Comments on: Space Junk 1: Science 0

By: Science 1: Space Junk 0? | Cosmic Variance | Discover Magazine

Science 1: Space Junk 0? | Cosmic Variance | Discover Magazine — Sun, 01 Mar 2009 04:45:19 +0000

[...] due to the recent satellite collision. Naturally, those of us who know and love Hubble were a tad concerned about this latest development, which would probably have led to a complete shutdown of the [...]

By: Eugene

Eugene — Mon, 23 Feb 2009 02:01:05 +0000

Paul : hindsight is 20-20. More seriously, it’s kinda hard to design stuff “to be easily serviced with robots”, especially given the long timescale of space programs, you don’t really know what robots can do in the future.

By: Paul Murray

Paul Murray — Mon, 23 Feb 2009 00:36:19 +0000

How about designing future big expensive things so that they can easily be serviced with robots? You know – build it all out of meccano, supply it with some robots that can walk along and manipulate meccano. If something important gets damages, disassemble podule C (Prof Jones’ experiment – stuff him) and use the mecanno to rebuild something more important.

By: Kevin Conod

Kevin Conod — Sun, 22 Feb 2009 04:24:14 +0000

>Anyone yet contact Waste Management about a near-earth orbit week day junk pick-up >contract??

Has anyone contacted Adam Quark? I bet United Galaxies Sanitation would take the contract!

By: Low Math, Meekly Interacting

Low Math, Meekly Interacting — Sat, 21 Feb 2009 22:39:32 +0000

Check out the simulation near the bottom of this page:

http://www.soton.ac.uk/mediacentre/news/2009/feb/09_18.shtml

I’m assuming the collision that actually happened created a more extensive debris cloud.

By: Low Math, Meekly Interacting

Low Math, Meekly Interacting — Sat, 21 Feb 2009 22:31:10 +0000

I think what made this one particularly notable is that both objects were put up there in specific orbits deliberately, and even though one was defunct, and had probably drifted, both were intact, large, and presumably easily trackable. Yet no one had any idea this was going to happen, apparently. At the least, we can be pretty sure the Iridium people were clueless.

By: Eugene

Eugene — Sat, 21 Feb 2009 22:17:33 +0000

Just a couple of things from an ex-spacecraft engineer (turned physicist) :

1) the recent Iridium collision was *not* the first time an in-space accidental collision has occured. The first was in 1996, between a piece of some unidentified debris (believed to be jettison booster stage) and CERISE, a french microsatellite designed to listen to military chatter. The CERISE is gravity gradient stabilized, with a 4 meter long boom. The boom was chopped off in the collision, and the spacecraft started to tumble. But everything else on the spacecraft was still working, and mission controllers managed to stabilize it with active controls. I am partial to this because I actually worked in SSTL, who built CERISE.

2) Robotic repairs of Hubble. This is pretty nuts engineering wise. The difficulties that an actual astronaut faced to replace any item on the HST is enough to tell me that this robotic mission is probably wishful thinking by NASA at best, a smokescreen at worse. (On the other hand, if they are just going to fix those momentum wheels, they might be able to slap something quickly and dock it (somehow) with HST.

By: Low Math, Meekly Interacting

Low Math, Meekly Interacting — Sat, 21 Feb 2009 19:36:38 +0000

Thanks for the reminder, Stan.

By: Odani of the Senate

Odani of the Senate — Sat, 21 Feb 2009 05:06:42 +0000

Oh, there you scientists go again, exaggerating dangers and scare-mongering in general. Why, me & Ronnie look at the sky all the time and never see any space “junk”. If you scientist types didn’t insist that everything should travel at 17,000 miles per hour or faster then there wouldn’t be any problem at all. Want to fix the problem? Y’know, all we have to do is just cut taxes & then everything will be OK*

*well, we might want to fight a war or two, ‘specially if there’s lots of petroleum there.

By: Tony V MD

Tony V MD — Sat, 21 Feb 2009 03:27:23 +0000

I did a little reading on the Kessler syndroma and found it fascinating. My knowledge of nuclear physics is miniscule, but is anybody else reminded of sub-critical nuclear reactions in this scenario ?

By: coolstar

coolstar — Fri, 20 Feb 2009 23:01:10 +0000

Actually, if SM4 is cancelled and can’t be rescheduled, that’s pretty much the end of Hubble. There’s no chance a robotic mission can be put together in time ( even a try would likely end up being a very expensive boondoggle). Robert Zubrin made a pithy comment similar to Brian Mingus’s back when a previous NASA administrator (I won’t mention the doofus) had ruled ALL Hubble service missions verboten after the Columbia disaster.

By: Ciaobella

Ciaobella — Fri, 20 Feb 2009 21:55:15 +0000

NASA admins dragged their feet forever about fixing the Hubble and now they’re excited to have another excuse to postpone/cancel any servicing mission. They’d rather blow the entire budget on a worthless space tourist hotel and a worthless manned Moon/Mars program.

By: Brian Mingus

Brian Mingus — Fri, 20 Feb 2009 21:51:58 +0000

The first thing I was told in the Navy was that the ship comes before the sailors. Presumably the hubblenauts would be willing to go on the mission despite the possible deadly consequences and the real reason for delaying the mission is the cost of the shuttle.

By: Anon

Anon — Fri, 20 Feb 2009 21:23:04 +0000

Oh… you meant the Hubble… funny how you didn’t mention that name in the article
COS, WFC3, ACS, and STIC: expansion for early morning readers would be helpful.

By: Let It Snow « Cog and Helix

Let It Snow « Cog and Helix — Fri, 20 Feb 2009 20:09:15 +0000

[...] ahead as long as there is seen to be less than a one-in-sixty chance of debris hitting the shuttle. Cosmic Variance bets that if the mission is cancelled, Nasa might try sending robots instead. I’m not so [...]

By: Stan

Stan — Fri, 20 Feb 2009 19:38:28 +0000

You are thinking of Donald Kessler:

http://en.wikipedia.org/wiki/Kessler_Syndrome

By: Low Math, Meekly Interacting

Low Math, Meekly Interacting — Fri, 20 Feb 2009 17:27:39 +0000

It’s discouraging when you consider that any new technology designed to mitigate the existing problem (better “orbital hygiene” can slow its growth) is pretty much directly adaptable to space warfare, and hence will have a very difficult time getting implemented. Ground- or air-based laser? Anti-satellite weapon. Orbital interceptor? Anti-satellite weapon. You just know the first time one country starts work on this, even with total transparency, the rest of the space-faring world will flip out. Attempts at international collaboration will get nixed by the security hawks due to the fact NASA and/or the ESA would be sharing weaponizable technologies with the likes of Russia and China. Hell, in the wake of the Chinese “experiment”, I even had to wonder when I first heard about this whether or not it was deliberate.

Who was it that hypothesized a chain-reaction catastrophe in Earth orbit? The idea was collisions like this beget new collisions and the amount of debris increases exponentially up to a point that nothing up there is safe, and the Earth is surrounded by a chaotic halo of shrapnel.

I suppose that would foster a more collaborative approach to the problem.

By: Tbird49er

Tbird49er — Fri, 20 Feb 2009 16:23:25 +0000

Anyone yet contact Waste Management about a near-earth orbit week day junk pick-up contract?? Thursday’s would be good. Seems we humans always realize, belatedly, our own (wasteful) impact on our environment (including space!). Perhaps this concept will become as integral to our future planning as our basic desire to explore. Then again, woefully, probably not. With no traffic cops in space (read that as no cooperative/coordinative international planning of orbits/routes/space useage), periodic wrecks will be the inevitable result, raining down debris on our hapless existence.

By: Alberto

Alberto — Fri, 20 Feb 2009 16:01:11 +0000

- NASA is proceeding with plans for the STS-125 (SM4) servicing
mission to the Hubble Space Telescope in May 2009. A safety and
mission assurance review for SM4 is scheduled for April. An
in-depth analysis of all the risks, including the potential orbital
debris risk something assessed before every mission will be
considered at that time. NASA also will further assess debris
risk at the mission’s flight readiness review, held routinely
before each shuttle launch.

- The Hubble servicing mission team is confident the debris risk
will be acceptable for the flight, but it requires time for proper
analysis. Currently, the team does not have an updated risk
assessment for the STS-125 mission that includes the satellite
collision on February 10. A detailed analysis will be available
in mid-March to develop mitigating strategies, such as alternating
attitudes or adjustments to the planned spacewalks, if needed.
Here’s the official word:

- As NASA orbital debris experts continue to better define the
risks to our spacecraft resulting from the collision, the Hubble
servicing mission team will evaluate any potential additional risk
caused by the collision.

We hope this information helps ease any concerns you may have
about the effects of the collision debris on SM4. We’ll let you
know if new information becomes available, but for now you can
rest assured that this event has not resulted in any change of
plans for the servicing mission.

By: Reginald Selkirk

Reginald Selkirk — Fri, 20 Feb 2009 15:07:17 +0000

This would be a good opportunity for certain superpowers to realize that, just as with nuclear weapons in an earlier age, space-based warfare may have unknown deliterious consequences. We need a modern day Carl Sagan to step up to the plate and publicize this issue.