same plane. Is it safe to
| assume they're roughly in the same plane, or could they be
| really distant along the line of sight? The similarity in size
| makes me think they are, but I don't have any reason to be
| confident in that judgment.
| perihelions wrote:
| Those are NGC 4411 a+b and they're indeed right next to each
| other,
|
| https://noirlab.edu/public/images/iotw2421b/ ( _" thought to
| be right next to each other -- both at a distance of about 50
| million light-years"_)
| jcims wrote:
| What's going on directly above with what looks to be 3-4
| galaxies interacting?
| perihelions wrote:
| > _"?target=186.66721+8.89072 "_
|
| (For those who haven't noticed, you can just simply paste
| 186.66721+8.89072 or whichever target you're curious about in
| an astronomy database like Aladin[0], and there right-click on
| "What is this?")
|
| [0]
| https://aladin.cds.unistra.fr/AladinLite/?target=12%2026%204...
| jcims wrote:
| (Quick side note, if you go to /explorer instead of /embed you
| can zoom out so you can see the whole image at once)
|
| https://skyviewer.app/explorer?target=187.69717+12.33897&fov...
| jlarocco wrote:
| I wonder if there's some kind of gravitational lensing going
| on. A lot of the galaxies look similar, but in different
| orientations.
|
| https://skyviewer.app/embed?target=186.66721+8.89072&fov=0.2...
|
| https://skyviewer.app/embed?target=185.46019+4.48014&fov=0.6...
|
| https://skyviewer.app/embed?target=188.49629+8.40493&fov=1.3...
| ramijames wrote:
| I was surprised by how many lensed objects I could spot.
| kdamica wrote:
| My God, it's full of stars
| trhway wrote:
| brings up that old paradox - should any line of sight
| ultimately end up at a star?
| WD-42 wrote:
| The amount of data this thing will be putting out every night is
| insane. For years now the community has been building the
| infrastructure to be able to efficiently consume it for useful
| science, but we still have work to do. Anyone interested in the
| problem of pipelining and distributing 10s of TB of data a night
| should check out the LSST and related GitHubs.
| runako wrote:
| Every set of deep field imagery reminds me that any point of
| light we see could be a star, a galaxy, or a cluster of galaxies.
| The universe is unimaginably vast.
|
| For observatories like Rubin, is there a plan for keeping them
| open after the funding ends? Is it feasible for Chile to take
| over the project and keep it going?
|
| On a practical note, what happens to a facility like this if one
| day it's just locked up? Will it degrade without routine
| maintenance, or will it still be operational in the event someone
| can put together funding?
| w10-1 wrote:
| The zoomed images look grainy as one would expect from raw data,
| but I would have expected them to do dark field subtraction for
| the chips to minimize this effect. Does anyone know if that's
| done (or expressly avoided) in this context, or why it might not
| be as helpful (e.g., for longer exposures)?
| jcims wrote:
| Seems this will be done on the 'nightly' release cadence. Found
| on page 11 in this doc that I found from the wikipedia page:
|
| https://docushare.lsstcorp.org/docushare/dsweb/Get/LSE-163/L...
| mapt wrote:
| Even one zoom-in and I find something interesting.
|
| What's that faint illuminated tendril extending from M61 (the
| large spiral galaxy at the bottom center of the image) upwards
| towards that red giant? It seems too straight and off-center to
| be an extension of the spiral arm.
| ludsan wrote:
| something green:
| https://skyviewer.app/embed?target=186.82033+8.25479&fov=0.0...
| botswana99 wrote:
| Jesus H Christ, the Universe is big.
| xoxxala wrote:
| "Space is big. You just won't believe how vastly, hugely, mind-
| bogglingly big it is. I mean, you may think it's a long way
| down the road to the chemist's, but that's just peanuts to
| space." -Douglas Adams
| jcims wrote:
| The wikipedia article is quite good -
| https://en.wikipedia.org/wiki/Vera_C._Rubin_Observatory (Edit:
| Treasure trove of details in the references if any of your
| interests are adjacent to this)
|
| The image of the woman holding the model of the sensor is nice
| because it includes a moon for scale.
|
| Question I was curious about is whether or not the focal plane
| was flat (it is).
|
| This is an interesting tidbit:
|
| > _Once images are taken, they are processed according to three
| different timescales, prompt (within 60 seconds), daily, and
| annually._
|
| > _The prompt products are alerts, issued within 60 seconds of
| observation, about objects that have changed brightness or
| position relative to archived images of that sky position.
| Transferring, processing, and differencing such large images
| within 60 seconds (previous methods took hours, on smaller
| images) is a significant software engineering problem by itself.
| This stage of processing will be performed at a classified
| government facility so events that would reveal secret assets can
| be edited out._
|
| They are estimating 10 million alerts per night, which will be
| released publicly after the previously mentioned assessment takes
| place.
| robotnikman wrote:
| >The prompt products are alerts, issued within 60 seconds of
| observation, about objects that have changed brightness or
| position relative to archived images of that sky position.
| Transferring, processing, and differencing such large images
| within 60 seconds (previous methods took hours, on smaller
| images) is a significant software engineering problem by
| itself.[64]
|
| >This stage of processing will be performed at a classified
| government facility so events that would reveal secret assets
| can be edited out.
|
| Interesting, I'm guessing secret spy satellites?
| kkylin wrote:
| "Let's look for spy satellites / orbiters" was an
| "application" I wondered about. My second thought about this
| was: maybe the US (and possibly other countries) already have
| something like this, but classified?
| dekhn wrote:
| The US already has a very sophisticated system for this.
|
| https://en.wikipedia.org/wiki/United_States_Space_Surveilla
| n...
| realo wrote:
| .. and aliens, of course ...
| gmueckl wrote:
| I expect a lot of events to get filtered that foreign
| governments expect to stay reasonably secret, even if they
| aren't friendly with the US. It's a game.
|
| The thing that really saddens me is that the military gets to
| filter the data first and scientists only get to see the
| already manipulated data instead of a raw feed from their own
| instrument.
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(page generated 2025-06-23 23:00 UTC)