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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???
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".
Actually, the Earth's atmosphere extends out to roughly 2000 kilometers or so. Spacecraft orbiting within 2000 kilometers are slowly spiraling in, due to the the tiny amount of air resistance.
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~ |rip/\/\aster /\/\onkey
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
Reading the summary makes me think either the PR firm who wrote it doesn't understand acceleration, or expects us to be unable to.
The orbit could currently be decaying at 1km/wk, but that is less useful than saying the paperclip I just dropped is currently traveling at 15m/s.
In order to convey the predicament of the ISS the article should mention altitude, downward velocity, and acceleration.
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.
They are in LEO, Low Earth Orbit, with emphasis on Low. So yes, there is some drag from the "atmosphere".
The mistake you're making is to think there's some sort of sharp dividing line between "atmosphere" and "space". NASA defines "space" as beginning about 50 miles above the earth, but traces of atmosphere extend well above that.
Why aren't the standard units being quoted
e +per+week+in+furlongs+per+fortnight&meta=
It's a rate of 9.94193908 furlongs per fortnight
http://www.google.co.uk/search?hl=en&q=1+kilometr
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.
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!
A better way to think about it is in terms of forces, not velocities. In order for an object to travel in a circle, there must be an inward-directed force, a centripetal force. Imagine you're swinging a ball on a string around your head. The ball travels in a circle because the string is continually applying an inward-directed force to it. For an object in orbit, this inward-directed force is gravity.
The image of the craft continually "missing" the Earth is not as useful, because the size of the Earth really isn't relevant to the question of orbit -- only its mass is. An object can orbit whenever its speed is less than the escape velocity. It's just that some orbits, unfortunately, intersect with the surface of the Earth.
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.
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.
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.
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)
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.
not entirely due to gravity though gravity is certainly involved.
an orbiting object has its lateral velocity balanced with gravity in such a way that its state stays steady, but atnospheric resistance takes away energy from the object causing it to spiral into lower and lower orbits (and as the orbit gets lower the resistance gets greater accelerating the process).
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register