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ISS Orbit-Raising Attempt Fails
hpulley writes "ITAR-TASS reports that the Progress cargo ship currently docked at the ISS attempted an orbit raising burn this morning but the engine failed three minutes into the firing. Further burns are cancelled until they figure out the problem and meanwhile, the station continues to lose approximately a kilometer of altitude every week, with the rate increasing as the orbit decays. At present, the schedule says the next Progress, 20P, will be launched on December 21st, nearly 9 weeks from now. Normally the shuttle would also raise the orbit of ISS but it is not scheduled to launch until May 3rd at the earliest. Nominally the ISS orbits at 358km but if it drops to 300km, it may decay in a matter of days. It was down to 340km already on October 13th."
Since I submitted the article, another report has said this morning's emergency is not a problem, and they may attempt another orbit raising burn today. There is lots of time to make a correction and the orbit is OK for now.
$#!^ happens, but why does it always have to happen to me???
The story gives the impression that the ISS is in some sort of dire predicament, however, upon doing the math, one can see that the ISS has roughly 9 months of orbit still in front of it.
Tempest, meet teacup.
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~ |rip/\/\aster /\/\onkey
You'll need more than your tin foil hat if the ISS lands on you.
I used to have a better sig but it broke.
for building an orbiting space station without any real scientific purpose, but I built it anyway. And then its orbit decayed and it burned up upon reentry, so I built another one . . . /message for you sir
This isn't a good situation, but barring future disasters I'm confident that they'll get a ship up there to boost the ISS to a level where it can be saved for many more decades.
If you want to see the graphical representation of the ISS's altitude, there's a nice chart at Heavens-above.com It's a free sign-up, and the bonus is you can find out when ISS flies over your house so you can see it or even take pictures like I do sometimes.
I had noticed just a few days ago that the orbit was at its lowest point, and was getting concerned about what they were going to do about it.
Saskboy's blog is good. 9 out of 10 dentists agree.
Nine months might sound like a long while. But consider the lead times for rockets. Can an unscheduled mission be planned, built, prepped, tested, rubberstamped and shot into orbit inside nine months?
The first burn will be performed at 5:09pm for 705 seconds, the second at 6:33pm for 700 sec, both with 2.94 m/s delta-V each. Main purpose of the reboost is to set up proper orbit phasing for Progress 20 launch. [The burns will be performed by eight DPO-BT thrusters of Progress 19, from the #1 manifold and will be controlled in attitude by Service Module MNFD thrusters from both manifolds. The 19P burns are steered by the SM motion control & navigation system (SUDN) via the US-21 matching unit (installed in 19P on 9/13). The propulsion systems were tested successfully on 9/15.]
They got 170 seconds out of 1405 seconds or about 12% of a burn. MOSCOW, October 19 (Itar-Tass) --A cargo ship docked at the International Space Station (ISS) fired its engine Wednesday to raise the space research platform into a higher orbit but in about three minutes the engine failed and the operation was canceled.
The correction was to boost the space station more than 10 kilometers further from Earth into an orbit that was to reach 356.8 kilometers on the average.
Normally, ISS goes down by 100-150 meters daily. That's about 3-5KM a month.
Also, there are no Shuttles ready that could boost the orbit either, so the Russians are the ONLY method right now. I'm not sure how fast the Russians can send up another Progess if the one currently docked can't get the job done. This IS a serious risk to the station and crew, but it's not panic time.
and landed in kansas...would it make a sound?
i don't care
That sucks, but I think someone is being a bit sensational. They have almost a year to correct this. They have a mission planned in two months, by that time it will still be at least 330km up. They have been that low before. Also, by your own link, it takes at least three weeks for the orbit to decay from 300km, I have seen others that say up to 3 months. Neither of those are "a matter of days".
This isn't rocket science.
That's the shit that feds me up
Fed up with watching others make impact craters on Mars the international consortium building the ISS have decided to up the ante by making a crater on Earth. Since the only thing they have in space is the ISS it was odds on that they would chose this to crash into Earth. Reports say that it should be a spectacular show especially for the people it hits.
I used to have a better sig but it broke.
These Russians have years of experience in the field. Heck, they had MIR for 15 years. That is, 3 times the time it was intendd to last. Sad that we as Americans can only sit and observe at least for now. Even aftr pumping billions into our space program, I will not be suuprised if things just do not work for us.
Will the same thing happen to ISS that happened to Skylab? A series of incidents (generally involving funding) that results in the space station sinking below a level that it could be lifted out.
Of course there are people in ISS, so it's perhaps a bit too early to wonder if funding would be delayed long enough for ISS to fall to Earth.
“Common sense is not so common.” — Voltaire
So why haven't they put that tether experiment on the ISS that the shuttle ran a number of years ago. Basically it was able to turn orbital motion into electricity or electicity to motion. Next trip take them up a tether and a bunch of solar cell and Fagetaboutit.
I couldn't fail to disagree with you any less.
Well, they have the Soyuz capsules, which were first designed in the 1960s and are currently supplying the ISS because our own shuttles keep blowing up. There was also the Mir, which was falling apart toward the end but still lasted far beyond when its original specs said it would die.
The Russians have had a lot of stuff blow up, but so have the Americans. They have also built a lot of really great technology that is in active use right now.
There are aproximately 4 scheduled Progress missions per year. 12 months divided by four = 3 months lead time.
-everphilski-
Finally, all that spam provides the answer:
Problems keeping it up?
Get v1ag.ra, x4na.x etc. mailed direct to your ISS and end your low-orbit problems with the ladies forever.
OK, jokes over.
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__________
Pre|ension is in the eye of the beholder
4 missions per year does not mean 3 months lead time.
Astronauts train for over a year for their flights. Missions are being prepared for concurrently. I do not know what the required lead time is, but it's undoubtedly greater than 3 months.
Seth
$5 / month hosted VPS on linux = awesome!
IANARocketScientist, and for those other readers who aren't can someone please explain:
Why don't they have ISS in a higher orbit that won't decay as fast/often? And again, pardon my ignorance, but my (un)common sense tells me if they are at a high enough orbit, it shouldn't decay as readily - too high and you have the opposite problem of drifting farther away from Earth.
In other words, rather than having to make orbit adjustments so often, isn't it possible to push it to a high enough orbit that won't require a tweak for a longer period of time?
TIA for n00b-enlightenment.
"But you fuck one goat..."
Perhaps the thing will tumble from the sky into the middle of the ocean. That would accomplish what a lot of people would like to see done. (A government conspiracy to end it at work here? hmmmmmm.) There are many arguments on either side of this coin that are valid, but I for one am going with the school of thought that says that our commitment to this station is something that is impeding the progress of our space mission. I would hate to see all of the effort and money that has thus far been expended gone to waste, but I would also like to see future opportunities for exploration made available. If you want to save something, save Hubble for crying out loud.
That's not what your mom said last night.
A chicken ran by me today yelling, "The sky is falling!!!" I thought he was just delirious from the flu.
Much like how the ISS is slowly decaying orbit over the next NINE months - which will end in atmospheric burnout, my life equally will slip into decay as my next nine months play out, and BAM! Fiery burnout!
Damn you defective condom, damn you! *shaking fist at sky* We should have put a condom on the shuttles!
The orbital correction is a perpetual process. Therefore, the ISS would require a perpetual supply of fuel if it had its own rockets. This infinitely massive space station would immediately suck in the Earth, become a black hole, and devour the solar system, followed by the universe.
No, I think that's not gonna work.
See subject. No astronaut training required at all. Progress missions are robotic resupply and ISS-boosting missions.
-everphilski-
It's not like the ISS is of use to anyone, thanks to it being in its current orbit. Like the Shuttle itself, it was a bad idea poorly implemented. You don't design and implement a space station just so a gaggle of nations can proudly say they have a presence in space, and you don't build a shuttle just because a bunch of Air Force pilots insist on flying a space ship home like an airplane. You do both to accomplish a purpose in space. What is our current mission in space? Besides lining the pockets of the Aerospace Industry, that is. Form follows function. If you don't have a concrete goal to accomplish, you'll never reach it. We have no business being in space without such a goal.
My suggestion: decommission the space station and shuttle, close down NASA, and give the money we currently spend on it to private individuals and companies to do something (tourism, manufacturing, mining, whatever) worthwhile with it. That is the only way mankind will reach the "new frontier", the same way we reached the old one: monitize it.
"My country, right or wrong; if right, to be kept right; and if wrong, to be set right." --Senator Carl Schurz (1872)
There is no problems...even with a Progress engine failure there are several backups, one of which is the Service Module engines that can be fired after the Progress is undocked.
Why? Why have rocket motors built into the station, that you have to refuel? Would such a system be magically less prone to failure than the current system? Why not just use the partially-fueled rocket?
"And yes, things could be better if I were doing it"
Uh huh. Here's a nickel, kid.
Why yes, I AM a rocket scientist!
It occurs to me that station-keeping engines would be an excellent application for ion engines. They don't have the power to push the thing into orbit, but certainly they could be built with enough thrust to counter the atmospheric drag at those altitudes. While it would take a bit of effort to bring the engines up on the rockets, it would probably be more than compensated by being able to shuttle up a small load of xenon every now and then instead of all of the fuel necessary to boost it back into its original orbit.
Maybe it's just convenient to have it ride lower every now and again, but I can't imagine that the fuel saved by the lower orbit compensates for having to push it back up there again. I haven't done the math, but it's possible that ion engines would allow it to stay at a lower altitude indefinitely, since there's no danger of decay.
And while we're at it, maybe we could design these things with just a tad bit of aerodynamic considerations. Ok, I'm truly talking out my backside right now, but it's fun to think about how to avoid this kind of thing.
Wake up - the future is arriving faster than you think.
We obviously want the station properly decommissioned. But it needs to come down. What a waste.
This is my post. There are many others like it. If you don't like what you read here, go try one of the others.
Frankly the station is a great candidate for the addition of ion thruster engines to help maintain altitude.
Not only ion thrusters, but perhaps also 3 or 4 small conventional oxygen/hydrogen rocket engines strategically placed in case the station ever needs some higher amounts of thrust or steering manuvering capability for unforseen emergencies. The extra oxygen and hydrogen stored on board for those engines could also be diverted to fuel cells for emergency power needs and the oxygen for life support. (Scotty!!! we've got a breech of the outer hull from a meteor strike and shields have failed! Divert auxilary power from the thrusters to life support now!!!). The continuous low-level ion thrust could counter the additional drag from the extra weight to maintain orbital altitude, and the other engines would be there for "just-in-case", hoping you'd never really need them.
Of course, we'd need a ship big and reliable enough to get those engines, supplies and installation crew up there to install the stuff... but I digress...
Ok, first, what's up with the moderation on this post? Currently it is -2 Overrated. WTF? Who did TigerNut piss off?
A similar proposal was made by Ben Bova years ago, and I'd be surprised if he was the first. I don't know why pclminion thinks it would be such a hard calculation:
The eccentricity of the orbit is 0.0002300, so we can treat it as effectively circular.
mass of station: approx. 140 metric tons = 280,000 kg
average orbital altitude: ~380 km orbital radius: velocity: ~7700 m/s
Mean motion: 15.70869555 rev/day
Decay rate: 1.60710E-04 rev/day^2
loses a kilometer a week altitude corresponds to an power loss of: ~(1/97745)*(0.5)*(280,000 kg)*(7700 m/s)^2/86400 seconds = 990 Watts call it a kW
to replace this power loss requires a force of F=Power/velocity
force needed: 1 kW/7700 m/s = 0.13 newtons
earth's magnetic field: approx. 1 gauss=10^-4 T
Force = 2piR*I*B*turns, R*I = 207 ampere*meters*turns
assume a desired voltage drop of 100 V, and that gives us I= 10 A assuming 100 turns this gives us a coil of radius 0.2 meters.
I would be surprised if the station did not have a spare kilowatt of power available. As far as aiming the coil so that the magnetic field is in the proper direction relative to the earths magnetic field, 3 coils could be used and power changed between the 3 to create the proper net field.
Sig cancelled due to lack of interest
Thanks for the great explanation Moofie. ;)
The problem is that the tethers get damaged by micrometeors. A small comparison graph of the degradation rate of single and interlinked tethers can be seen near the bottom of http://www.tethers.com/Hoytether.html. IMHO, this means that other (non-tethered) means of magnetic propulsion may be worth investigating, as there is nothing unique about the tethered geometry which makes it advantageous for magnetic propusion.