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posted by janrinok on Saturday November 27 2021, @06:17AM   Printer-friendly

SpaceX's Starlink Will Make Life Hell for Astronomers Like Me. Telescopes on the Moon Could Help Fix That.:

This "mega-constellation" of Starlink satellites is the brainchild of Elon Musk's company SpaceX. Their plan is something straight out of science fiction: put 42,000 satellites into orbit, and broadcast wireless internet to anyone and everyone, all of the time. Early reviews have been... less than stellar ("unreliable, inconsistent, and foiled by even the merest suggestion of trees", said The Verge). But the tech will no doubt improve. Like it or not, ubiquitous Starlink internet is coming.

There's also no reason to think that SpaceX is the only player in town. A number of other companies and countries are all planning their own satellite mega-constellations, from Amazon (3,236 satellites as part of Project Kuiper), OneWeb, and Boeing, to China's ambitious plan for a 13,000-strong swarm.

Astronomers like myself have been less than enthusiastic about the prospect of a night sky full of artificial satellites. Our most sensitive telescopes are designed to pick up the unimaginably faint signals from planets orbiting distant stars, and galaxies billions of years in the past. How did the first galaxies form after the Big Bang? How fast is the universe expanding? Are there any dangerous asteroids that might crash into Earth? Having tens of thousands of satellites criss-crossing the sky and obscuring the view is going to make answering these questions more difficult.

This is going to be a serious problem for some future projects. The Vera C. Rubin Observatory is an upcoming telescope, located under Chile's dark skies, that will have the unprecedented ability to photograph the entire sky every few nights.

[...] It will also be severely impacted by satellite constellations. The telescope is sensitive enough to observe some of the faintest visible signals imaginable, with an extremely wide view of the sky. But that also means that satellite trails that cross its view show up as awful wide streaks that ruin the image. Up to a third of all the data taken by the telescope could be seriously affected, hampering its ability to study everything from near-Earth asteroids to the distant universe.

SpaceX has made some effort to dim their satellites—but even the new black-painted versions, called DarkSat, are still pretty bright (they "do not achieve the brightness goals recommended," according to the International Astronomical Union). And even if SpaceX plays nice with astronomers, the orbital gold-rush is only just getting started. We could have more than 100,000 satellites in orbit around Earth within the next 10 years.

[...] This is a tragedy: The sight of our universe, in all its splendor, is nothing less than a shared human birthright. But there are other worlds, and other skies. And the clearest, most pristine sky of all is waiting for us on the silent surface of the moon. We just need to take that one small step.


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  • (Score: 3, Insightful) by Anonymous Coward on Saturday November 27 2021, @06:27AM (3 children)

    by Anonymous Coward on Saturday November 27 2021, @06:27AM (#1199906)

    Now they're polluting space, and it will make our future there perilous. Micro sattelite swarms are basically a guarantee of future space junk.

    • (Score: 4, Insightful) by Anonymous Coward on Saturday November 27 2021, @08:47AM (2 children)

      by Anonymous Coward on Saturday November 27 2021, @08:47AM (#1199927)

      Micro-satellites are normally deployed to low orbits that decay quickly. Of the mega-constellation providers, SpaceX is the only one actually doing something about either the space junk problem or the astronomy problem. OneWeb simply don't care beyond the absolute minimum lip service the law requires of them. The PRC simply don't give a fuck, but articles like this won't have any effect on them either. (Kuiper isn't a problem because they aren't actually doing anything beyond taking up broadcast licence slots.)

      • (Score: -1, Offtopic) by Anonymous Coward on Saturday November 27 2021, @09:30PM (1 child)

        by Anonymous Coward on Saturday November 27 2021, @09:30PM (#1200060)

        Found the woman-hater. SpaceX's plans to blot out the night sky will disproportionately affect female astronomers. There is a huge shortage of female astronomers because of dudebros like the Musky One and their reckless disregard for female astronomy.

        Only the real men at Boeing will be able to deploy these satellites responsibly in a way that empowers female astronomers and engineers and honors the legacy of Vera Rubin.

        • (Score: -1, Flamebait) by Anonymous Coward on Saturday November 27 2021, @10:11PM

          by Anonymous Coward on Saturday November 27 2021, @10:11PM (#1200070)

          I see that the virgin mod-bomb squad is out in force today! These incel moderators will never get laid. They need to grow up and learn from Boeing how to treat ladies right. As a male feminist I've seen this so many times before, so many sad man-children who think equality means equality, or that smashing gender dichotomy gives men an excuse for being emotional, vulnerable weaklings. Can't they see how fragile women are? Male feminists like me get laid several times per day for the work we do keeping women safe. So sad that somebody would shirk off their duty towards women.

  • (Score: 3, Funny) by Frigatebird on Saturday November 27 2021, @06:37AM (2 children)

    by Frigatebird (15573) on Saturday November 27 2021, @06:37AM (#1199907)

    Only solution, all amateur astronomers need to switch from finder scopes or red-dot or Telradish devices, to full on, full power laser devices. Ones with enough power to gently nudge any capitalist internet provider out of its assigned orbit. If only I could do this on a terrestrial basis! Comcast, feel my photons!

    • (Score: 2) by sgleysti on Saturday November 27 2021, @06:10PM

      by sgleysti (56) Subscriber Badge on Saturday November 27 2021, @06:10PM (#1200016)

      Comcast, feel my photons!

      I mean, they are force mediating particles.

    • (Score: 2) by Freeman on Monday November 29 2021, @06:00PM

      by Freeman (732) on Monday November 29 2021, @06:00PM (#1200615) Journal

      The power of such a laser would likely get you in trouble.

      Favorite laser related random question and answer:
      https://what-if.xkcd.com/13/ [xkcd.com]

      Laser Pointer

      If every person on Earth aimed a laser pointer at the Moon at the same time, would it change color?
      —Peter Lipowicz

      Not if we use regular laser pointers.

      The first thing to consider is that not everyone can see the Moon at once. [...]

      --
      Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
  • (Score: 1, Insightful) by Anonymous Coward on Saturday November 27 2021, @07:03AM (22 children)

    by Anonymous Coward on Saturday November 27 2021, @07:03AM (#1199914)

    Once Starship is operational, it will be cheap enough to get to orbit that they can launch all the space telescopes they need. No need to put them on the Moon (unless you want to put one on the far side so you can be completely isolated from Earth) but just put them in a higher orbit than the communication satellites.

    • (Score: 3, Touché) by takyon on Saturday November 27 2021, @07:16AM (16 children)

      by takyon (881) <takyonNO@SPAMsoylentnews.org> on Saturday November 27 2021, @07:16AM (#1199918) Journal

      Starlink is part of SpaceX's evil plot to increase launch revenue by forcing ground telescopes to go into space.

      --
      [SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
      • (Score: 3, Insightful) by mhajicek on Saturday November 27 2021, @07:39AM (14 children)

        by mhajicek (51) on Saturday November 27 2021, @07:39AM (#1199920)

        May as well ban lights in the cities as well. Dark skies are pretty, who cares if lots of people have no reasonable internet options?

        /S

        --
        The spacelike surfaces of time foliations can have a cusp at the surface of discontinuity. - P. Hajicek
        • (Score: 1, Touché) by maxwell demon on Saturday November 27 2021, @07:48AM (13 children)

          by maxwell demon (1608) on Saturday November 27 2021, @07:48AM (#1199923) Journal

          Ever heard of that great invention called fibre-optic cable? Doesn't impact astronomy at all, and brings better internet than any satellite ever could.

          --
          The Tao of math: The numbers you can count are not the real numbers.
          • (Score: 2, Insightful) by Anonymous Coward on Saturday November 27 2021, @08:29AM (12 children)

            by Anonymous Coward on Saturday November 27 2021, @08:29AM (#1199926)

            A sizable chunk of the world's population will not ever have access to fibre. It is great in cities and suburbia, but the installation cost per foot quickly becomes prohibitive in rural areas, assuming you can even find anyone willing to lay it.

            • (Score: 1, Insightful) by canopic jug on Saturday November 27 2021, @08:47AM (4 children)

              by canopic jug (3949) Subscriber Badge on Saturday November 27 2021, @08:47AM (#1199928) Journal

              <sarcasm>It's almost like it is not possible to pool resources and elect representatives to apportion those resources in pursuit of common goals and good. Fortunately, there were already power lines and phone lines growing out of the ground all over the land and waiting in place so people could move there and build houses and businesses and just plug in. Maybe the fibre is already there and we just need to dig a few inches in the right place. </sarcasm>

              --
              Money is not free speech. Elections should not be auctions.
              • (Score: 2, Insightful) by Anonymous Coward on Saturday November 27 2021, @09:14AM (3 children)

                by Anonymous Coward on Saturday November 27 2021, @09:14AM (#1199930)

                Around 1.2 billion people in the world don't have access to power lines or phone lines. Starlink operates globally. Even within the USA many ISPs refuse to run fibre while simultaneously letting their copper infrastructure rot.

                • (Score: 3, Interesting) by canopic jug on Saturday November 27 2021, @02:25PM

                  by canopic jug (3949) Subscriber Badge on Saturday November 27 2021, @02:25PM (#1199983) Journal

                  Starlink operates globally.

                  Not at the current time. It operates mainly in the US with a little in Europe and less in Asia and no presence anywhere in Africa. It does have designs on Nigeria but that country is big and wealthy enough that they can develop their own infrastructure. Supposedly there are also negotiations with South Africa. Even though the satellites are in a relatively low orbit, they are still add an enormous amount of distance to the round trip of any packets they might transfer, compared to ground based fiber. They add at least about 20 to 40 ms [theafricareport.com] to each half of the trip.

                  Costs for deploying fibre are not as high as one thinks, the main obstacle is the obstinacy of the local ISPs with their regional monopolies. Break the monopoly on the 'last mile' and you've solved the problem in the US. As for the nations in Africa, well there are lots of obstacles to doing anything, satellites or not.

                  --
                  Money is not free speech. Elections should not be auctions.
                • (Score: 2) by https on Saturday November 27 2021, @04:13PM

                  by https (5248) on Saturday November 27 2021, @04:13PM (#1199997) Journal

                  I know everyone's got a whoosh in them, but I gotta say yours was pretty low.

                  --
                  Offended and laughing about it.
                • (Score: 1, Flamebait) by quietus on Saturday November 27 2021, @05:46PM

                  by quietus (6328) on Saturday November 27 2021, @05:46PM (#1200010) Journal

                  Those without access to power lines will not have much use of the Internet -- they'll only get confused by all those Nigerian princes offering free money. So, cancelling those out: you do know that you can have the Intertubes over your power line [explainthatstuff.com], don't you?

            • (Score: 5, Interesting) by Runaway1956 on Saturday November 27 2021, @01:51PM (6 children)

              by Runaway1956 (2926) Subscriber Badge on Saturday November 27 2021, @01:51PM (#1199972) Journal

              That prohibitive cost has been overhyped by the telcos. I did the math a couple years ago. There is existing fiber south of the Red River. Laying fiber alongside the highway right past my house, and continuing north another 25 miles would make fiber accessible to 8 different small communities. If uptake were 30% in those communities, the cost would be recovered in ~ 2 years.

              In point of fact, after I did all the math, our electric coop got a grant from the government, and they are doing it. The telcos won't touch it, but the electric company sees profit in it. Even if I am completely wrong, and there is no profit for 5 years, it's well worth it. All the people like myself who suffer with slow internet that frequently goes down can suddenly join the world in the electronic age.

              There is surely some population density where pushing fiber becomes uneconomical. That density is far lower than the telcos have been saying. Don't expect fiber in much of West Texas anytime soon, but all of Arkansas, all of Oklahoma, and the eastern 1/3 of Texas can be served economically. No question of it.

              • (Score: 5, Interesting) by Immerman on Saturday November 27 2021, @02:50PM (3 children)

                by Immerman (3985) on Saturday November 27 2021, @02:50PM (#1199986)

                Unfortunately even best-case idealized capitalism is designed to maximize return on investment, not fill every financially viable niche.

                I.e. delivering internet to those communities might pay for itself in two years, but that just means telco companies have no reason to touch it until they've exhausted *every* investment opportunity that will pay for itself in 23 months or less. And they just don't have enough resources to even make an appreciable dent in that list.

                Co-ops in contrast are specifically in the business of providing valuable services to their communities. While making financial sense is still necessary for a viable opportunity, they generally don't care so much how the return on investment compares to other opportunities. Especially since there's usually a substantial overlap between their customers and investors, so that any profits are literally coming out of their investors' pockets.

                • (Score: 2) by PiMuNu on Sunday November 28 2021, @10:27AM (2 children)

                  by PiMuNu (3823) on Sunday November 28 2021, @10:27AM (#1200188)

                  > best-case idealized capitalism is designed to maximize return on investment, not fill every financially viable niche.

                  This is probably a good thing - prioritise the big population centres first where return on investment is highest. It is capitalism doing what it is supposed to (for once).

                  • (Score: 2) by Immerman on Sunday November 28 2021, @03:13PM (1 child)

                    by Immerman (3985) on Sunday November 28 2021, @03:13PM (#1200227)

                    Define "good".

                    It's certainly more profitable, but means they will spend enormous amounts of money on lobbying to maintain their near-monopoly status and obscene profit margins in those cities, or advertising and deploying trivial upgrades (like "fake" 5G that's no faster than 4G) to attract those profitable customers away from their rivals long before they even consider trying to provide service to less profitable rural areas.

                    • (Score: 0) by Anonymous Coward on Monday November 29 2021, @04:41PM

                      by Anonymous Coward on Monday November 29 2021, @04:41PM (#1200576)

                      Yeah, about 10 years ago weren't they given many millions of dollars to expand to rural areas and they more or less spent it on themselves?

              • (Score: 3, Informative) by VLM on Saturday November 27 2021, @08:32PM (1 child)

                by VLM (445) on Saturday November 27 2021, @08:32PM (#1200047)

                the electric company sees profit in it.

                As a (former?) insider, the way it works is the electric company NEEDS a substantial mesh network for SCADA where-ever it runs power lines, much like railroads.

                And the cost of physical cable is VERY low compared to labor. So install a 144 fiber cable instead of a smaller cable and sell most of the fibers to "someone" probably someone willing to stick 10G ethernet optics on each end and sell ISP connections. I mean, they NEED several pairs depending on shape of network, so every pair they sell is pure profit to the electric company (or railroad).

                In the VERY long run, and it might take a long while, if you're on the electric power grid you're going to have internet access.

                Would the electric company ever trust Starlink enough to run its entire SCADA system over it? Probs not. So in the long enough run, its going to be a financial competition between "selling extra fiber capacity for pure profit" vs literally launching orbital rockets and therefore I think in the very long run, the space satellites are doomed.

                To some extent the idea of satellite internet is a long game play on the grid going down and everyone going local solar or similar. That seems pretty likely in, like, Africa, and pretty unlikely in places like NYC.

                • (Score: 2) by Immerman on Sunday November 28 2021, @03:52PM

                  by Immerman (3985) on Sunday November 28 2021, @03:52PM (#1200237)

                  Do they use fiber for SCADA though? I would have thought the necessary bandwidth was plenty low enough to superimpose a signal on the power lines themselves. The bandwidth limits meant the technology never really caught on for commercial use, but nobody's streaming video to a remote sensor - a few MB/s is probably enough to serve every power-grid sensor in NYC.

                  Meanwhile Starlink is explicitly NOT targeted at places like NYC - satellites just can't handle the kind of signal density needed to serve a major metropolitan area - they only have a few satellites in range of any given location at a time, trying to serve NYC would mean millions of clients per satellite. Not going to happen except perhaps for a relative handful of customers that want a mobile option, or (eventually, supposedly) a lower-than-fiber latency intercontinental link for high-frequency trading. Parasitic, but profitable, and it's physically impossible for (existing) fiber to compete with the speed of laser through vacuum.

                  Instead it's explicitly targeted at rural areas where local infrastructure is not profitable enough to be worth deploying. And even in the US there's plenty of places that lack even cell phone coverage, much less vastly more expensive per-house services. Even power is a dubious proposition - in many places you can easily be looking at 10's of $1,000s to get power delivered from the main line to your housing site, which makes off-grid solar look far more attractive. And of course there's the 71% of the Earth's surface that will never get ground based service on account of being ocean.

                  Plus, it's not like the cost of deploying satellites is fixed wither, in fact it's already posed to fall dramatically wthin the next decade. Starlink satellites are relatively small, at 100-500kg apiece, but at current launch prices that's still somewhere around $200,000 to $1,000,000 each to orbit (based on Falcon 9 commercial prices), while Starship should eventually drop those numbers to around $2,000 to $10,000, and future launch options will drop the price even further.

      • (Score: 3, Informative) by turgid on Saturday November 27 2021, @10:41AM

        by turgid (4318) Subscriber Badge on Saturday November 27 2021, @10:41AM (#1199932) Journal

        Space telescopes have a better view than ground-based telescopes anyway, since the atmosphere filters a lot of the interesting electromagnetic radiation. But I agree that the night sky will be much the worse for these constellation of thousands of small satellites. I recently moved back to the remote countryside after over two decades in towns near big cities. I had forgotten how awesome the dark sky is. It's truly breath-taking on a clear night.

    • (Score: 5, Interesting) by bradley13 on Saturday November 27 2021, @11:35AM (4 children)

      by bradley13 (3053) on Saturday November 27 2021, @11:35AM (#1199943) Homepage Journal

      I really hope you're right. The current James Webb telescope is nuts, because they view it as a generational project. It has to be perfect, failure is not acceptable. It would be far better to put up a telescope every year or two - then they don't have to be perfect, some can fail, and it would be no big deal.

      Telescopes at the Lagrange points. Telescopes on the back side of the moon. Telescopes all around Earth's orbit, so we can get some decent parallax. And none of them subject to problems from near earth satellites. UV telescopes, Xray telescopes, visible light telescopes, radio telescopes. If space access becomes cheap and reliable, it's all possible.

      --
      Everyone is somebody else's weirdo.
      • (Score: 2) by Runaway1956 on Saturday November 27 2021, @02:00PM (3 children)

        by Runaway1956 (2926) Subscriber Badge on Saturday November 27 2021, @02:00PM (#1199976) Journal

        You're on the right track, but surely you can think even bigger. Something like the Webb telescope parked in three (or more) places in earth's orbit, 90 degrees and 180 degrees. Send one to Mars, and each of the remaining planets. They need not all be the exact same type of observatory, either. Putting one over Mars would be cool, but you want to look down too.

        But, I agree. If you launch 6 observatories this year, and 3 of them die within the first 5 years, big deal. Replace them, launch some more, and life goes on. No need to guarantee that every observatory survives 10 years, or 20, or 100. 20 years from now, technology will probably be capable of launching thousands per year. Right after Japan and Korea set up mining and manufacturing operations in the asteroids.

        • (Score: 2) by Immerman on Saturday November 27 2021, @03:59PM (2 children)

          by Immerman (3985) on Saturday November 27 2021, @03:59PM (#1199995)

          What would be the point of telescopes in all those different places?

          It only makes sense for studying things within the solar system, everything else is so far away that once you're out of Earth's broadcasting sphere (such as behind the moon) the view is basically the same from anywhere in the solar system. Unless you're creating an insanely large telescope array specifically to exploit the miniscule differences - in which case you're far more interested in the distance between telescopes than what they're near, so putting them in a ring around the sun as far out in the outer system as we can manage would probably make the most sense. Possibly in a plane tilted far away from the ecliptic, so that the array could also be better focussed on things within the system as well.

          Now, once we have a presence on Mars it could make sense to put an expensive telescope in orbit where it can still be serviced while being well positioned for mapping the asteroid belt in detail from a closer vantage point. Without such a service-friendly presence though, it almost certainly makes sense to just put it in a solar orbit much closer to the belt.

          For pretty much every other location in the solar system, the only reason to put a telescope there is if you're specifically looking at something nearby - which mostly means looking down at planet(oid)s.

          Earth's Lagrange points [wikipedia.org] are special only because they're energetically nearby locations that are physically distant but maintain a stable orbital relationship with us, which is useful both for coordinating observations and being able to better ignore spectrum contamination from Earth. The L4 and L5 points for example lead and trail Earth by 60 degrees, making a 1AU equilateral triangle with Earth and the sun, (90* from Earth is orbitally unstable, and will likely end up "orbitting" the nearby L-point, wandering from 90* to probably around 40*(?) and back again). There's also the L3 point 180* away on the opposite side of the sun, so it's possible to get a roughly equilateral triangle of telescopes around the sun with Earth as a "fourth wheel" on one leg.

          • (Score: 2) by Runaway1956 on Saturday November 27 2021, @07:30PM (1 child)

            by Runaway1956 (2926) Subscriber Badge on Saturday November 27 2021, @07:30PM (#1200033) Journal

            The point would be, bandwidth, parallax, redundancy, AND you can see things from six, or twelve, or 24 different places that you can't see from one or two places. I didn't mention telescopes above and below the ecliptic, did I? Yeah, we need them. 1, 2, or more AU above the ecliptic, and another below, would give us an awesome overview of everything in the system. Of course, I'll admit that my perspective isn't only science. Add in a military background, and you can probably see the benefits of being able to track random rocks in space. That Doomsday Planet Killing Rock from out of nowhere would be much easier to spot, and to track, if nothing occludes the rock from view.

            And, again, I think I mentioned that the astronomy platforms can easily do double or triple duty, for whatever purposes we can imagine. How 'bout a weather sat for Mars, or for Mercury or Venus?

            • (Score: 2) by PiMuNu on Sunday November 28 2021, @10:31AM

              by PiMuNu (3823) on Sunday November 28 2021, @10:31AM (#1200190)

              > bandwidth

              Yes

              > parallax

              Only with nearby stars - so not relevant for JamesWebb.

              > redundancy

              Yes

              > AND you can see things from six, or twelve, or 24 different places that you can't see from one or two places.

              Why? Earth, sun or moon will move out of the way pretty quickly.

  • (Score: 3, Interesting) by MIRV888 on Saturday November 27 2021, @10:38AM (10 children)

    by MIRV888 (11376) on Saturday November 27 2021, @10:38AM (#1199931)

    I am not an astronomer. My question is this. Once these various constellations of satellites are deployed could a collision of 2 satellites in orbit lead to a cascading series of collisions?

    • (Score: 3, Informative) by turgid on Saturday November 27 2021, @10:42AM (1 child)

      by turgid (4318) Subscriber Badge on Saturday November 27 2021, @10:42AM (#1199933) Journal
      • (Score: 0) by Anonymous Coward on Saturday November 27 2021, @01:56PM

        by Anonymous Coward on Saturday November 27 2021, @01:56PM (#1199975)

        SpaceX can pivit to MIC income in the next global war, by redirecting starlink to starwar programming.

    • (Score: 2, Informative) by pTamok on Saturday November 27 2021, @11:50AM

      by pTamok (3042) on Saturday November 27 2021, @11:50AM (#1199945)

      It looks like that is the case.

      https://en.wikipedia.org/wiki/Kessler_syndrome [wikipedia.org]

      The Kessler syndrome (also called the Kessler effect, collisional cascading, or ablation cascade), proposed by NASA scientist Donald J. Kessler in 1978, is a scenario in which the density of objects in low Earth orbit (LEO) due to space pollution is high enough that collisions between objects could cause a cascade in which each collision generates space debris that increases the likelihood of further collisions.

    • (Score: 3, Insightful) by Runaway1956 on Saturday November 27 2021, @02:03PM

      by Runaway1956 (2926) Subscriber Badge on Saturday November 27 2021, @02:03PM (#1199978) Journal

      That has been discussed often. The simple answer is yes. But, even if a major catastrophe wiped out all of the low earth orbit satellites, almost all of it will fall into the atmosphere within a short time. Debris is highly unlikely to gain enough energy to be flung into a higher orbit.

    • (Score: 0) by Anonymous Coward on Saturday November 27 2021, @02:59PM (5 children)

      by Anonymous Coward on Saturday November 27 2021, @02:59PM (#1199988)

      Envelope calcs that might help this discussion?

      Surface area of the Earth in Km^2 = 4 pi r^2 ~ 4 * 3.14 * 6371 * 6371 = 510,000,000 Km^2

      510,000,000 Km^2 / 42000 Starlinks ~ 12000 km^2 per Starlink (on average).
      Sq.Rt 12000 Km^2 ~ 110 Km

      If evenly distributed there would be one Starlink over every square of 110 Km x 110 Km. But they are probably biased away from polar orbits (less customers there). Initial guess = double this density in temperate/tropical regions?

      Is this dense or sparse? Discuss!

      • (Score: 4, Interesting) by maxwell demon on Saturday November 27 2021, @04:00PM (3 children)

        by maxwell demon (1608) on Saturday November 27 2021, @04:00PM (#1199996) Journal

        Satellites are not just sitting there, they're orbiting. Two satellites that are currently on the opposite side of the planet, but whose trajectories intersect will collide. Therefore the space per satellite is the wrong measure. Note that two orbits at the same height necessarily intersect (twice, in fact); that intersection however is no problem if the satellites pass it at different times. I'm however too lazy now to work that out.

        --
        The Tao of math: The numbers you can count are not the real numbers.
        • (Score: 2) by Immerman on Saturday November 27 2021, @05:10PM (2 children)

          by Immerman (3985) on Saturday November 27 2021, @05:10PM (#1200004)

          >Note that two orbits at the same height necessarily intersect (twice, in fact)
          Only if they're perfectly circular - it's quite possible for two slightly elliptical orbits to play "leapfrog", alternately passing above and below each other at the not-quite-intersection points of closest approach. But most constellations stick to circular orbits.

          >that intersection however is no problem if the satellites pass it at different times.
          Only if their orbits are *perfectly* synchronized - otherwise they'll be in different relative positions with every pass through the intersection until, eventually, they collide.

          • (Score: 2) by VLM on Saturday November 27 2021, @08:40PM (1 child)

            by VLM (445) on Saturday November 27 2021, @08:40PM (#1200048)

            it's quite possible for two slightly elliptical orbits

            Agreed in practice.

            In theory there is no closed form for three body gravity orbits and there will be some chaos. In practice, examples like the sun-moon-earth system haven't collided after a long time and will not for a long time in the future.

            • (Score: 0) by Anonymous Coward on Sunday November 28 2021, @01:03PM

              by Anonymous Coward on Sunday November 28 2021, @01:03PM (#1200208)

              Such an engineer comment, trying to appear smart through technicalities. How many fetuses you eating before church?

      • (Score: 2) by Immerman on Saturday November 27 2021, @05:02PM

        by Immerman (3985) on Saturday November 27 2021, @05:02PM (#1200003)

        I think they actually bunch up near the poles, just due to the way the "grids" made by circular orbits work: Starlink" rel="url2html-31971">https://en.wikipedia.org/wiki/Starlink#/media/File:Starlink_SpaceX_1584_satellites_72_Planes_22each.png">Starlink [soylentnews.org] orbital paths on Earth

        In a discussion of density or sparcity, some mention of speed is probably relevant - low orbit speed is above 7.5km/s, so crossing that 110km area takes less than 15 seconds.

        More relevant though is periodicity. For a collision to occur two things must be true - two orbits must intersect closely enough that a collision is possible, and the two satellites must both be passing through that intersection at the same time.

        A collision in any single pass is extremely unlikely. But if the orbits are stable then that intersection point will remain in place indefinitely, and every time one satellite passes through it, the other will be in a different place in its orbit - eventually a collision *will* occur, the only question is how long it will take.

        Of course in the real world no orbit is perfectly stable and orbital drift may well remove the intersection before a collision can occur, but as the amount of debris increases so does the frequency of orbital intersections, until eventually you're drifting out of one intersection only to enter another, and are continuously under threat from several different potential collisions, and and the expected time until you collide with something begins to drop precipitously. And once you're fully above the atmosphere the debris will remain there indefinitely - if we never perform any cleanup ourselves then spacers a thousand years from now will still be dodging orbital junk we dumped there in the 60's.

        Even before you get to a full-on Kessler syndrome, when you do something like blowing up a satellite in a relatively low-energy explosion you create a cloud of larger debris that's all still traveling on roughly the same orbit as the original satellite, which rapidly becomes a planetary ring of debris whose component orbits fill a much larger orbital volume than the original satellite, with hundreds if not thousands of fragments all in different places in their orbit, greatly increasing the chance of collision for anything intersecting that ring.

        Combined you get the real the real long-term threat with anything not subjected to atmospheric drag - given enough time *everything* will collide, and every time there's a collision you convert a piece of large junk into a ring of smaller junk, increasing the risk of further collisions. And even in a very optimistic low-energy collision, where two objects are in virtually identical orbits only 10 degrees out of plane, you're still easily looking at more than 1km/s relative speed differences, on par with muzzle velocities in high power rifles, and at 15* out of plane you're into the range of anti-tank guns.

  • (Score: 2) by oumuamua on Saturday November 27 2021, @02:48PM (1 child)

    by oumuamua (8401) on Saturday November 27 2021, @02:48PM (#1199985)

    We thought the space age was starting 50 years ago with the Apollo Missions but the economics could not sustain it. We had to wait 50 years for the technology to catch up and make it economical, now you have good ROI with things like Starlink and space tourism.
    Astronomy had a 50 year run with very little space activity getting in the way. Now, as they say, if you can't beat them join them.

    • (Score: 0) by Anonymous Coward on Saturday November 27 2021, @05:13PM

      by Anonymous Coward on Saturday November 27 2021, @05:13PM (#1200005)

      Indeed. The spoils always go to the rich. Be happy with the crumbs you had when you could, and stop complaining.

  • (Score: 3, Informative) by VLM on Saturday November 27 2021, @08:50PM (2 children)

    by VLM (445) on Saturday November 27 2021, @08:50PM (#1200051)

    Up to a third of all the data taken by the telescope could be seriously affected

    The engineering solution is you build three scopes hundreds of miles apart and you'll get the data.

    On a meta level that's what we're doing, as long as the total world wide capacity of ALL observatories, big and small, increases faster than the impairment due to any cause, then we'll continue to have a net gain of scientific research.

    Remember there's immense bottom up pressure from amateurs "stacking" multiple exposures to find novas, comets, do photographic brightness measurements, etc. I've fooled around with that and if only a third of my stack exposures were F-d up, I'd be pretty happy LOL. And guys booking time at the crappy little very much not big name uni observatory locally, etc.

    Actually doing real science, where you don't know the conclusion before you start the research, does tend to teach patience. So they'll have more patience. OK then?

    I'm just saying the guy is handling this all wrong. Instead of whining about how we need to cancel trillion dollar projects, he should whine that we need two more millions of dollar observatories to keep up. Presumably the corporate income tax alone on starlink could eventually over the years, slowly fund 10000 more observatories, so who cares if each one is individually running at 1/3 theoretical ability?

    Its like your classic little kid whining about pie slices, would you rather have 100% of 1 pie, or 33% slice of each of 10000 pies?

    • (Score: 0) by Anonymous Coward on Saturday November 27 2021, @10:46PM

      by Anonymous Coward on Saturday November 27 2021, @10:46PM (#1200086)

      Fire him. Then he'll be bitching about getting money to eat or how to stay warm in winter, but he won't be bitching about Starlink anymore.

    • (Score: 2) by Runaway1956 on Saturday November 27 2021, @11:00PM

      by Runaway1956 (2926) Subscriber Badge on Saturday November 27 2021, @11:00PM (#1200090) Journal

      Given that none of that is 'wrong', what about amateurs who are unlikely to be able to place three 'scopes hundreds of miles apart?

      Maybe better to mesh network a bunch of amateur telescopes together via internet?

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