henry@zoo.toronto.edu (Henry Spencer) (08/11/90)
In article <13567@ulysses.att.com> smb@ulysses.att.com (Steven Bellovin) writes: >I'm a bit confused. I've seen no mention of refueling the stranded >satellite's maneuvering engines. I know they used a lot of fuel to >stabilize the orbit, and given that fuel supply is often the limiting >factor on the lifetime of such satellites I'd think they'd want to >do something about that. Does anyone have any more information? There has been no mention of refueling, and I suspect they aren't going to do it -- the satellite is not designed to be refuelled in space, and NASA has never tried that sort of thing. (The Soviets do it all the time, but they learned how during space-station operations, something NASA has yet to attempt.) My guess would be that the fuel remaining is sufficient for a good useful lifetime, albeit perhaps a somewhat shorter one than intended. -- It is not possible to both understand | Henry Spencer at U of Toronto Zoology and appreciate Intel CPUs. -D.Wolfskill| henry@zoo.toronto.edu utzoo!henry
palmer@arrester.caltech.edu (David Palmer) (08/11/90)
henry@zoo.toronto.edu (Henry Spencer) writes: >In article <13567@ulysses.att.com> smb@ulysses.att.com (Steven Bellovin) writes: >>I'm a bit confused. I've seen no mention of refueling the stranded >>satellite's maneuvering engines. I know they used a lot of fuel to >>stabilize the orbit, and given that fuel supply is often the limiting >>factor on the lifetime of such satellites I'd think they'd want to >>do something about that. Does anyone have any more information? >There has been no mention of refueling, and I suspect they aren't going >to do it -- the satellite is not designed to be refuelled in space, and >NASA has never tried that sort of thing. (The Soviets do it all the >time, but they learned how during space-station operations, something >NASA has yet to attempt.) My guess would be that the fuel remaining >is sufficient for a good useful lifetime, albeit perhaps a somewhat >shorter one than intended. I heard that, a year or so ago, Hughes patented the idea of, 'Hey, if you let the satellite drift a bit, you won't use up as much fuel. All you have to do is move the ground antenna a bit to track it.' Was there anything more to the patent? Anyway, I guess that they will probably husband the fuel a bit more than they would otherwise, by keeping looser tolerances on the station keeping and putting it at one of the more stable longitudes (since Earth is not exactly spheroidal, some geostationary orbits are more stationary than others.) There are things they can do, but I don't know how much they will extend the life. >It is not possible to both understand | Henry Spencer at U of Toronto Zoology >and appreciate Intel CPUs. -D.Wolfskill| henry@zoo.toronto.edu utzoo!henry I'm glad you're no longer trashing Jules Verne. -- David Palmer palmer@gap.cco.caltech.edu ...rutgers!cit-vax!gap.cco.caltech.edu!palmer I have the power to cloud men's minds -- or at least my own.
mmachlis@athena.mit.edu (Matthew A Machlis) (08/12/90)
What do you mean, "during space-station operations, something NASA hass yet to attempt?" Has everyone forgotten about Skylab? I admit myself that Skylab is probably the one past NASA project that I know the least about, but it seemed to be a pretty good station. When I saw the backup Skylab at the Air & Space Museum last week I was amazed at how large it was. Much larger than the Soviets' current stations. I still can't believe we just let it burn up. -- ---------------------------------------------------------------------------- Matt Machlis MIT Space Systems Laboratory (617)253-2272
henry@zoo.toronto.edu (Henry Spencer) (08/12/90)
In article <1990Aug11.195433.1913@athena.mit.edu> mmachlis@athena.mit.edu (Matthew A Machlis) writes: >What do you mean, "during space-station operations, something NASA hass >yet to attempt?" Has everyone forgotten about Skylab? ... Just about. :-) Skylab never attempted to be an operational station the way Mir and the later Salyuts did, and in particular was not capable of being resupplied in orbit. -- It is not possible to both understand | Henry Spencer at U of Toronto Zoology and appreciate Intel CPUs. -D.Wolfskill| henry@zoo.toronto.edu utzoo!henry
pstinson@pbs.org (08/13/90)
In article <1990Aug12.005525.5284@zoo.toronto.edu>, henry@zoo.toronto.edu (Henry Spencer) writes: > > Skylab never attempted to be an operational station and in > particular was not capable of being resupplied in orbit. I believe the three Apollo spacecraft which docked with Skylab DID carry up supplies with them, such as a new solar shade and equipment used on a spacewalk to fix external damage. They also carried food and other supplies. Is this not a resupply capability? Apollo was afterall was much bigger than the Soyuz or Progress vehicles which resupply Mir.
GIPP@gecrdvm1.crd.ge.com (08/14/90)
In article <9867.26c695f2@pbs.org>, pstinson@pbs.org says: > >In article <1990Aug12.005525.5284@zoo.toronto.edu>, henry@zoo.toronto.edu y >(Henr >Spencer) writes: >> >> Skylab never attempted to be an operational station and in >> particular was not capable of being resupplied in orbit. >I believe the three Apollo spacecraft which docked with Skylab DID carry up >supplies with them, such as a new solar shade and equipment used on a >spacewalk >to fix external damage. They also carried food and other supplies. Is this >not a resupply capability? Apollo was afterall was much bigger than the Soyuz >or Progress vehicles which resupply Mir. If memory serves me correct, wasn't skylab launched with most of the consumables onboard already? Also, I believe the original thread of questioning was the resupply- ability of the manuevering rockets of satelites/skylab. To my knowledge, skylab was not intended to be refueled. Also, didn't they leave off large enough motors to effectively boost it into higher orbits (to save it from reentry)? something to do with a reluctance to ship up fuel on the shuttle (which was to be the "resupply" vehicle eventually). I may be wrong, a good memory doesn't go as far as it used to. pete
henry@zoo.toronto.edu (Henry Spencer) (08/14/90)
In article <9867.26c695f2@pbs.org> pstinson@pbs.org writes: >> Skylab never attempted to be an operational station and in >> particular was not capable of being resupplied in orbit. >I believe the three Apollo spacecraft which docked with Skylab DID carry up >supplies with them... They carried up very small amounts of supplies, alas. Most of what the astronauts ate, drank, and wore was pre-packed aboard Skylab. The Apollo- Saturn IB combination simply didn't have a very large cargo capacity. And certain key consumables, like oxygen and maneuvering fuel (nitrogen), came from supply tanks that could not be refilled in orbit. >... Apollo was afterall was much bigger than the Soyuz >or Progress vehicles which resupply Mir. It was much bigger than Soyuz, but Soyuz's cargo capacity is roughly one toothbrush per passenger. Progress is roughly the same size, but it is a dedicated freighter -- no life support and no reentry capability -- which can carry quite a bit. -- It is not possible to both understand | Henry Spencer at U of Toronto Zoology and appreciate Intel CPUs. -D.Wolfskill| henry@zoo.toronto.edu utzoo!henry
thomas@mvac23.UUCP (Thomas Lapp) (08/16/90)
palmer@arrester.caltech.edu (David Palmer) writes: > I heard that, a year or so ago, Hughes patented the idea of, 'Hey, if > you let the satellite drift a bit, you won't use up as much fuel. All > you have to do is move the ground antenna a bit to track it.' Was there > anything more to the patent? Didn't know it was patented, but I've heard the idea of letting them drift a bit. When they get too far out of line, they are sent commands to 'fly' them back into the proper place. Someone told me once that that is the reason satellites are sometimes called 'birds', since they are 'flown'. - tom -- internet : mvac23!thomas@udel.edu or thomas%mvac23@udel.edu uucp : {ucbvax,mcvax,psuvax1,uunet}!udel!mvac23!thomas Location : Newark, DE, USA Quote : I know how to spell banana, I just don't know when to stop -- The UUCP Mailer
japodaca@hydra.unm.edu (Dr. J. Apodaca CIRT) (10/04/90)
I have a grievance to express. I hope this doesn't come off sounding wrong but over the last few weeks I have seen too much on the subject of parking passes in a subject that should concern, according to the area name, the Space Shuttle. As a suggestion, it would be nice if such infromation were reserved for another area. Thank you and I hope this was received in the spirit it was intended. A Space Enthusiast