[HN Gopher] NASA to launch space observatory that will map 450M ...
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       NASA to launch space observatory that will map 450M galaxies
        
       Author : gmays
       Score  : 261 points
       Date   : 2025-03-08 00:07 UTC (4 days ago)
        
 (HTM) web link (www.nbcnews.com)
 (TXT) w3m dump (www.nbcnews.com)
        
       | FirmwareBurner wrote:
       | _> four suitcase-sized satellites _
       | 
       | Americans will use anything else but the metric system :)
        
         | schainks wrote:
         | Hey! I know exactly how many Stanley cups fit in four
         | suitcases, you don't have to tell me twice.
         | 
         | </s>
        
         | malfist wrote:
         | Wait, is this carry on sized or checked size?
         | 
         | Is it delta's size limits, or are we following united or
         | American Airlines? Or heaven forbid, alligent?
        
         | niwtsol wrote:
         | The PUNCH mission features four 140-pound small satellites,
         | each about 1-by-2-by-3 feet in size.
         | 
         | Or
         | 
         | The PUNCH mission features four 63.5 kg small satellites, each
         | about 0.3048 m x 0.6096 m x 0.9144 m in size.
         | 
         | https://blogs.nasa.gov/spherex/2025/03/04/nasas-spherex-punc...
        
           | Ao7bei3s wrote:
           | About 30x60x90cm in size.
        
       | shmageggy wrote:
       | This is so cool, but I did not see a key piece of info in the
       | article: does the ongoing operation of this mission fall under
       | NASA's science budget and therefore at risk of cuts and defunding
       | under Trump [1]?
       | 
       | [1] https://arstechnica.com/space/2025/03/white-house-may-
       | seek-t...
        
         | ddon wrote:
         | Yep, it looks like it will be cut and closed, which is truly
         | unfortunate. It's disappointing to see that science nor
         | innovation are not a priority for this administration. And this
         | doge cutting of funding or even shutting down important
         | projects will have long-term consequences, impacting research,
         | education, and technological advancements that benefit
         | everyone.
        
           | bpodgursky wrote:
           | This is a proposal (not final) budget to be sent to congress.
           | What congress eventually allocates is what matters.
        
             | jeffgreco wrote:
             | Not according to the current presidential administration.
             | Impoundment is their stated goal.
        
         | connicpu wrote:
         | This one is planned to launch on Falcon so I wouldn't be too
         | surprised if it's one project the administration spares.
        
           | indoordin0saur wrote:
           | Everything launches on a Falcon these days. No one else can
           | catch up in terms of safety cost or speed.
        
             | gibolt wrote:
             | SpaceX is going to pass whatever company is launching
             | Falcon in short order, leaving them in the dust
        
               | niwtsol wrote:
               | The Falcon 9 is a SpaceX rocket
        
             | numpad0 wrote:
             | I'm not sure how to make out of comments like this. Is
             | SpaceX actually launching customer payloads under $50m or
             | whatever? Because, unless they are, it won't be long before
             | JAXA/MHI starts selling H3 at half the cost of H-IIA, which
             | is already like 15t to LEO for $67m at 150 JPY/USD, which
             | leaves F9 _reusable_ barely competitive in price. I don 't
             | know what India or China charge for foreign customers, but
             | is it really reasonable to expect worse deal than
             | Mitsubishi from them? ...
             | 
             | Superheavy-Starship reusable launches at F9 price _would_
             | completely destroy everything in space space, but so far
             | the only things it had disrupted are itself and airline
             | services under its flightpath. And even F9 is starting to
             | show increasingly clear signs of repetitive  "old space"
             | scrubs as NASA gets more disrupted.
             | 
             | Is that really a meaningful statement that stands, or it
             | that just hand wavy glance away one now?
        
               | indoordin0saur wrote:
               | > Is that really a meaningful statement that stands, or
               | it that just hand wavy glance away one now?
               | 
               | The $67m figure is the same one I'm finding for Falcon 9
               | (and it can carry loads 40% heavier). That made me think
               | they were matching each other on price to stay
               | competitive in the market and that seems correct as the
               | internal costs I'm seeing for SpaceX Falcon 9 launches
               | are estimated around $15mil, meaning they have a large
               | margin from which to come down from.
               | 
               | > it won't be long before JAXA/MHI starts selling H3 at
               | half the cost of H-IIA
               | 
               | SpaceX doesn't stand still. It's weird to think that in
               | several years SpaceX will be in the same place (relying
               | on Falcon 9) yet JAXA, etc will have improved
               | dramatically.
        
               | numpad0 wrote:
               | > SpaceX doesn't stand still.
               | 
               | So are they launching F9 at $67m? Or do you merely
               | _expect_ SpaceX to _eventually_ price match? Not that MHI
               | is selling a lot of slots, but still. Quoted payload
               | figures is also within ballparks.
        
               | indoordin0saur wrote:
               | They are actually doing launches as low as $62 million
               | (as of 2024). They also have enormous margin to lower
               | this cost because even the _upper-bound_ estimate by
               | industry analysts on the Falcon 9 launch cost for SpaceX
               | is only $28 million.
               | 
               | Source: https://spaceinsider.tech/2024/07/31/ula-vs-
               | spacex/#elemento...
        
               | panick21_ wrote:
               | I'm sorry no, you should spend some time actually
               | understanding the industry.
               | 
               | JAXA builds a tiny amount of rockets, almost exclusively
               | for their own use. They have never been a significant
               | player and its very unlikely that will change anytime
               | soon.
               | 
               | Its pure fantasy to suggest otherwise. And even if they
               | could reliably hit these prices at commercial launch
               | scale, Falcon 9 could easily lower their prices if real
               | competitors actually existed.
               | 
               | If H3 was such a dynamic thread as you suggest, why did
               | Amazon not buy 100s of launches from them. They bought
               | launches from every SpaceX competitor, but not Japan.
               | 
               | > I don't know what India or China charge for foreign
               | customers, but is it really reasonable to expect worse
               | deal than Mitsubishi from them? ...
               | 
               | China isn't really relevant. Western stuff is just not
               | going to fly from China.
               | 
               | India used to do more commercial stuff, but SpaceX
               | Rideshare is far, far, far more popular.
               | 
               | The reality is, India large rockets, like Japan, is
               | mostly build for their own program, they don't really
               | have that much access capability.
        
             | jajko wrote:
             | Costs are largely meaningless when talking about global
             | situation and other nations and their strategic interests.
             | Europe will move fully to ESA for anything actually
             | important, China and India have their own stuff too.
             | Private satellites, sure why not if companies are OK with
             | risking of getting their payload removed at last minute
             | because somebody again bruised musk's ego.
             | 
             | Business can't be done in an environment with zero trust,
             | doesn't matter how much better the offer looks on paper.
             | That trust with spacex is gone for good.
        
               | indoordin0saur wrote:
               | > Costs are largely meaningless
               | 
               | Costs are never meaningless when you're talking about
               | technical projects that cost billions of dollars.
               | 
               | > trust with spacex is gone for good.
               | 
               | Sorry to pop your bubble, but they launched 134 rockets
               | with payloads last year and they all made it to their
               | orbits successfully except for one of their own starlink
               | payloads. This is more than 90% of all launches that
               | occurred last year.
        
               | thinkcontext wrote:
               | > 90%
               | 
               | You mean 50%, there were 253 successful orbital launches
               | last year
               | 
               | https://en.m.wikipedia.org/wiki/2024_in_spaceflight
        
           | kelnos wrote:
           | Sure, the launch will go through, but SpaceX doesn't see any
           | recurring revenue from later operations, and I wouldn't put
           | it past the current administration to cut NASA's budget such
           | that continuing operations are affected.
        
         | ImJamal wrote:
         | Trump created the Space Force so he will presumably want some
         | amount of funding for rockets and what not. If Space Force
         | fails it would make him look bad after all.
        
           | andsoitis wrote:
           | Notwithstanding what you said, it is worth noting that the US
           | Space Force has been a long time in the making:
           | https://en.wikipedia.org/wiki/United_States_Space_Force
        
             | ImJamal wrote:
             | Trump is the one who actually decided to go through with
             | the creation of a distinct branch rather than having it as
             | a command. I think it is fair to say he created it.
             | 
             | There are all sorts of politicians and military members who
             | advocate for a distinct Cyber branch of the military
             | instead of Cyber Command. If a politician ends up doing
             | that, then he should get credit for creating it even though
             | it has been a long time coming.
        
               | mmooss wrote:
               | > distinct Cyber branch of the military instead of Cyber
               | Command
               | 
               | It's not 'instead', it's adding a cyber branch to a
               | different org chart. There are two major org charts in
               | the US military:
               | 
               | The services, such as Army, Navy, Space Force, etc.,
               | which are generally defined by domain (land, sea, orbit)
               | and whose role is to recruit, organize, train, and equip
               | forces - to prepare them, but not to deploy or command
               | them in operations.
               | 
               | The combatant commands, which are defined by geography -
               | such as Africa Command, Indo-Pacific Command - and
               | sometimes by geography-independent domains, such as as
               | Space Command or Cyber Command. The combatant commands
               | deploy the resources provided by the services in various
               | combinations. Modern conflicts generally require
               | resources from multiple services/domains working
               | _jointly_.
               | 
               | It makes some sense - you want domain experts to train
               | and equip them for their domain, then you must
               | necessarily deploy them jointly. Who should organize,
               | train, and equip sea-born forces? Probably you want the
               | Navy to do that, not the Army. Who should organize,
               | train, and equip electronic domain forces (I hate the
               | term 'cyber')? Do you want your IT organization
               | organized, trained, and equipped (think of the importance
               | of each step) by the US Marine Corps, or maybe by some
               | actual researchers, engineers, and experienced managers?
        
           | kelnos wrote:
           | That really has nothing to do with whether or not operations
           | for this project will be funded over the next several years.
        
         | eleveriven wrote:
         | That's a good question. Given how frequently NASA's science
         | budget gets caught in political crosswinds, it's definitely a
         | concern
        
       | dylan604 wrote:
       | "The SPHEREx mission <snip> will map the entire sky four times
       | over two years, offering scientists a chance to study how
       | galaxies form and evolve, and providing a window into how the
       | universe came to be."
       | 
       | So each object will be scanned ~6 months from the previous scan.
       | How much evolving within the universe will be noticeable within
       | that 2 year run? My gut response is not much, but that's why we
       | do the science to see the changes.
       | 
       | "designed to map the celestial sky in 102 infrared colors "
       | 
       | So I'm guessing the coolant used to make IR scanning possible
       | will be the limiting factor on operational time span. This
       | article didn't say where this satellite will be parked either,
       | but wikipedia[0] shows it to be a geosync orbit. Would have been
       | interesting to be able to design a replaceable coolant module to
       | extend the observations to really make seeing the evolution
       | possible. Obviously complexity adds to cost and design time, so
       | of course they didn't. Just dreaming
       | 
       | As an example, the study of the stars orbiting around SagA* are
       | very revealing, but have required > 10 years of observations.
       | 
       | [0] https://en.wikipedia.org/wiki/SPHEREx
        
         | perihelions wrote:
         | They're talking about galaxy evolution in the early universe,
         | over timescales of millions of years. Statistics measured
         | across the (large) sample group, not within one galaxy. Scroll
         | down to _" It will classify galaxies according to redshift
         | accuracy..."_
        
           | nashashmi wrote:
           | Right, at that scale, For a galaxy to move a fraction of a
           | centimeter will take a thousand years. So not much will be
           | missed in a gap of 6 months.
        
             | queuebert wrote:
             | This is nonsensical. Do you mean a tiny movement in the
             | field of view, which should be measured in angular
             | distance?
             | 
             | Or do you mean actual motion through the universe, in which
             | case the galaxies are moving at hundreds of kms per second,
             | which means they would move billions of kms in 6 mos.
        
               | nashashmi wrote:
               | Yes, field of view. I am considering 1 cm to mean 2-3
               | light years.
        
         | Sanzig wrote:
         | Why would coolant be a consumable? These things are usually
         | cooled with Stirling cryocoolers which are closed systems.
        
           | perihelions wrote:
           | I did a quick search and it seems there is neither?
           | 
           | - _" SPHEREx relies on an entirely passive cooling system --
           | no electricity or coolants are used during normal
           | operations"_
           | 
           | https://www.jpl.nasa.gov/news/6-things-to-know-about-
           | spherex...
           | 
           | edit to add:
           | 
           | - _" The telescope is passively cooled to below 80 K in low-
           | Earth orbit by three nested V-groove radiators. An additional
           | radiator cools the long wavelength focal plane temperature
           | below 60 K to reduce detector dark current."_
           | 
           | https://arxiv.org/abs/2404.11017v1
        
             | dylan604 wrote:
             | The Spitzer used passive cooling, but only as a method to
             | reduce the amount of coolant required. It still needed a
             | coolant.
             | 
             | "One of the most important advances of this redesign was an
             | Earth-trailing orbit.[1] Cryogenic satellites that require
             | liquid helium (LHe, T [?] 4 K) temperatures in near-Earth
             | orbit are typically exposed to a large heat load from
             | Earth, and consequently require large amounts of LHe
             | coolant, which then tends to dominate the total payload
             | mass and limits mission life. Placing the satellite in
             | solar orbit far from Earth allowed innovative passive
             | cooling. The sun shield protected the rest of the
             | spacecraft from the Sun's heat, the far side of the
             | spacecraft was painted black to enhance passive radiation
             | of heat, and the spacecraft bus was thermally isolated from
             | the telescope. All of these design choices combined to
             | drastically reduce the total mass of helium needed,
             | resulting in an overall smaller and lighter payload,
             | resulting in major cost savings, but with a mirror the same
             | diameter as originally designed. This orbit also simplified
             | telescope pointing, but did require the NASA Deep Space
             | Network for communications"[0]
             | 
             | [0]https://en.wikipedia.org/wiki/Spitzer_Space_Telescope
        
             | perihelions wrote:
             | I found an explanation of the "v-groove" radiator geometry,
             | if anyone else was curious about it:
             | 
             | (.pdf) https://ttu-
             | ir.tdl.org/server/api/core/bitstreams/71aee1e9-3...
        
           | dylan604 wrote:
           | Every system I'm familiar with that used liquid nitrogen to
           | cool the IR instruments has had a operational lifespan based
           | on the coolant. JWST is one such. "The coolant will slowly
           | vaporize, limiting the lifetime of the instrument from as
           | short as a few months to a few years at most."[0]
           | 
           | [0]https://en.wikipedia.org/wiki/James_Webb_Space_Telescope
        
             | perihelions wrote:
             | You've misread your source article--what you've quoted is
             | not a description of Webb.
        
               | dylan604 wrote:
               | Does that really change anything?
        
               | kadoban wrote:
               | Well, it doesn't apply to either JWST or the subject of
               | the article, so kind of feels like it's worth mentioning.
               | 
               | It doesn't change your specific, exact point (about
               | previous cooling systems you were aware of), but it makes
               | the conversation a lot less likely to confuse people IMO.
        
           | jessriedel wrote:
           | As another comment mentions, SPHEREx is passively cooled. But
           | fwiw, plenty of infrared space telescopes use consumable
           | coolant:
           | 
           | > Notable infrared missions that carried consumable cryogen
           | include IRAS (1983), ISO (1995-1998), Spitzer (2003-2009 in
           | cryo mode), Herschel (2009-2013), WISE (2009-2011 in cryo
           | mode), and Planck (2009-2013). Each relied on a finite liquid
           | helium (or solid hydrogen) supply to keep detectors cold and
           | reverted to a warmer operating mode or ended once their
           | coolant was depleted.
        
             | perihelions wrote:
             | Notably those were all far-infrared telescopes, which need
             | even lower temperatures (liquid helium) to escape thermal
             | noise.
        
         | niwtsol wrote:
         | To answer three of your questions:
         | 
         | - It is passively cooled rather than using an expendable
         | coolant- "SPHEREx relies on an entirely passive cooling system
         | -- no electricity or coolants are used, simplifying the
         | spacecraft's design and operational needs."
         | 
         | - It is a Medium-Class Explorers (MIDEX) mission -
         | Investigations characterized by definition, development,
         | mission operations, and data analysis costs not to exceed $180
         | to $200 million total cost to NASA. I think the cost of ground
         | support eats into the budget length. The original estimate for
         | project was $241M, so it was a large MIDEX
         | 
         | - It is in a Polar orbit around Earth at the day-night
         | (terminator) line
         | 
         | https://www.jpl.nasa.gov/press-kits/spherex/
         | 
         | https://explorers.gsfc.nasa.gov/missions.html
         | 
         | https://spaceflightnow.com/2019/02/14/nasa-selects-mission-t...
        
           | dylan604 wrote:
           | ah, I misread the Orbital Parameters on the wiki. that day-
           | night orbit is also a LEO which makes it even more possible
           | to do a manned mission for upgrades. Oh, wait, we no longer
           | have a shuttle for those types of missions.
        
             | nine_k wrote:
             | Even a Dragon could bring enough hardware and a crew for a
             | small upgrade or repair (to say nothing of the upcoming
             | Starship).
        
               | ericcumbee wrote:
               | Dragon lacks a Remote Manipulator System (Robot Arm) and
               | a airlock. things that make servicing objects in space a
               | lot easier. Im sure somewhere at NASA or SpaceX there is
               | rough set of specs on what a shuttle like starship would
               | look like complete with payload bay, robot arm, and eva
               | airlock.
        
               | IncreasePosts wrote:
               | The complete specs of the arm may now belong to a hostile
               | nation.
        
               | totetsu wrote:
               | https://en.m.wikipedia.org/wiki/Canadarm#
        
               | Frederation wrote:
               | A nation pushing back against the morons in Washington.
               | 
               | Hardly hostile. Unless you poke the bear.
        
               | dylan604 wrote:
               | If you're alluding to Russia, they've had them. They even
               | failed in making their version of a shuttle. With what
               | money would they do anything with now?
               | 
               | If you're alluding to China, they probably had the data
               | from the Russians anyways.
               | 
               | Otherwise, I'm out of guesses to your vagueness.
        
               | taggart wrote:
               | Canada built the shuttle arms:
               | https://en.m.wikipedia.org/wiki/Canadarm
        
               | sillywalk wrote:
               | > They even failed in making their version of a shuttle.
               | 
               | Nitpick: It was sort of successful. They built a shuttle,
               | and it successfully flew a single (un-crewed) mission of
               | a couple orbits. The collapse of the USSR / lack of
               | funding killed it.
        
               | vkou wrote:
               | It's amazing how all it takes is a few threats of
               | annexation, and for GOP thought-leaders like Ben Shapiro
               | to start talking about enslaving you[1] to work on the
               | Panama Canal to make another country rethink its
               | relationship with you.
               | 
               | Absolute animals. As is anyone else carrying water for
               | these politics. _There 's no excuse for it._
               | 
               | If you had anything at all to do with putting these
               | clowns in power - _reign them back in_. They are supposed
               | to work for you. Remind them of this.
               | 
               | [1] https://x.com/benshapiro/status/1876800394900152483?l
               | ang=en
        
               | nine_k wrote:
               | Sorry, "rein them in". Reign is about royal power; rein
               | is about controlling a horse. And we definitely don't
               | want any monarchs here.
        
               | nick12r55t1 wrote:
               | Can dragon launch to a polar orbit and safely deorbit
               | from a polar orbit?
        
               | perihelions wrote:
               | https://en.wikipedia.org/wiki/Fram2
        
             | mturmon wrote:
             | Remember, it is passively cooled (a major design plus and,
             | I assume, part of why it was able to achieve the cost it
             | did). So there would be no need for a manned mission. And
             | in fact, at that cost, it wouldn't make sense anyway.
        
           | pklausler wrote:
           | Possibly stupid question: how does this polar orbit _stay_
           | over the terminator? And how is the terminator defined for a
           | polar orbit here, since both the north and south poles are on
           | the terminator only at the equinoxes?
        
             | sbierwagen wrote:
             | >how does this polar orbit stay over the terminator?
             | 
             | Because it's launched at a angle _greater_ than a straight
             | north-south 90 degree orbit, so orbital precession will
             | correctly follow the terminator. Depending on the orbital
             | altitude this can be more than 140 degrees:
             | https://en.wikipedia.org/wiki/Sun-synchronous_orbit
        
         | pixl97 wrote:
         | >How much evolving within the universe will be noticeable
         | within that 2 year run?
         | 
         | Anton Petrov had a recent episode about rapid transformations
         | in large supergiant stars, so there are some parts of space
         | that can rapidly evolve.
         | 
         | https://www.youtube.com/watch?v=gHvV9ewPY7s
        
         | computerex wrote:
         | Thank you for awesome information!
        
         | mturmon wrote:
         | A nearby (excellent) comment
         | (https://news.ycombinator.com/item?id=43338459) gives further
         | context, but: the 6-month revisit period is just an artifact of
         | the Earth-orbit-based sky scanning strategy. In 6 months the
         | satellite, precessing at 1 degree/day, and facing away from the
         | sun during data collection, will scan the sky completely. (See
         | Fig 1 of the paper [0]).
         | 
         | So in particular, the 6-month period is not to revisit these
         | distant galaxies more than once to observe spectral changes.
         | The strategy, indeed, is to "stack" the multiple exposures to
         | beat down noise. (Fig.6 of [0], top left).
         | 
         | It is possible that they have designed the system so that it
         | could produce "just good enough" results in 6 months, with one
         | complete scan. This is called a "threshold mission" and it
         | would only be described in the full proposal.
         | 
         | I looked through the rest of the science cases (which are
         | secondary to the driving case of this mission), and none of
         | them seem to be reliant on revisits. (But open to correction on
         | this.)
         | 
         | [0] https://arxiv.org/pdf/1412.4872
        
           | JKCalhoun wrote:
           | Any chance there will be enough "parallax" in the 6-month
           | period to get a stereo-distancing map for the galaxies? Or do
           | we already have that from red-shift, relative luminance or
           | some other means?
        
             | perihelions wrote:
             | Andromeda (the nearest) is 2e19 km away and has a relative
             | motion of 300 km/s in the radial direction. If we assume
             | the tangential motion is similar, that's 5e9 km of
             | tangential displacement over 6 months, for a total angular
             | displacement of 5e-5 arcseconds (50 microarcseconds).
             | 
             | That's well below the precision of every telescope.
             | (Admittedly GAIA, the one designed for parallax
             | measurements, comes close, but its techniques only work on
             | very bright point-source objects).
             | 
             | I think these articles answer your question:
             | 
             | https://en.wikipedia.org/wiki/Cosmic_distance_ladder
             | 
             | https://news.ycombinator.com/item?id=43151943 ( _" Part two
             | of Grant Sanderson's video with Terry Tao on the cosmic
             | distance ladder (mathstodon.xyz)"_, 99 comments)
        
         | DiogenesKynikos wrote:
         | Most things astronomers observe do not change much over the
         | course of 6 months. For comparison, it takes the Sun about 200
         | million years to orbit around the center of the Milky Way once,
         | so a galaxy like the Milky Way would hardly change in 6 months.
         | 
         | However, there is an entire field of astronomy, called "time-
         | domain astronomy," that deals with things that do change on
         | human timescales. There are pulsating stars, supernovae,
         | galaxies with rapidly accreting central black holes, and many
         | other types of objects. Surveys that focus on the "time domain"
         | have survey strategies that are tailored to whatever type of
         | object they're looking at. For example, if you're looking for
         | planets that transit in front of their host stars, you should
         | look every ~30 minutes or so, because planet transits only last
         | around that amount of time.
        
       | ChuckMcM wrote:
       | It always surprises me how my enthusiasm for scientific discovery
       | is affected by fears of a dystopian future. My understanding is
       | that with red shift calibration here we'll get a much better idea
       | of the 'when' in terms of various galactic structures emerged,
       | that might give us an interesting idea of where we are in the
       | life-cycle of the Milky Way. But the observation of water
       | signatures will be the most interesting to me. Presumably there
       | is a _lot_ of water tied up in comets and such, but will SPHERE
       | be able to detect those signatures near planets?
        
         | turtletontine wrote:
         | The galactic and extragalactic science cases (meaning, "stuff
         | in the Milky Way" vs "everything inside the Milky Way") are
         | actually pretty unrelated here.
         | 
         | We actually have quite a good idea about the history of the
         | Milky Way and all the smaller galaxies that it's eaten (and
         | will eat, such as our main current satellites the Small and
         | Large Magellanic Clouds). We're even pretty sure that the MW
         | merged with another large galaxy about 11bil year ago,
         | sometimes called "Kraken"
         | https://en.wikipedia.org/wiki/Kraken_galaxy?wprov=sfti1.
         | SPHEREx is not interested in any of that, and it looks like
         | it's galactic science will mostly be mapping out where clouds
         | of ice crystals are in the Milky Way. SPHEREx has very low
         | spatial resolution (about 6 arcsec), so it's certainly not
         | observing any exoplanets, but that's the trade off with an all-
         | sky mission like this.
         | 
         | One of the big drivers of the extragalactic science, though, is
         | looking for signatures of cosmic inflation in the distribution
         | of galaxies on large scales. IMO this is by far the most
         | interesting science case, and will be genuinely exciting and
         | novel. Its survey design doesn't give it great resolution, but
         | it's amazing IR spectrophometry will let it map the rough
         | distribution of galaxies at redshifts we haven't been able to
         | survey before. This is called intensity mapping
        
         | tiborsaas wrote:
         | I can't really get what you meant by "dystopian future" in this
         | context. In my understanding that is a human caused concept.
        
           | JKCalhoun wrote:
           | Hard for me to parse as well -- but I think OP is talking
           | broadly about humans being able to keep our shit together
           | long enough to be able to reach other solar systems before we
           | outgrow our own.
        
         | eleveriven wrote:
         | As for water detection, I'd imagine SPHEREx will be better
         | suited for large-scale mapping rather than pinpointing water on
         | specific planets
        
       | layer8 wrote:
       | The Wikipedia article has more useful information:
       | https://en.wikipedia.org/wiki/SPHEREx
        
       | dj_gitmo wrote:
       | Do these missions ever build back-up hardware? What if the probe
       | is lost because of a lunch mishap, or there is a malfunction
       | during the deploy (see Viasat VS3 antenna deploy failure).
       | 
       | It is an added cost, but it cannot be that much compared to the
       | overall R&D/tooling/launch/ect cost.
        
         | kelnos wrote:
         | > _What if the probe is lost because of a lunch mishap_
         | 
         | Well, hopefully the people who are building the probe aren't
         | eating their lunches on top of it.
         | 
         | (Yes, I know. Fun typo nonetheless.)
        
         | mandevil wrote:
         | Into the 1970's, NASA did that. That was why there was Viking 1
         | and 2, Voyager 1 and 2, Pioneer 10 and 11, etc. Since then,
         | however, NASA has stopped doing that. It became a balancing
         | act- yes, 0 to 1 is much more expensive than 1 to 2, (1 to n is
         | not quite as cheap as it is with software but it's still much
         | cheaper than 0->1), but NASA Science is in the business of
         | answering questions. The question is, will building, launching,
         | and operating (the expensive part) two Parker Solar Probe's and
         | two Juno's answer more questions than building one Parker Solar
         | Probe, one Juno, and one OSIRIS-Rex? Almost certainly the three
         | different probes answers more questions than two copies of two
         | different probes. So once launch vehicle reliability got to be
         | good enough that the fear of total mission failure went down
         | low enough (1), duplicate missions basically went away.
         | 
         | 1: Edited to add: this is actually tied into the Space Shuttle
         | in interesting ways. See T.A. Heppenheimer, _The Space Shuttle
         | Decision_ for why the STS became the sole space launch system
         | for all of the US Government. Of course if it's manned it's
         | reliability has to be so high that you don't have to worry
         | about loss of payload, so building two copies of it was no
         | longer necessary.
        
           | dj_gitmo wrote:
           | Great answer.
           | 
           | > Of course if it's manned it's reliability has to be so high
           | that you don't have to worry about loss of payload, so
           | building two copies of it was no longer necessary.
           | 
           | I wasn't expecting a space shuttle tie in, but of course
           | there would be. They sure had to promise a lot to get that
           | thing off the ground.
        
       | alfiedotwtf wrote:
       | To be honest, I was expecting Elon and DOGE to have completely
       | gutted NASA by now, while at the same time allocating more
       | contracts to SpaceX.
        
         | dylan604 wrote:
         | I'd imagine he's currently more focused on FAA to get them off
         | his back about Starship issues.
         | 
         | Awarding new contracts doesn't require gutting NASA first, so
         | he can get to it later once the FAA has bent the knee
        
         | dakr wrote:
         | They're working on it. NASA HQ has already cut their "Office of
         | the Chief Scientist" (among others) and the current proposal is
         | to cut 50% of the science budget (which would effectively kill
         | it, it's already been squeezed).
        
         | d--b wrote:
         | This is a SpaceX contract
        
           | apawloski wrote:
           | The launch vehicle is SpaceX, but the science and mission
           | operations are NASA/JPL.
        
             | BHSPitMonkey wrote:
             | And to add to that, DOGE has been known to cancel contracts
             | where the money has already been paid (so we're effective
             | paying for nothing); SpaceX already has what it needs from
             | this contract and has nothing to lose by cancelling the
             | mission now.
        
           | dylan604 wrote:
           | SpaceX might be the one that takes it to orbit, but that's
           | the end of their involvement. It would be one of the NASA run
           | locations that would be controlling the craft, receiving the
           | data, analyzing the data, etc. The JWST is not a French
           | contract just because it caught a ride on an Ariane rocket.
           | 
           | To call that a SpaceX contract is a very myopic view.
        
       | metalman wrote:
       | 450M is somewhere between .1% and 0 % of the total number of
       | galaxies in the observable universe, so I am laying claim to 50,
       | galaxies, which is hopefully a full set of galaxie types, but
       | with a little haggling and trading, buying and selling galaxies I
       | can figure that out later. My Mom says as a child she sent away
       | and got title to one sqare inch of the moon, but it was a much
       | smaller universe then, especialy before inflation.
        
         | eleveriven wrote:
         | Imagine the value after cosmic inflation kicks in
        
       | eleveriven wrote:
       | It's pretty incredible to think that we're at a point in human
       | history where we can map 450 million galaxies and probe the
       | origins of the universe
        
         | Tepix wrote:
         | The Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging
         | Survey has recorded more than one billion galaxies.
         | 
         | But there are _many_ more galaxies in the observable universe
         | ... somewhere between 2 and 20 trillion
        
           | jajko wrote:
           | > But there are many more galaxies in the observable universe
           | ... somewhere between 2 and 20 trillion
           | 
           | A bit less officially, need to remove one zero [1]
           | 
           | [1] https://en.wikipedia.org/wiki/Galaxy#:~:text=It%20is%20es
           | tim...
        
             | Tepix wrote:
             | There are more recent estimates going from 6-20 trillion
             | now: https://bigthink.com/starts-with-a-bang/galaxies-in-
             | universe...
        
               | hnuser123456 wrote:
               | That article is going beyond the observable universe,
               | other comments were talking about within it.
        
         | jimkleiber wrote:
         | I feel infinitesimally small.
        
           | igleria wrote:
           | me too, but big things have small beginnings!
        
         | JKCalhoun wrote:
         | And to think I assumed Astronomy was a stagnant field some
         | decades ago. I have no idea why I thought that. Maybe that
         | optical resolution from ground-based telescopes was not going
         | to advance orders of magnitudes? Maybe I didn't think the
         | sciences would continue to get money for space telescopes?
        
           | DiogenesKynikos wrote:
           | Astronomy has been in a golden age for the last 35 years,
           | based on:
           | 
           | 1. Digital cameras, and the computers to analyze images.
           | 
           | 2. Space telescopes (Hubble Space Telescope, the first large
           | space telescope, only launched in 1990).
           | 
           | 3. The building of massive ground-based telescopes. Before
           | 1990, the largest telescope had a mirror diameter of 6
           | meters. Now, multiple 30-meter telescopes are under
           | construction. Collecting power goes with the square of the
           | diameter, so this is an increase of 25 times in collecting
           | power!
           | 
           | 4. Very recently, the development of gravitational-wave
           | interferometers, which allow astronomers to observe a totally
           | new type of radiation.
        
             | nuccy wrote:
             | To add to the list (the order is arbitrary):
             | 
             | 5. Advances in the multi-messenger observations, where
             | apart of photons and gravitational waves, astronomers can
             | detects also neutrinos with specialized neutrino detectors,
             | e.g.: IceCube [a], though there are many more of those [b].
             | 
             | 6. Advances in very-long-baseline interferometry [c] using
             | a globe-sized array of radio-telescopes, like Event Horizon
             | Telescope [d]
             | 
             | [a]
             | https://en.wikipedia.org/wiki/IceCube_Neutrino_Observatory
             | 
             | [b] https://en.wikipedia.org/wiki/Neutrino_detector or here
             | https://en.wikipedia.org/wiki/List_of_neutrino_experiments
             | 
             | [c] https://en.wikipedia.org/wiki/Very-long-
             | baseline_interferome...
             | 
             | [d] https://en.wikipedia.org/wiki/Event_Horizon_Telescope
        
               | hnuser123456 wrote:
               | And one more:
               | 
               | 7. The LISA mission is underway to build a space-based
               | detector for gravitational waves at the 0.1hz region,
               | whereas LIGO is sensitive around the 500hz region. 500hz
               | corresponds to inspiraling stellar mass black holes.
               | 0.1hz corresponds to inspiraling supermassive black
               | holes. Think about the most powerful subwoofer the laws
               | of physics allow, given the maximum amount of mass
               | density in a volume and the speed of light.
               | 
               | https://en.wikipedia.org/wiki/Laser_Interferometer_Space_
               | Ant...
        
       | nicholasbraker wrote:
       | "Space is big. You just won't believe how vastly, hugely, mind-
       | bogglingly big it is. I mean, you may think it's long way down
       | the road to the chemist's, but that's just peanuts to space."
        
       | arisAlexis wrote:
       | I call it here, Musk will cut it before they do it
        
         | keepsweet wrote:
         | I highly doubt it, but is that plausible?
        
       | perihelions wrote:
       | https://blogs.nasa.gov/spherex/2025/03/12/signal-acquired-na... (
       | _" Signal Acquired: NASA's SPHEREx Begins Science Mission"_)
       | 
       | Success!
        
       | ourmandave wrote:
       | Like the myth Inuit have 100 words for snow, how many words do
       | astronomers have for big?
        
       | foobarbecue wrote:
       | aquisition of signal! https://www.nasa.gov/news-release/nasa-
       | launches-missions-to-...
        
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       (page generated 2025-03-12 23:02 UTC)