[HN Gopher] New telescope images of Jupiter's moon Io rival thos...
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New telescope images of Jupiter's moon Io rival those from
spacecraft
Author : wglb
Score : 172 points
Date : 2024-06-04 01:57 UTC (21 hours ago)
(HTM) web link (phys.org)
(TXT) w3m dump (phys.org)
| whimsicalism wrote:
| The telescope photo:
| https://scx2.b-cdn.net/gfx/news/hires/2024/glimpses-of-a-vol...
|
| Stitched spacecraft photo:
| https://science.nasa.gov/resource/high-resolution-global-vie...
|
| This seems awesome but I would say 'rival those' is a bit of a
| stretch
| OldGuyInTheClub wrote:
| I was quite taken by the ground-based photo but agree with you
| upon comparing the links. 50 mile resolution (LBT) vs. 1.6
| miles (Galileo) is pretty cut-and-dried. Maybe the point is
| that LBT can do this for other objects not around Jupiter?
| WillAdams wrote:
| Exactly --- a fly-by of everything in the asteroid belt for
| example would be a budget-buster --- what is there in the
| belt which it would be interesting to have photos of?
| dylan604 wrote:
| My high score!! Or we could see which asteroid Han Solo is
| hiding the Millennium Falcon in. Or we could see all of the
| illegal mining operations by those pesky guys from Plural
| Zed Alpha Nine Nine.
|
| We don't know what we won't see until we don't see it.
| max-ibel wrote:
| I agree; I'm thinking that's it's useful to be able to get
| frequent snapshots of the whole moon at this resolution (if you
| are interested in time lapse to track volcanic activity for
| instance). The satellite-based stitched photo probably took a
| long time to collect.
|
| Also, without knowing details, I suspect you can improve the
| LBT images as the system matures, but as you say, probably not
| at the resolution the satellite provides.
| boffinAudio wrote:
| It depends what the parameters for rivalry are .. a ground-
| based telescope can take multiple photo's, perhaps even
| thousands, at very low cost - although the resolution may not
| be comparable, this doesn't discount the value of the _data_ to
| the scientists who are obtaining it at _a far greater reduction
| of cost and effort_ than those who rely on space-based
| instruments. Remember, we don 't have a permanent instrument
| stationed at Io - these spacecraft are doing fly-by's and thus
| have a limited window of opportunity.
|
| So, while the resolution may be great eye-candy, the
| consistency of the data over time is vastly different. "Higher
| resolution" does not always mean "better science", especially
| if its a one-shot compared to thousands of data-samples...
| rbanffy wrote:
| It rivals images from spacecraft in Earth orbit - as in Hubble
| or Webb. It won't rival images from cameras sent to the near
| vicinity of the targets, but those can take decades from the
| moment you decide to take a picture to the time you take it,
| unless you already decided you'd take some pictures from that
| general location decades prior.
| shiroiushi wrote:
| >It rivals images from spacecraft _in Earth orbit_ - as in
| Hubble or Webb. (emphasis mine)
|
| It seems like this critical detail was left out of the
| headline.
| rbanffy wrote:
| Still technically correct, the best kind of correct. I
| wonder how much cheaper are land-based telescopes over the
| lifetime of instruments such as the Hubble or the Webb.
|
| Also, a huge shame the Overwhelmingly Large Telescope was
| cancelled. We need more creative names for those.
| kloch wrote:
| Angular resolution through the Atmosphere has been solved
| with adaptive optics and advanced mathematical
| techniques.
|
| Unfortunately, nothing can remove the temperature of the
| atmosphere (which affects infrared imaging), or the
| absorption of many wavelength bands.
| alfiopuglisi wrote:
| > I wonder how much cheaper are land-based telescopes
| over the lifetime of instruments such as the Hubble or
| the Webb.
|
| 10-100 times cheaper. An LBT night is around $50k-100k,
| which over 10 years corresponds to $300 millions. JWST
| total budget is about $10 billions.
|
| True, JWST can operate close to 24/7. On the other hand,
| land-based telescopes are under constant refurbishment
| and upgrades, and they become more powerful over time.
| WrongAssumption wrote:
| Doesn't change your point, as I believe you are mainly
| referring to distance from the object being observed. But
| Webb orbits the sun.
| holoduke wrote:
| That telescope image is the current highest res. Not from the
| new telescope. That is yet to be released.
| petesergeant wrote:
| Are you sure? The image is captioned:
|
| "Jupiter moon Io, imaged by SHARK-VIS on Jan. 10, 2024. This
| is the highest resolution image of Io ever obtained by an
| Earth-based telescope"
| wthomp wrote:
| I visited the Large binocular telescope just a month or two ago.
| A very impressive facility, and one can only imagine the image
| quality if they were captured using both mirrors coherently.
| eternauta3k wrote:
| For those interested in the telescope, I highly recommend this
| Omega Tau episode: https://omegataupodcast.net/111-optical-
| astronomy-and-the-la...
| ggm wrote:
| You would think an article comparing images would.. well would
| show you the two images side-by-side.
|
| From the post(s) below It's impressive but its definitely lower
| res.
|
| Over the life of managing telescopes, is it actually cheaper than
| a craft in orbit?
| pulvinar wrote:
| Yes, the LBT could theoretically do 0.006 arcsecond resolution
| in binocular configuration (22.8 meter aperture), which is
| about 14 feet at Jupiter distance, or 10 times worse at best.
| But then it costs 10 times less, and can see the whole universe
| at that resolution.
| dakr wrote:
| Presumably you meant to say 14 miles, not 14 feet. Also,
| since the adaptive optic system acts on the near-IR light,
| let's shift the 500nm used to calculate the Rayleigh
| criterion to at least 1 micron, which doubles the limiting
| resolution to around 0.011 arcsec.
| SiempreViernes wrote:
| Close, 16 mas in R: https://sites.google.com/inaf.it/shark-
| vis/home
| pulvinar wrote:
| Yes, sorry, 14 miles (a wishful typo!)
| lokimedes wrote:
| Somebody should make a cave painting of these worlds, you know,
| just in case...
| yayr wrote:
| well, we've already buried all of github in the arktic,
| probably should do that with some llms as well
| CamperBob2 wrote:
| Rod Serling beat us to it, I think:
| https://www.imdb.com/title/tt0734669/
| yayr wrote:
| it looks like for around 1 BTC you could get one full night
| access to this amazing instrument :-)
|
| (you'll probably have to convert it to cash though before)
| https://www.lbto.org/lbt-access/
| ItsBob wrote:
| Could they use the high-res orbiter photos, and the lower-but-
| still-really-good ground-based photos and use some sort of AI
| algo to enhance the ground-based ones?
|
| The idea being that they have high-res reference photos that are
| a one-shot deal but can take regular earth-based ones auto-
| enhance them from now on.
|
| It could then show changes over time in high res?
|
| I'm showing my limitations here, obviously, but I know what I
| mean... it makes sense in my head :)
| sandos wrote:
| Sure, super-resolution exists in various forms and this is one.
| But this is an example of not actually adding any scientific
| information to the photo: extraplating data like that will
| never yield anything new or unexpected, so...
| dylan604 wrote:
| But for what purpose would an AI generative assisted image
| actually do for science? This is an issue I have with the gung-
| ho AI crowd that thinks AI should be used for anything and
| everything all the time.
|
| Even if you trained the model against the most detailed images
| available. That data was a mere snapshot of the exact time it
| was taken which in some cases is decades old. If things are
| actually changing on these bodies, then using that stale data
| to update current images would actually be damaging to science
| as it would be attempting to make the current look like the
| old. No! We need to see what it looks like now for the
| comparisons.
|
| Enhance! It can only go so far. Otherwise, you're just a low-
| rent Hollywood SFX team generating new worlds for whatever
| space opera you weren't hired to work on.
| SiempreViernes wrote:
| An Italian instrument apparently, built by the Rome observatory:
| https://sites.google.com/inaf.it/shark-vis/home
| jiggawatts wrote:
| <moved>
| perihelions wrote:
| Wrong thread!
| ricksunny wrote:
| Sometimes (usually?) the tool is more interesting than the
| science it enables.
| bhouston wrote:
| I would expect that the James Webb telescope could create even
| better images of Io if they pointed it there? As long as it could
| focus range to look at nearby objects...
| mikepurvis wrote:
| Isn't JWST mostly about infrared though? That's the reason it
| has to be at L2, because those measurements are so much more
| sensitive to interference.
|
| These new Io images are in the visible spectrum, so it might be
| more apt to compare it to Hubble.
| BurningFrog wrote:
| True, but infrared images should have value in addition to
| the visible light images.
| itishappy wrote:
| See for yourself:
|
| https://news.berkeley.edu/2023/07/27/james-webb-space-telesc...
| dylan604 wrote:
| Expecting "better" from JWST compared to the image from TFA
| or even Hubble is definitely a misunderstanding of the
| differences between observation platforms. Just because the
| JWST mirror is larger than the Hubble's does not mean it will
| produce a "better" image as they are looking at different
| frequencies of light. Thinking that JWST will produce the
| same type of image with more detail/resolution is an
| incorrect way of thinking of the JWST's purpose.
| VikingCoder wrote:
| If I'm doing my math correctly, Io covers about 0.06% as many
| degrees of our vision from Earth as the moon does. (I'm not good
| at this math, but I'm trying.)
|
| Io Diameter 2263.8 miles
|
| Jupiter Distance to Earth 444000000 miles
|
| Perp / Base 0.000005098648649
|
| Radians 0.000005098648649
|
| Degrees 0.0002922792219
|
| Arc Seconds 1.052205199
|
| ===
|
| Moon Diameter 2159.1 miles
|
| Moon Distance to Earth 238900 miles
|
| Perp / Base 0.009037672666
|
| Radians 0.009037426614
|
| Degrees 0.5180690416
|
| Arc Seconds 1865.04855
| IncreasePosts wrote:
| The moon and Io are roughly the same diameter, so you can just
| divide Io's distance by the moon's distance to get the ratio of
| their perceived size without futzing with angles or geometry.
| VikingCoder wrote:
| Good point! With that shortcut, yeah, it's about 0.05% of the
| apparent diameter. So the math seems to check out.
| jcims wrote:
| IO's diameter ~3600km
|
| Avg distance to earth ~628m km
|
| Apparent diameter is ~5 microradians or ~1 arcsecond
|
| Similar to imaging a marble 5mm in diameter from 1km away.
|
| Betelgeuse is ~1.2 billion km in diameter (for now, lol)
|
| It's 642 light years away.
|
| It's apparent diameter is .2 microradians, or approximately a red
| blood cell from 35m away.
|
| Space is big. Things are small.
| minimalc wrote:
| I work for the company (Oxford Instruments Andor) that produces
| the cameras for this telescope:
| https://sites.google.com/inaf.it/shark-vis/instrument/detect... A
| great achievement!
|
| It's very exciting to be a (small) part of this, happy to answer
| any camera software questions (can't speak for the observatory's
| software though as I haven't seen it)
| hindsightbias wrote:
| Is this installed on one of the telescopes or integrated
| between both? I read about the LBT once and it seemed some
| instruments were on one and some were integrated. I assume it's
| used as a mono and binoc platform, depending.
| minimalc wrote:
| I'm not quite sure about their exact optical setup, I know
| the Zyla's are used in the shark-vis instrument[0]. I would
| guess from their article that one Zyla is dedicated to
| adaptive optics and one for imaging.
|
| [0] https://sites.google.com/inaf.it/shark-
| vis/instrument/detect...
| alfiopuglisi wrote:
| > I assume it's used as a mono and binoc platform, depending.
|
| Correct, it depends on the observation. Both sides have
| adaptive optics correction, but they work independently. This
| particular instrument (SHARK-VIS) is mounted on the "right"
| side, while SHARK-NIR is on the "left" side.
| GrantMoyer wrote:
| Awesome work!
|
| Are the cameras similar to what's in a consumer digital camera,
| that is, a single image sensor behind a bayer filer and a lens?
| Or does it use some other configuration, like an array of image
| sensors?
|
| And does sensor readout work similarly to a consumer camera,
| sequentially reading out rows of sensor data? Is there any cool
| software processing during the capture, like decovolution?
| minimalc wrote:
| > Are the cameras similar to what's in a consumer digital
| camera, that is, a single image sensor behind a bayer filer
| and a lens?
|
| Yes they're quite similar to consumer camera sensors, our
| sensors are usually from high quality production bins. We
| advertise this quality as "scientific CMOS" (sCMOS) to help
| highlight this. Consumer sensors can have a significant
| number of sensor defects which can be corrected so they
| aren't noticeable in casual photographs, but these defects
| are very detrimental for scientific imaging where quality is
| paramount. Another big difference is the noise and quantum
| efficiency characteristics of the sensor which is another key
| requirement for scientific instruments.
|
| We don't supply lens', I think the logic is that scientific
| customer's know exactly what kind of optical setup they want
| so most customer's would tend to use their own optical
| equipment or buy it in.
|
| Our camera's are monochrome (scientific cameras tend to care
| more about raw resolution than having a smaller res with
| bayer layer) so customers typically use different
| color/wavelength filters to get what they want and process
| them into true color images later if needed.
|
| > Or does it use some other configuration, like an array of
| image sensors?
|
| This particular camera, the Zyla has just one sensor. Though
| it is a little unique in our portfolio, in that the sensor
| can be read out from both halves simultaneously in various
| patterns. If your interested in the hardware we provide lots
| of info in our hardware manual: https://andor.oxinst.com/down
| loads/uploads/Zyla_hardware_use... I don't think we offer
| multi-sensor solutions, though I could be wrong.
|
| > And does sensor readout work similarly to a consumer
| camera, sequentially reading out rows of sensor data?
|
| Yes, there are two electronic shuttering modes we offer:
| rolling and global. Rolling takes a sequential row by row
| readout, and global does a readout of the entire sensor. The
| camera's used by the observator can only do rolling, but we
| have other Zyla models which also do global. There can be
| tradeoffs in choosing which one to use, typically framerate,
| noise and image distortion are the key factors in choosing.
| Global is available on some high end consumer cameras, but
| generally most consumer sensors will do rolling. Though this
| may have changed since I last looked.
|
| > Is there any cool software processing during the capture,
| like decovolution?
|
| In the camera side of the company, we try to leave the image
| as clean and raw as possible. We perform correction
| processing during acquisition on the camera; as high quality
| as the bins are, you still have to correct and characterize
| for various things to get the best performance in a
| scientific scenario.
|
| In the applications side of the company we do all kinds of
| image processing: deconvolution (this is a big deal in the
| confocal microscopy world, we have our own patented
| deconvolution method: srrf-stream) https://fusion-benchtop-
| software-guide.scrollhelp.site/fusio..., AI analysis, 3d/4d
| imaging (https://imaris.oxinst.com/). Probably lots more I
| don't know about (I'm on the camera side).
| drewrv wrote:
| How does the "compensation for atmospheric turbulence" work? It
| honestly sounds impossible, like those tv shows where the
| detective "enhances" a blurry photo.
| alfiopuglisi wrote:
| It's a technological tour-de-force involving deformable
| mirrors that change shape every millisecond, cameras able to
| count every incoming photon, and special computers designed
| to calculate the next correction within microseconds. As
| usual wikipedia has an introduction:
| https://en.wikipedia.org/wiki/Adaptive_optics
|
| Or try: https://andor.oxinst.com/learning/view/article/introd
| uction-...
| minimalc wrote:
| Sorry I'm not a big expert in the field of optics, but I am
| aware of our cameras being used to perform adaptive optics
| and lucky imaging.
|
| Adaptive optics in particular requires very fast framerates
| and low latency to make rapid adjustments to the mirror's
| shape to compensate for the constantly changing atmosphere.
| It's really amazing that it's possible at all! I believe this
| is the method used here, though I can't say with certainty.
|
| Lucky imaging is more akin to a brute force method, where you
| acquire lots and lots of images quickly and process the best
| ones when the atmosphere was being particularly cooperative
| at the time and not distorting the image very much.
|
| Again, there are lots of experts out there on the topic, this
| is just my simple view into it.
| dekhn wrote:
| The replies already posted are quite good. Let me explain it
| a different way:
|
| When light passes through the atmosphere, it undergoes a
| convolution known as a point spread function (think of it as
| convolving the signal with a 2D gaussian that spreads the
| intensity out to neighboring pixels). If we know that PSF
| specific details, we can deconvolve the image, either
| computationally, or by modifying the mirror in real time.
|
| From my understanding, you can project a laser into the
| atmosphere, where it gets affected by the PSF. When you look
| at that laser projection, you can find the PSF (because you
| know the input shape of the laser, and what it looks like
| after being affected by the PSF), and therefore use that in
| real time to deconvolve the astronomic images you are
| collecting.
|
| This process can be done so quickly it can adapt to immediate
| changes in the atmosphere (turbulence). "Enhance" is
| definitely a thing- it's widely used in both telescopes and
| microscopes (and if you had the right priors for a blurry
| photo, you could do it there too).
|
| I think this is a relatively simple read:
| https://en.wikipedia.org/wiki/Laser_guide_star along with
| https://www.llnl.gov/article/44936/guide-star-leads-
| sharper-...
| bloopernova wrote:
| The ever-changing surface of so many planets leads me to wish we
| had satellites in orbit around as much as possible. I'd love to
| read the "weather report" for Io or Titan!
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