The US Air Force Space Command's 14-month effort to save a $2bn military communications satellite overcame failed thrusters, threatened explosion, space debris, and destructive radiation, thanks in great measure to tiny thrusters with a mere 0.05 pounds of oomph. It wasn't easy, as airforce-magazine.com reports in a blow-by-blow …
Thank you, Captain Obvious.
Damn Dirty Scientists.
Well, its not exactly rocket science...
Ohh wait, it pretty much is.
Buy those engineers a beer, or a kool-aid or whatever liquid they fuel those brain cells with.
The IED in space is a bonus.
@AC: Geostationary - Geosynchronous
AFAIK Geostationary is a special case of Geosynchronous and can only happen if the orbit is exactly over the equator. In other cases the satellite returns to the same spot once a day.
the earth ain't a sphere mr AC.
But what caused it ?
This is an amazing and impressive thing to do, but quite frankly I'm missing the last bit of information as to what caused the somewhat assumed fuel clog which resulted in so much problems ?
After all; if the team were able to conclude with some certainty that a fuel block had to be causing these issues surely they have had information from which they could determine that this was the case? So what was causing the fuel block? Flawed design perhaps or other stuff going wrong ?
"...surely they have had information from which they could determine that this was the case?"
Someone's ex-wife admitted to pouring sugar into the fuel tank?
Re but what caused it
Space gremlins, what else.
Yes that would be interesting to know. Perhaps the fuel froze, which was in turn caused by a failed or non-existent heating device?
Left Over Bits of Cleaning Rag...
in the fuel line was the eventual determination. How they determined there were bits of cleaning rag left over, I have no idea...
...mine's the one with the torn cleaning rag in the pocket...
I know the quote says a full mission life cycle but it would be interesting to know if the satellite lifetime has been impacted by this - particularly the hydrazine burns.
Good to hear of ion thrusters being used in a big way. Where do the xenon atoms come from in the first place and how depleted is this source now?
The xenon comes from a fuel tank. It's just that at the rate it's expended, a relatively small supply of xenon can be used for tens of thousands of times longer than a comparable sized conventional rocket can burn as so long as sufficient electricity is available.
Xenon lies above iron in the Periodic Table, so production comes from stars going boom or from the radioactive decay of heavier elements also produced in said explosions. We collect it by fractional distillation of our atmosphere.
Costs on par with beer, by volume (as a gas). And is an intoxicant!
Wait a minute
Space Vehicle 1?
Methinks that would be Sputnik launched in 1957 not some Johnny-come-lately launched in 2010.
You guys are true space nuts
None of the other half dozen sites had links to anything useful. You're the only ones with that AF mag link. Kudos for real journalism & research, guys.
Few days to live
Burnt up all the onboard fuel now eh? Well, the craft's life expectancy is now 24 months at best!
Go on....keep screaming U-S-A , U-S-A while the defence contractors keep shafting Washington!
"Madden said, as a result of the careful efforts to husband SV-1’s hydrazine and xenon fuel during the orbit-raising phases, there will be no reduction in its planned 14-year life."
As I understand it, they were able to use the Hydrazine intended for the main engine, to power the smaller thrusters.
What a relief now the developed world is a little bit safer.
So the conclusion is that they don't actually need the main engine? I thought they engineered these things for minimum weight. Why lug around a main engine that is apparently surplus to requirements?
(btw, that's intended as an ironic remark before someone starts to take it seriously)
Think of this as a 'Flintstones' moment - metaphorically, they stuck their feet through the floorpan and paddled their little space-feet to get to mission orbit.
Now, about that heavy lift capability; Anyone got a space-bronto handy?
Well, I guess this validates the utility...
... of low-thrust, high-specific-impulse ion thrusters.
If whimpy xenon thrusters can help move a satellite from low-/mid-earth orbit to geosync, running continuously for as long as they did, then there should be no problem with using ion engines like VASIMR to cross the Earth-Mars expanse.
Presuming, of course, we can crack the electric power nut. VASIMR takes quite a bit of power, which means any manned spacecraft we send to Mars with a VASIMR engine would almost certainly need a nuclear-fuel based power plant, such as a battery of radioisotope thermoelectric generators (which is likely to be unpalatable to various envirofactions).
Solar panels could -- in theory -- be used to provide the needed electricity, but are vulnerable to damage from interplanetary particulate matter and servo-mechanical failure.*
* "Servo-mechanical failure" refers to the failure of the mechanical equipment used to deploy/retract the solar panels and maintain their orientation.
It's all a balancing act
You can use a bigger/expensive launch vehicle to put it higher, or put a bigger booster on the spacecraft, or you can spend a lot of time doing orbital mechanics games to get it to it's destination.
Depends on how much money/time you have - for some missions spending 5years letting it drift slowly to it's final point might be worth it. For others it would be obsolete when it got there, or would have been clobbered but junk, or some other part would have decayed/warmed up/worn out
All that effort for what? So the Land of the Free can kill people more efficiently? Or, considering it's a comms satellite, make sure they're attacking the right wedding?
Downvote all you want. Like I care.
Or maybe talk to other world leaders so they *don't* go nuking the wrong party tent...?
Naaaah. Clearly, you've got the only purpose for which this might be used ALL figured out. Allow me to congratulate you on your perspicacity and unbiased observational acuity!
The question is still valid and is an obvious gap in the story.
What is this 7-tonne monster going to be used for? X-ray-blast other satellites? Guide missiles into unpatriotic/terrible/evil-axis/copyright-infringing homes? Spy me when I pick my nose?
Somehow I don't feel a bit safer.
It's a Communications Relay Satellite
So various US government entities (primarily the DoD) will have higher bandwidth than the current MILSTAR satellites can provide.
On the behalf of the aliens from "Independence Day"
I thank our Air Force satellite saviors. Now that the communications satellite is in place, the aliens can use it to coordinate their city-destroying rampage.
Next on the alien's pre-invasion checklist--a working firewall and antivirus software!!!!
Geostationay - a bit slow.
Geostationary orbit is fine for high-latency emergency communications between meatware systems. It's also OK for transferring gigabytes of data using large buffers.
But it takes light about a quarter of a second to get up to geostationary orbit and back again (i.e. a network packet round-trip time of half a second). Skynet will need low-altitude satellites, or more probably will just hijack our fibre-optic cables here on the ground.
As for aliens, they must have FTL technology or they wouldn't be here!