[HN Gopher] What is Webb observing now?
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What is Webb observing now?
Author : janandonly
Score : 307 points
Date : 2024-04-12 07:29 UTC (15 hours ago)
(HTM) web link (spacetelescopelive.org)
(TXT) w3m dump (spacetelescopelive.org)
| gigatexal wrote:
| This is so very, very cool.
|
| I did hear some horrible news. Seems the funding for the next-gen
| (or even current maintainence of) Chandra-X ray observatory
| (space based telescope) won't get approved which is a huge shame.
|
| Maybe politicians could be persuaded by sites like these and
| greater awareness campaigns to not lose such a worthwhile
| instrument for science.
|
| And if it does is there an international equivalent maybe via the
| ESA or another that could make up for it or should the science
| world suffer because of the lack of US funding?
| system2 wrote:
| Politics and religion slowed down our space exploration by many
| thousands of years.
| thriftwy wrote:
| I... Don't think so?
|
| Soviet Union as a materially poor country will not pour so
| much money into exploring space if it wasn't so important
| politically at the moment.
|
| The US was much wealthier, but also skipped space spendings
| the first moment politics no longer persuaded space
| exploration.
|
| Stuff like GPS and especially Glonass were also borne out of
| political goals. Same for ISS.
|
| If anything, the only way we may get to explore solar system
| is via political push.
| Fremololni wrote:
| NASA asks for money and politicians say no.
| hunter-gatherer wrote:
| NASA often asks for money and politicians say yes.
| Fremololni wrote:
| Yes but that's not the criticism. It's the no saying
| jazzsouff wrote:
| The post WW2 cold war is what pushed our understanding of
| space. So actually modern politics helped with that.
| Cthulhu_ wrote:
| But once the space race to the moon was won - and all major
| powers had proven they are capable of producing ICBMs - it
| feels like the energy and financing just went out of it.
| There's no more political or military gain to be had from
| space exploration so governments only put in a token
| amount, and there's only limited commercial gain from e.g.
| telecom, mapping and navigation, but that's all focused on
| earth itself.
|
| There's no major financial incentive go to the moon or
| mars, other than would-be space tourists or colonists that
| are willing and able to pay for their own trip.
|
| The only way spacefaring could be commercialised is with
| asteroid mining, and that's a long way away still. The eye-
| popping "this asteroid could be worth a hundred trillian
| dollars!!1" kind of headlines are sensationalised to
| attract investors to fund exploration missions to figure
| out if the theory matches the practice, but even if it was
| worth that amount, getting any material back to Earth is
| currently cost- and engineering-prohibitive. It may become
| viable in our lifetime, for example if they can get a
| Starship sized craft there, fill the hold with titanium and
| return all of it to Earth, but that's a long way away
| still.
| Amezarak wrote:
| > There's no major financial incentive go to the moon or
| mars, other than would-be space tourists or colonists
| that are willing and able to pay for their own trip.
|
| I don't think there's any incentive at all. What reason
| is there for anyone to go to Mars other than to say they
| did, at _enormous_ expense and technical effort? Best
| case scenario, after spending tens of trillions of
| dollars, we 're able to build a base that needs continual
| resupply from Earth and in which you're basically living
| in a box - you'll never be able to set foot outside
| except in a suit, worse even than our Antarctic bases.
| And even then, we can expect long-term health effects.
| Well, you can live in a box on Earth.
|
| The reason there isn't major funding for space is because
| most people don't care all that much. It's a nice thing
| to have, and I wish more people did support increasing
| this sort of funding, but it's perfectly understandable
| why most people don't want to contribute significant
| percentages of GDP to a scifi dream.
| AlecSchueler wrote:
| We're not talking about a vanity Mars visit, we're
| talking about building an X-ray observatory. The JWST has
| already been phenomenal, it feels like it's delivering an
| almost daily barrage of discoveries, many of which are
| already affecting long standing understandings of the
| universe. The benefit of these projects is that they
| actually help us to answer the basic questions of
| existence in a way nothing else does.
| Amezarak wrote:
| Yes, as I said, I wish projects like this did have better
| funding, but the comment I was replying to mentioned
| going to the Moon or Mars.
| ziddoap wrote:
| While I mostly agree with what you've said in respect to
| a Mars base -- I think you are leaving out a critical
| benefit of these types of endeavors.
|
| The technology invented and/or adapted to facilitate
| these enormous space projects is very often applicable in
| other fields or daily life.
|
| Some examples from the past include metallic glass (now
| used in power plants), translucent polycrystalline
| alumina (now used in invisible braces), water
| purification technologies, the coatings used on launch
| pads was adapted for use in coating steel for high-rise
| building projects, etc. The list is quite long.
|
| There are hundreds of spin-off technologies, many of
| which are used daily, which originated from various
| ambitious space projects.
| wolverine876 wrote:
| > But once the space race to the moon was won - and all
| major powers had proven they are capable of producing
| ICBMs - it feels like the energy and financing just went
| out of it.
|
| Quite a few things have been done since then, including
| the JWST, all the other space telescopes, helicopters on
| Mars, visits to every planet in our solar system system,
| ...
| asdff wrote:
| It didn't end just at the ICBM of course or even the
| nuclear submarine. Satellite warfare became and is still
| a huge focus. Of course the public was pitched the
| maintenance bay of the space shuttle was to repair a
| peaceful satellite only. However, you can imagine how
| supremely useful it would be for a modern military to
| have the capability of deploying sappers and a workshop
| on any object in earth's orbit as well, which is what the
| space shuttle system also allowed for.
| iraqmtpizza wrote:
| science is just a spinoff of philosophy which was religiously
| motivated. what kind of drug-induced state do you have to be
| in to think that the Romans would have been flying around the
| Earth if only everyone thousands of years prior was magically
| a self-absorbed nihilist
| shigawire wrote:
| Rude phrasing, you shouldn't do that.
| olddustytrail wrote:
| Indeed, if they hadn't made the pyramids so heavy they could
| have been spaceships!
| sneela wrote:
| Zooming out, panning around, and seeing the milky is... jaw
| dropping in a way. I know it's silly because we've seen SO many
| photos of the universe, but I still get the goosebumps every time
| I think about it. And the detail too! You can _really_ zoom in.
|
| I tried to look for the moon, but it looks like it's not
| possible:
| https://old.reddit.com/r/askscience/comments/rwynmt/could_th...
| regularfry wrote:
| If I zoom in, I see a reddish mottled pattern. Is that sensor
| noise, background radiation, or something else?
|
| Similarly, if I zoom out to 30.39 angular degrees, there's a
| similar-ish green mottled pattern that's very prominent. What's
| that? It looks like it's got linear features, which might be a
| stitching artefact of some sort, maybe?
| regularfry wrote:
| This was the specific target at the time:
| https://spacetelescopelive.org/webb?obsId=01HTJT20C0STKNZ01K...
| jofer wrote:
| I'm not an astronomer, but I believe the "mottled red" features
| are distant objects that are redshifted. Note that they're
| almost all red no matter where you zoom in. That's the evidence
| that space is expanding in a nutshell.
| privong wrote:
| Distant objects do tend to look redder because of redshift,
| but the mottled pattern is a bit too regular to all be
| distant galaxies. It's more likely to be the noise in the
| data used for the red channel (likely the infrared Ks
| filter).
| privong wrote:
| > If I zoom in, I see a reddish mottled pattern. Is that sensor
| noise, background radiation, or something else?
|
| I assume you mean the pattern that is distributed across the
| general image? That's noise in one of the three filter images
| used to make the color image. 2MASS imaged in the J, H, and Ks
| filters (likely mapped to blue, green, and red, respectively).
| It could be that the choice of stretch is emphasizing the noise
| in that filter a bit more. Alternately, the noise there could
| be a bit higher (at the long wavelength end, Ks starts to cover
| a part of the spectrum where there's appreciable emission from
| a ~300K blackbody, i.e., the general temperature of things
| Earth).
|
| > Similarly, if I zoom out to 30.39 angular degrees, there's a
| similar-ish green mottled pattern that's very prominent. What's
| that? It looks like it's got linear features, which might be a
| stitching artefact of some sort, maybe?
|
| Perhaps regions where the image was made using only the H band
| from the 2MASS survey?
| andrewstuart wrote:
| So.... pretty much a game of Star Raiders?
|
| https://ia902205.us.archive.org/15/items/a8b_Star_Raiders_19...
| safety1st wrote:
| Quite fun. I was thinking it would be awesome to have whatever
| Webb is currently looking at as my desktop background or a
| website background or something. Glancing through the FF
| inspector it doesn't look like there is a single image which
| represents that, though. It looks like a piece of JS called
| Aladin is stitching together a bunch of 512x512 images. Anybody
| know more about this?
| andai wrote:
| I think most operating systems let you set a web page as your
| wallpaper... or they used to, at least.
|
| Not sure if there's a way to make this site load full screen by
| default though. And I don't know if the "desktop browser" can
| run user-scripts...
| _joel wrote:
| Heh, brought back memories of
| https://en.wikipedia.org/wiki/Active_Desktop
| alexpotato wrote:
| The other option is to use Chrome/Firefox headless mode and
| take a screen shot.
|
| You can probably then crop it automagically with some command
| line image tool to get you an image for your desktop.
| apawloski wrote:
| Not sure about JWST, but for Earth-observing satellite data
| it's common to store data in formats that support tiling and
| ranged reads so that clients are only loading the parts of the
| dataset relevant to current view.
|
| My guess is something similar is happening here on the other
| side of that library.
| alex_suzuki wrote:
| This is amazing. Anyone know if they have some kind of API access
| for the feed?
| Cthulhu_ wrote:
| There is https://github.com/avatsaev/webb-tracker-api which
| says it gets its info from
| https://www.jwst.nasa.gov/content/webbLaunch/whereIsWebb.htm...
| not sure if it's a content scraper or if there's an API there
| as well.
| syadegari wrote:
| +1!! This may sound weird, but I can use this as a mood booster
| when life gets tough. Side note: I might be biased because I also
| find it useful to think about the vastness space to trick my
| brain falling asleep (I watch a lot of video astronomy videos).
| RajT88 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."
|
| Per wikipedia:
|
| The observable universe contains as many as an estimated 2
| trillion galaxies and, overall, as many as an estimated 10^24
| stars - more stars (and earth-like planets) than all the grains
| of beach sand on planet Earth. The estimated total number of
| stars in an inflationary universe (observed and unobserved) is
| 10^100.
|
| IMO, a trillion is a number the human mind has trouble
| conceiving. We understand it only in an abstract sense - if you
| try to imagine what a trillion stars looks like in front of
| you, or a billion, or a million even, most likely you're
| imagining at best tens of thousands. 10^24 is orders of
| magnitude more abstract:
|
| 1,000,000,000,000,000,000,000,000
| bobbob1921 wrote:
| I have always found the analogy all the grains of sand on the
| beaches of earth to be something that helps accurately convey
| large numbers to myself and others. Somethings I've always
| wondered about this analogy:
|
| 1 - at what depth are they referring to, i.e. if you're at a
| beach and dig down two feet you're still Coming in contact
| with sand (and grains of sand). Do these count also?
|
| 2 - if you wade out into the ocean and go underwater, there
| are also more grains of sand under the water (are these
| included?). (what about all the grains of sand on the various
| vast deserts around earth?)
|
| For number two I would assume NO as the analogy says all the
| grains of sand on the earths beaches a beach.
| jajko wrote:
| As per parents numbers, its way way more than all the
| grains of sand _anywhere_ on Earth.
| syadegari wrote:
| Does someone know why the bright stars in the image do not show
| the hexagonal pattern that is present in published images of
| Webb?
| Cthulhu_ wrote:
| I presume it's not a live view of what Webb is seeing but
| existing images / visualisations from other sources pointing in
| the same direction Webb is right now.
| delecti wrote:
| My understanding is that the 6-pointed spike diffraction
| pattern only occurs on stars, and that the bright points
| without them are galaxies.
| privong wrote:
| The background image is not data from Webb; it is a near-
| infrared image from the 2 Micron All-sky Survey (2MASS). See
| @skybrian's comment:
| https://news.ycombinator.com/item?id=40013769
| chilling wrote:
| What a time to be alive!
| designium wrote:
| Indeed very cool I didn't know that you could watch them live!
| croes wrote:
| You can't
|
| https://news.ycombinator.com/item?id=40013769
| lnauta wrote:
| This is really cool. And having that skymap makes it so much
| better!
| 7373737373 wrote:
| I wish there was such an "attention map" for more telescopes
| skybrian wrote:
| I'm getting the impression that some people don't know what
| they're looking at. It says "Background: Two Micron All Sky
| Survey" which you can read about here [1]. This is _not_ a live
| image. It's just showing you where it's pointing, which isn't so
| meaningful for most of us. (It's random-looking stars.)
|
| You can read interesting details about the current observation at
| the top, though. Currently:
|
| * A census of high-redshift kpc-scale dual quasars
|
| * A 49 minute, 55 second observation.
|
| There's a link to the research proposal [2]
|
| Apparently it's a six-month survey of dual (possibly lensed)
| quasars. Gravitational lensing can cause magnification,
| distortion, and duplication of the image of whatever is behind
| it, so this is a way to learn more about very distant (early)
| quasars.
|
| A quasar is a supermassive black hole at the center of a galaxy,
| so this seems like a way to take lensed pictures of a lot of
| early galaxies?
|
| [1] https://en.m.wikipedia.org/wiki/2MASS [2]
| https://www.stsci.edu/jwst/science-execution/program-informa...
| ianburrell wrote:
| Webb won't ever provide a recent view since the images belong
| to the research group and are only made public when the results
| are released.
|
| Also, Webb can't provide a video feed since it is taking long
| exposures, and probably only sends results back to Earth when
| image is finished. The images are in the infrared and only look
| good when processed.
| basil-rash wrote:
| > only look good when processed
|
| Ehh. I personally can't stand all the post processing folks
| love to make their results look "magazine ready". I think the
| most minimal transformation possible to map the data into
| 0xRRGGBB would look the best, ideally with a simple
| standardized algorithm that doesn't allow for any "artistic
| license".
| _trampeltier wrote:
| IR pictures would be not RGB, just black/white (or whatever
| palette you like). But yes, it would be possible. For ex.
| from Flir Thermal cameras, you also can output the image
| just as spreadsheet. You can even choose the values as
| temperature (which is calculated) or just as energy (what
| the sensor gets).
| wang_li wrote:
| Light isn't RGB. We just receptors that react to certain
| wavelengths. I suspect the sensors on the telescope have
| a range of wavelengths they are sensitive to. It would be
| a straightforward translation to shift it to map it to
| the visible spectrum without varying the relative
| intensities to accentuate certain aspects of the image.
| Tagbert wrote:
| The IR may be in a very narrow band. The visible
| wavelengths have different colors because there are a
| range of wavelengths that correspond to different cones
| in our eyes that roughly match red:green:blue sensors. If
| you shift the IR frequency up into the visible range, you
| would just get a luminance image (like grayscale)
| centered on one visible wavelength like red.
|
| False color imaging sometimes applies colors to different
| luminance levels or sometimes it takes multiple images at
| different wavelengths and assigns RGB values to each of
| those wavelengths. The results are informative but
| require some editorial / aesthetic decisions to produce
| the best results.
| sneak wrote:
| I encourage you to try some raw file photography and
| processing. A bitstream from a sensor is not an image and
| there is no "correct" or "accurate" image from a captured
| signal.
|
| Think of it like using a linear or log scale for a chart
| axis: neither is "more correct", neither is taking
| "artistic license".
| basil-rash wrote:
| Poor example, given many photographs shoot raw precisely
| because it gives them more room for artistic decisions in
| post. Obviously the standardized algorithm should have
| basic factors like gamma and general phase shifting
| incorporated, but the idea of being able to adjust the
| maps delta between arbitrary adjacent inputs is of
| questionable benefit to the community. It's akin to
| adjusting levels via curves with many points, and it'd be
| incorrect to say folks are taking artistic liberties when
| they do that.
| asdff wrote:
| It would be nice if they stopped with the false color, and
| just scaled it to whatever color an astrounaut might see
| from that point of view.
| anamexis wrote:
| Given that these images are infrared, that wouldn't be
| much.
| mr_mitm wrote:
| Besides the wavelength being outside of human perception,
| an astronaut wouldn't see anything due to the low photon
| flux. These pictures have a very high exposure time.
| Tagbert wrote:
| just bring it up in an editor and drop the saturation to
| zero. That will take it back to a luminance map image.
| BurningFrog wrote:
| Everything Webb sees is infrared light, which is invisible
| to humans, so you _have_ to do some processing to make them
| look good.
| basil-rash wrote:
| Yes, that is what the map does. Convert values from one
| domain to another. That is the purpose of mapping. The
| point is to make it as simple and consistent as possible.
| tayo42 wrote:
| That's what they do already. Each wavelength that comes
| from different atoms gets a different color.
| __egb__ wrote:
| To expand on this, Webb uses the Deep Space Network (DSN) to
| communicate with us. It can't stream data back 24/7. There
| are generally three contacts per day each lasting a few
| hours, but I believe this is dependent on the scheduling of
| contacts with other missions that also use the DSN.
|
| Also, the science data that is sent back is a stream of
| packets from all the data that was taken since the last
| contact. The packets are arranged for efficient transmission.
| One of the first steps of the science data processing is to
| sort the packets into exposures. Often packets for an
| exposure are split among multiple SSR (which stands for
| solid-state recorder) files. Sometimes there are duplicate
| packets between SSRs (data sent at the end of a contact is
| repeated at the beginning of the next contact). Only when the
| processing code determines that all expected packets are
| present--by using clues from other subsystems--can the next
| step (creating the uncalibrated FITS) begin.
|
| If anyone is interested more details, the packet stuff is
| based on standards from the Consultative Committee for Space
| Data Standards
| (https://public.ccsds.org/Publications/BlueBooks.aspx).
| devwastaken wrote:
| Is it possible to put an antenna on a roof and capture this
| data?
| Retric wrote:
| Some of it, though no single location is always able to
| point in the right direction.
|
| The signal is also really weak coming from 30x the
| distance to geostationary orbit and setup for the DSN, so
| you need a large parabolic antenna.
|
| https://www.nasa.gov/directorates/somd/space-
| communications-...
| VyseofArcadia wrote:
| I know desktop widgets have been out of fashion for a while, but
| a desktop widget of this would be great. Or even just a simple
| XCoffee-style application.
| sentrysapper wrote:
| This is amazing. I navigated back to some previous targets and
| saw what looks like some kind of astronomical event, blue
| clusters lining up to some kind of explosion. Can anyone explain
| what Webb is seeing to the left of its target here?
|
| https://spacetelescopelive.org/webb?obsId=01HTJT20DRPEDT9DQN...
| Tempest1981 wrote:
| Hmmm, unfortunate timing:
|
| "Planned Outage - On Friday, April 12th starting at noon through
| Sunday, April 14th, Space Telescope Live may be unavailable. We
| apologize for any inconvenience."
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(page generated 2024-04-12 23:01 UTC)