Largest Ever Piece of Space Station Junk to Hit Earth Tomorrow
Written by Ian O'Neill
The Early Ammonia Servicer (EAS) photographed on July 23rd, 2007, by ISS astronauts. Watch your heads, it's re-entering tomorrow! (NASA)
The EAS was dropped from the International Space Station in 2007, making it the largest piece of space junk ever dropped from the orbital outpost. At the time, it was believed the ammonia coolant-filled debris would only stay in orbit for 300 days; alas this was a huge underestimation, the EAS has been in orbit for 15 months. The final hours of the large chunk of space debris are being closely tracked by NASA and the U.S. Space Surveillance Network as a precaution. Although no bits of the EAS are expected to pose a danger to people on the ground, NASA's space station program manager said "we just need to be cautious."
The EAS was installed on the space station during a spacewalk by the crew of Discovery in 2001 during the STS-105 servicing mission. It was installed as part of the station's emergency reserve coolant system, but when the mature thermal control system was activated, the EAS became surplus to requirements and NASA had to devise plans to remove the equipment. At the time, this posed a tricky problem – after all, you can't just throw junk overboard, what happens if it creates a future hazard for the ISS or other orbiting craft?
Eventually a solution was found. Astronaut Clay Anderson led a 7 hour 41 minute EVA with cosmonaut Fyodor Yurchikhin and robotic arm operator Oleg Kotov to throw the EAS overboard, toward the Earth on July 23rd, 2007. They did this just before a re-boost by the Soyuz spacecraft docked with the station at the time. By doing this, the EAS assumed a slowly deteriorating spiral orbit toward Earth whilst the space station increased its altitude, avoiding any possibility of encountering the discarded EAS on future orbits.
In July, I reported that the EAS had reached an ideal altitude for astronomers to catch a glimpse of it through their telescopes. The speedy +4 to +4.5 magnitude object had been spotted by many amateur astronomers.
Any observation opportunities are about to come to an abrupt end, however. Some time on Sunday, the EAS will succumb to atmospheric drag and drop toward the ground. As to whether any debris from the re-entering EAS will hit the ground, NASA believes that up to 15 pieces of the ammonia storage tank might survive the high temperatures. The pieces are predicted to range in size from 40 grams (1.4 oz) to 17.5 kg (40 lb). It is most likely these pieces will land in the ocean, but if any of the debris hits solid ground, they will be travelling at 160 km/hr (100 mph).
It is unlikely that any part of the EAS will be a risk to people or property, but Mike Suffredini, NASA's space station program manager, warns, "If anybody found a piece of anything on the ground Monday morning, I would hope they wouldn't get too close to it." After all, should any of the toxic ammonia stored inside the EAS survive re-entry, it could pose a health risk. (Having said that, I would think a man-made meteorite travelling at 100 mph would also be considered a "health risk," let's just hope re-entry occurs over 2/3 of the planet covered with water…)
Update: According to SpaceWeather.com, little is known about where the EAS will re-enter the atmosphere, "At the moment, every continent except Antarctica has some favorable ground tracks." We had a much better idea as to where and when asteroid 2008 TC3 hit Earth, perhaps we need to tighten up on the space junk re-entry problem (although I'd expect it's much harder to predict the upper atmospheric dynamics than orbital trajectories of incoming meteoroids).
Filed under: Space Station
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November 1st, 2008 at 2:36 pm
Well…. I'm so glad that NASA has our best interest in mind. Seems to me they are still rolling the dice with safety. In all actuality, I kinda want someone to get hit with debris, or maybe just their car. I'm curious as to what kind of lawsuit would arise, and if NASA would admit guilt. I'm guessing they'd treat it like the airlines do when blue ice falls from the sky and hits some ones roof. Basically deny it all. Odds are very low, I know, but Murphy's Law says it will come to pass one day for sure.
November 1st, 2008 at 2:42 pm
"and it's going to drop through the atmosphere some time tomorrow (Sunday, Oct. 2nd)."
Unless this news is actually from last month, this date should say Nov. 2nd instead of Oct. 2nd.
November 1st, 2008 at 2:48 pm
Thank you Michael for catching that… I seem to be a month behind the rest of the world. Corrected now
Cheers, Ian
November 1st, 2008 at 5:52 pm
I think it is rather sad (read:stupid, pathetic) that they don't know where the thing will hit the air and eventually land.
We can track entire planets*, stars* and galaxies*, yet something right outside our atmosphere, incredibly close to satellites (of which i'm sure there are many last time i checked), we can't even track it…
If i get hit by anything and die, I will be sorely pissed off NASA!
* as far as we know.
November 1st, 2008 at 6:04 pm
Its a relatively small piece of machinery that was junked in a way not originally intended. It was never designed to orbit on its own and this is not exactly a controlled descent they've set it on.
Trying to predict its flight characteristics while the things scraping against the upper atmosphere… thats gotta be a nightmare.
That they can estimate the drag enough to figure out which month it will fall in is impressive enough.
November 1st, 2008 at 10:23 pm
Isn't there something we can come up with to force entry in a specific timeframe? Something cheap and disposable that could be attached to the object and would just give a good push every so often when lined up correctly? Seems to me that every large orbiting object should have a form of disposal insurance like this.
November 2nd, 2008 at 3:31 am
Some readers seem puzzled as to why we cannot predict the re-entry time of this gadget. Well, there are several reasons here…
First – look at the shape of the thing. It has something like a 2:1 aspect ratio. It will have twice the resistance if it is face on rather than edge-on. The resistance it gets will depend on its exact attitude, and spin, and these in turn will also alter its attitude and spin. The other thing is the edge of the earth's atmosphere. This is not a uniform sphere. It has wisps and bulges. As you re-enter, you do not feel a smooth deceleration as you might expect from a very thin gas, but a series of slams.
The re-entry policy sound. The unwanted lump of stuff has been pushed into an orbit where it will encounter enough of the upper atmosphere to slow it down and re-ender in a year or so. It is not going to stay up there. It is not using some separate rocket that would have to be carried up into space with it, and then have all the risks of perhaps not working as planned. The device is staying as one big lump so it is easy to track. Simple is good.
November 2nd, 2008 at 3:59 am
so we're all hoping it has a good attitude then and isn't ticked off!
November 2nd, 2008 at 6:57 am
I'm partial to an idea from the anime Planetes, where characters used programmable hand mounted thrusters to junk their junk.
I could see them making a lunchbox sized device that can deorbit machinery like this and/or help us track it better.
Of course you'd have to devote storage space to the things in advance, and theres no telling what could happen if one malfunctions and boosts crap in the wrong direction.
Maybe they could have duct taped it to an outgoing Soyuz service module… but then there would be safety issues. Not to mention that these ships were not designed to maneuver with external loads.
The only reasonable solution seems to be what we do now. Let low earth orbit clean itself and try our best to stay out the way.
November 2nd, 2008 at 8:06 am
"Funny thing is, we don't know where, and we don't precisely know when." I thought we had scientists. Sounds like a high school science club is in charge here. How sad.
And again I say: What A Waste!!! What was the cost to build this? What cost to put it up there? And now we just haphazardly throw it away in a way that could cause harm. Next week we will see some news report about funding for space being cut but instead of being upset I will just say "if only we had used our resources more wisely…".
It used to be humans on the ground sending monkeys into space. Somehow that got reversed.
Come on Space X, show us how it should be done.
November 2nd, 2008 at 8:28 am
Universe Today readers should be advised that they can greatly reduce the danger of being hit by a fridge by simply glancing upwards from time to time and wearing a hard helmet.
November 2nd, 2008 at 8:53 am
I witnessed something exploding overhead with light trails behind it imediately afterward on 11-1-08 at approx. 1:00am eastern time over michigan skys. Whatever it was lit up the entire sky like a flash bulb. It was so bright I had to blink a couple of times after. I stayed up a little while and did see another flash but much smaller than the first. Did anyone else witness this?
November 2nd, 2008 at 8:54 am
Before whining about how badly scientists are doing at plotting this things trajectory and reentry plan, go for a drive down the free way and huck a half empty milk carton out the window, but before you do it, you need to find a target on the ground, you get no trial run, and you need to do it *Right Now*.
November 2nd, 2008 at 10:31 am
so, um, why would the pieces only be traveling 100mph? That should depend on the surface area of the pieces, and the mass.
November 2nd, 2008 at 12:30 pm
I don't understand. Could this not have come down in a more controlled way? Like with a retro rocket that would assure it comes down, say in a lonely part of the Indian Ocean?
i dunno
November 2nd, 2008 at 1:36 pm
Do you guys understand how improbable any harm from this thing is? Even objects as massive as Skylab and Columbia (the latter coming apart over the central US, no less) managed not to hurt anyone on the ground.
As for lawsuits, The Outer Space Treaty, which the US is a signatory to, makes the launching government liable for any of its stuff that comes down in any other country. That's clear. Though it took some teeth pulling, the Soviet Union, for example, did pay Canada for the cleanup of radioactive remnants of Cosmos 954, for example.
No, we can't put a retro rocket on every single piece of debris (the only solution is to get better at not creating the stuff, which resents a far greater hazard to *other* objects in orbit), no, no one is even going to pay what SpaceX would charge to launch something (and that 'something' would not be theirs, it would be just another customer payload) to rendezvous with everything, and when something *is* de-orbited in a controlled manner (Jules Verne), someone *still* objects…
And remember, about 70% of this planet is *still* covered with water. The odds of surviving pieces, if any, doing anything but joining assorted megatons of ships on the sea bottom are still pretty good…
Even the position of planets, stars and galaxies can't be determined with infinite precision, and this object is likely to tumble and present drag in unknowable, chaotic ways. Indeed, a tumbling re-entry is *more* likely to assure desruction than one that is not.
You can expect more of this, when the Shuttle (and its superior downmass capability, compared to Orion) leaves service.
November 2nd, 2008 at 4:56 pm
It stated they are tracking it.
"The final hours of the large chunk of space debris are being closely tracked by NASA and the U.S. Space Surveillance Network as a precaution. Although no bits of the EAS are expected to pose a danger to people on the ground, NASA's space station program manager said "we just need to be cautious."
They why can they not tell us where it's going to hit if and when? They have to have some idea. The point is they do have an idea and really worried about right now.
Looks like they would give everyone a heads up! I'll be watch the sky tonight!!! Would be something to see!
November 2nd, 2008 at 7:02 pm
Hear hear.
Quite frankly, this constant "what a waste" whining gets really tiresome. The only way to deal with space junk the way you seem to want it dealt with implies a massive orbital infrastructure, including a junkyard, with at least a few fuel plants installed in ice-rich near-Earth asteroids or comets. That's the only way to have the fuel needed to send the junk back and forth until it gets recycled, and/or, deorbit everything in a controlled fashion. While we're at the stage of having no industrial infrastructure whatsoever beyond Earth we simply cannot allocate the resources needed to do that. Someday, yeah, we might be able to do it. But now? Absolutely no way.
Going up to orbit is not simply a question of intercomming to Scotty to beam you up (preferably with your clothes on). In real life, things are much, much more complicated than that.
November 2nd, 2008 at 7:27 pm
I saw a bright flash like something exploding or burning up in the sky.
Then I heard a loud rumble.
Then it rained.
November 2nd, 2008 at 8:34 pm
Its too expensive to collect the garbage, move the garbage, or even store the garbage properly. So we abandon it where it is and thats simply how it has been.
This unpredictable situation is the result.
Obviously if we're going to be flying more payloads and working in orbit (generating more garbage) the status quo wont do.
There has to be a more refined way to junk things than to wait for a half billion dollar launch of the shuttle or giving it the heave-ho overboard.
November 3rd, 2008 at 12:46 am
Spaceweather.com now reports that the EAS hasn't reappeared on sky-watching cameras for the past two days, implying that it has likely already re-entered in a remote location.
November 3rd, 2008 at 6:14 am
I think it is rather sad (read:stupid, pathetic) that HUNNTER cannot open up a few books or take some courses to find out exactly why it is so difficult to project the time/place of this objects entry into the atmosphere…
Amazingly he has no problem criticizing others with his own self-imposed ignorance. Which actually makes him even more pathetic.
In an attempt to decrease your patheticism know this: The atmosphere expands and contracts, and while we do have an idea approximately where that point is w/n a kilometer or so right now, it is rather hard to predict it days in advanced, and it isn't exactly a consistant point all the way around the planet.
This object is moving around 18,000 mph. So being off just a bit means thousands of miles… not to mention the fact, gathering data on all dimensional points can get a bit mind boggling.
The orbit is deteriorating very slowly and not exactly consistantly… which also brings up the possibility that it may skip off the atmosphere a bit before it slows up enough to fall, or it could just 'dig in' and drop/slow down quicker than expected.
I could go into more specifics, but obviously you aren't ready for it.
November 3rd, 2008 at 7:59 am
I guess no one was paying attention, but instead arguing about space juck. Again I want to know if there were any CREDIBLE witnesses to what I witnessed on 11-01-2008 at approx. 1:00am EST. over Michigan skys. There was a flash of light like a flash going off that lit up the entire area where I am at. I noticed a trail of light immediately afterward. Was this nasa's spacer junk or something else? If there is any credible witnesses or astronomy professionals out there that did witness this, then I would like to hear from. By the way, it was a nice starry night here in Michigan. For all of the other skiptics, go whine on some other website.
November 3rd, 2008 at 8:19 am
MikeM-You probably did not see the EAS — it is reported to have reentered Earth's atmosphere on Sunday at 10:51 p.m. CST, mostly disintegrating in the process but likely impacting about 15 pieces with the Southern Ocean, just south of Tasmania, between Australia and New Zealand.
November 3rd, 2008 at 2:23 pm
Funny you should mention that MikeM my google search looking for what came crashing through the clouds of the Ann Arbor area lead me to this forum. This took place however at about 7:30pm ish.
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