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Space NASA Technology

Orbiting 'Rest Stops' Could Repair Crumbling Satellites 59

astroengine writes: Satellites are numerous, vital to many modern activities, and incredibly expensive to build and launch. They're constructed with redundancy and simplicity in mind because if something goes wrong after the satellite reaches orbit, we can't do much to help it. Now, NASA is talking about building an orbital service station that can perform maintenance, repair, and even refueling operations on these satellites. "Is there a way working with humans and robots together to extend the useful life of satellites, by fixing them and by not allowing fuel to spill out, but give it more propellant, close it up and send it on its way?," said Benjamin Reed, deputy director of the Satellite Servicing Program Office at NASA's Goddard Space Flight Center. "Yes, We have the technologies to be able to do it."
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Orbiting 'Rest Stops' Could Repair Crumbling Satellites

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  • This will be fun... (Score:5, Interesting)

    by fuzzyfuzzyfungus ( 1223518 ) on Friday June 19, 2015 @02:05PM (#49947127) Journal
    The technology to safely capture and repair a satellite that may not be in a position to help you(no fuel, engines offline, software issues, etc.) presumably doesn't differ so very much from that required to capture and modify somebody else's satellite, unless it is in the position to evade you with some enthusiasm, or otherwise make a nuisance of itself.

    It would be a tad tricky to snag somebody else's satellite without ground control noticing that something is amiss; but the first time a satellite gets snagged 'on humanitarian grounds', purely to safeguard its orbit from possible debris of course, I predict some exiting diplomatic fun.
    • Comment removed based on user account deletion
      • Plus, unlike an anti-satellite weapon, this is a purely peaceful infrastructure maintenance system; which should make it squeaky clean in terms of relevant treaties on militarization of space!
        • Comment removed based on user account deletion
          • I am amazed no one has made this point about the drone shuttle the Air Force is using recently.

            • I am amazed no one has made this point about the drone shuttle the Air Force is using recently.

              They only want you to think it's a drone; don't tell anyone but in reality it's crewed with miniature astronauts produced at Brookhaven National Lab (I haven't figured out yet if they were shrunken through quantum/relativistic methods or merely genetically-engineered...).

            • Exactly. The US has a perfect anti-satellite weapon and none of the other major powers have said anything about it.

          • Why break it when you can install a 'multi-stakeholder-management module' to enable complimentary offsite telemetry monitoring and(only if necessary, of course) failover control from a US satellite management solutions provider?

            That's the sort of gold-plated support your vendor would charge you through the nose for, provided free as a gesture of goodwill by your friends in McLean, VA!
          • Just wait until the malware companies can afford to launch one of these platforms

            "Is your satellite running slow? Sat-FXR(TM) has detected 4763 viruses and 1723 malware programs slowing down your satellite. Sat-FXR(TM) can automatically fix these issues for the low price of $85,000,000. Would you like to pay by credit card? If not, your satellite may deorbit in the next 36 hours."

      • Two simple points

        This was a standard feature of the Space Shuttles. One of the prime selling points was satellite retrieval. Personally I wish they kept one shuttle operational to retreive the hubbell when it is time for it to be retired.

        The X-37 has a cargo bay, and is operated in secret by the US military. It can already do that however it's orbit is easy to track.

        So you are ignoring 40 years of things other people already knew.

    • The satellite maintenance we have studied and performed (Hubble, and the Space Station) always assumed the satellite was designed for it. That means a "grapple fixture" (a hard point designed for grabbing), and provisions to change out equipment or refuel. Most satellites today are not designed for maintenance, because there is no way to do it. Hubble and the Station have access to robot arms, EVA humans with tools, etc. Satellites in GEO don't.

      Once a service station is available (and an orbital tug to

    • The fuel cost of moving a satellite to the depot is non-trivial. (Orbital Maneuvers [wikipedia.org]) , so I think it will take a lot of diplomatic fun before it would even be done.
    • by Livius ( 318358 )

      I think they'll be able to figure those issues out. Piracy has existed for thousands of years.

  • by fiordhraoi ( 1097731 ) on Friday June 19, 2015 @02:09PM (#49947167)
    Would this allow for more complex satellite design, knowing that in-orbit maintenance is available? Could NASA charge commercial industries and other governments for maintenance service of their satellites? If so, would this be a feasible source of moderate funding? Will companies wanting to send up satellites now have to sit through the "extended warranty" sales pitch too?
    • NASA probably would not be in the business of fixing satellites for other people, just their own. Once the technology is available, other people will likely take it up as a profit-making business. Not having to write off $300 million satellites when they break is worth billions a year. The most qualified "satellite repair dudes" will be the original satellite makers, since they know the most about them in the first place.

      • by umghhh ( 965931 )
        I think you are wrong about it who is going to do this. We know that H1Bs can do it cheaply and maybe there can be savings on return trip?
    • Would this allow for more complex satellite design, knowing that in-orbit maintenance is available?

      It is likely it will lead to simpler, cheaper, designs. Currently, a single failure can cause the loss of an extremely expensive satellite, so they are built with a lot of redundancy and hardened components. If parts can be replaced, then a single failure is less catastrophic, so a simpler modular design, allowing easy swap-outs, becomes more practical.

  • by Anonymous Coward

    Repairing them sounds nice, but spares are a significant problem, orbital spots in GEO are precious, and each generation of satellites is substantially more capable. For physics-limited satellites, which is to say imagery satellites, refueling makes sense. However, every other category of satellite I'm aware of has significant improvements with each generation of launch.

    Much more plausible for that small set of satellites is a mid-life docking, where the mid-life craft is much smaller, and has just consumab

  • Tug boats (Score:5, Insightful)

    by Immerman ( 2627577 ) on Friday June 19, 2015 @02:14PM (#49947235)

    Of course, the "rest stops" with their stockpiles of fuel and parts will probably be massive structures, so we'll also need "tug boats" to transfer the satellites from their original orbit to one that can dock with the rest stop, and then return it to it's designated orbit again after repair and refueling. Still far less energy-intensive than sending up a replacement satellite though. And if only refueling is needed then it's probably easier still to outfit the tug with a refueling waldo that can mate with a standardized fuel receptacle on the satellite - then the tug only has to make a single trip from the rest stop/fuel depo to whatever wonky orbit the satellite is in, and the satellite itself need never move at all.

  • This isn't a bad idea. Especially that the normal satellite lifespan is only about 15 yrs.
  • by lhowaf ( 3348065 ) on Friday June 19, 2015 @02:26PM (#49947321)
    This makes me wonder if spy (or other sensitive) satellites have tamper-detection built in.
    • Yep, every spy satellite has a little switch inside it. If anybody gets inside, that switch clears a register on the motherboard, and it'll show a "WARNING: Case Opened" the next time it POSTs, accompanied by a glaring 1-second beep.
      • by lhowaf ( 3348065 )
        Maybe they should have a label. "Spy Satellite: KEEP OUT!"
        • Don't ask me how I know this, but a major scandal with the NRO (National Reconnaissance Office) is about to erupt: apparently they've been forgetting to push the "turbo" button before handing the keyhole sats off to NASA for launch. As a result, America's espionage capability is hamstrung by an artificially constrained clock speed. :O
  • by frovingslosh ( 582462 ) on Friday June 19, 2015 @02:30PM (#49947367)

    This makes plenty of sense if the next generation of satellite were to standardize some things to plan for this, but is extremely unlikely to work for current satellites that were not designed with service in mind. The current satellites don't even have simple things like standardized and accessible fuel fittings (since it was never expected that this would happen and they were considered disposable) or even physical hold points where a service device could latch on. A good modular design for module replacement that allows for access and plug-ability would obviously help too, even if specific modules had to be lifted into space before a service mission.

    Before N.A.S.A. wastes too much of its ever dwindling budget (insert here comment about how we have so much money that we can give the poor free Internet and Obamaphones), they should create a set of standards and see if they can get the industry to willingly adopt them with the expectation that it would facilitate service in the future. Once a fair number of devices that were deigned planning on being able to be serviced if a service station were ever deployed are in orbit, then putting that station in space could make sense.

    • by Anonymous Coward

      This isn't exactly new..

      https://en.wikipedia.org/?title=STS-49 [wikipedia.org]

      STS-49 was the maiden flight of the Space Shuttle Endeavour. The primary goal of its nine-day mission was to retrieve an Intelsat VI satellite (Intelsat 603, which failed to leave low earth orbit two years before), attach it to a new upper stage, and relaunch it to its intended geosynchronous orbit. After several attempts, the capture was completed with a three-person extra-vehicular activity (EVA). This was the first time that three people from the same spacecraft walked in space at the same time, and as of 2014 it was the only such EVA.[1] It would also stand until STS-102 in 2001 as the longest EVA ever undertaken.

    • While standards would be great going forward, it does not follow that existing satellites can't be repaired. Satellites have to be fueled before launch and their makers do not design unique fuel fill ports for each satellite they build. There are undoubtedly a few common sizes and it should not be that difficult to equip a repair station with a set of adaptors or a universal fill device that can work with a large fraction of existing fill ports. Same goes for grappling points. All satellites have fittings t
    • Before N.A.S.A. wastes too much of its ever dwindling budget (insert here comment about how we have so much money that we can give the poor free Internet and Obamaphones), they should create a set of standards and see if they can get the industry to willingly adopt them with the expectation that it would facilitate service in the future.

      I would guess that NASA is going to arrive a day late and a dollar short to this particular party. SpaceX intends to put up a constellation of a whopping 4000 satellites. OneWeb plans to put up a constellation of 700 satellites. The SpaceX satellites are classified as small-sats, and due to volume production, should be considerably cheaper than the equivalent tonnage in larger satellites, but a small-sat is still up to 500kg. It may be worthwhile to perform on-orbit servicing of something the weight and

  • by Anonymous Coward

    Hmm, this was what the US shuttles were supposed to have been able to do. In practice, they could only reach low earth orbit, but they did service the Hubble at least.

    • by k6mfw ( 1182893 )

      Yes, Solar Max was the first to be repaired. And there were some other satellites that were retrieved and brought back.

      But (yes there are always bad excuses) cost of flying Shuttle is far more expensive than the satellite itself. I remember in 1970s/1980s there was lots of talk about space tugs, then poof all such articles disappeared. Later in 1990s in a project management class, instructor mentioned a parametric study on space tugs resulted in energy changes to change orbits from typical 250mile at 28.5

  • by phantomfive ( 622387 ) on Friday June 19, 2015 @02:38PM (#49947441) Journal
    But would repairing a satellite be cheaper than just launching a new one?
  • Orbital mechanics (Score:5, Insightful)

    by Dan East ( 318230 ) on Friday June 19, 2015 @02:42PM (#49947481) Journal

    The huge problem is orbital mechanics. The delta-V difference between satellites is enormous. Polar orbit, geosynchronous orbit, low-earth orbit, etc, etc. The difference in velocity between them is more than any satellite or service vehicle could realistically overcome (assuming you want to visit more than one satellite every couple decades). Satellites in geostationary orbit might be doable, because they all have to orbit relative to the earth's rotation, so traversing from one to another might be reasonable. However they are so far up there that it would still require covering a lot of distance to get from one to another.

    • by 0123456 ( 636235 )

      A tug in orbit can use a much more efficient engine than a satellite launched directly from Earth. The big problem is likely to be damage from passing through the Van Allen Belts if you use ion drive or some other slow but fuel-efficient mechanism.

    • Covering a lot of distance is no problem if you have weeks to do it in. Traveling through space is free as long as you aren't expending Delta V during the course of it.
  • by Mike Van Pelt ( 32582 ) on Friday June 19, 2015 @02:43PM (#49947497)

    This would probably be useful only for groups of satellites in the same orbital plane. The application that comes to mind is all the satellites in increasingly crowded geostationary ("Clarke") orbit, with the orbital plane going through the equator. Orbital plane changes are one of the most expensive maneuver there are in orbit. (This was one of the criticisms of the movie "Gravity". The only way a space shuttle can get from the Hubble's orbit to the ISS orbit is to land and get re-launched into the proper orbital plane. Doing it in a backpack? Ludicrous.)

    A satellite repair bot making its rounds through Clarke Orbit could be extremely useful.

  • by account_deleted ( 4530225 ) on Friday June 19, 2015 @02:48PM (#49947541)
    Comment removed based on user account deletion
  • Is there a reason we do not use a slow speed to orbit?

    Say, a large zeppelin floats as high as possible, fires a jet engine to go higher, then a rocket to leave the atmosphere.
    Or couldn't a zeppelin carry a Xenon Thruster engine?

    Does it have to be short duration, high thrust; never long duration, low thrust to get to orbit?
    • This should answer your question https://what-if.xkcd.com/58/ [xkcd.com]

      Basically, the energy intensive part of getting to orbit isn't getting high, it's going fast enough horizontally. You basically have to be going so fast that the ground falls out from under you (due to the curvature of the Earth) before you can hit it.

  • What about the radiation problem. How are the humans going to be protected from the radiation theses satellites have absorbed in there time in orbit?
  • So... repair and refuel Hubble?

    Or if they can't do that, let SpaceX go up on their own dime and claim salvage?

    Or let Google contract a SpaceX flight or two, go up, and claim salvage?

  • For NASA to build an orbiting depot to refuel/patch its own satellites, and even secret military devices of NATO countries --- the cost/benefit analysis of what is likely to happen can be completely considered --- and no one's job is at stake. Within a government or military entity everything is considered to be a 'mission' that is either a success or a failure.

    But the moment this NASA facility drifts into range of someone else's corporate private property... the clouds will part and the night sky will fil

  • I suspect this idea will never reach fruition because

    • 1. Pound for pound it costs as much to launch fuel to the refueling station as it does to launch new satellites
    • 2. Extra fuel will be required for rendezvous
    • 3. Satellites become technically obsolete pretty quickly, so if your I-SEE-YOU sat's been up there for six or seven years you'd most likely want to replace it with I-SEE-YOU 2 instead of just refueling it.

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