Comments on: What if the Earth had rings? http://boingboing.net/2010/09/15/what-if-the-earth-ha.html Brain candy for Happy Mutants Tue, 21 May 2013 12:15:00 +0000 hourly 1 http://wordpress.org/?v=3.4.1 By: Anonymous http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886294 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-886294 wgmleslie, you beat me to it. Planetes was a whole series premised on space junk. One of the most clever titles ever (ancient greek for wanderers, which became our word for planets, but the title also refers to the characters). The intro alone packs more space history than your average documentary. http://www.youtube.com/watch?v=XRM585MVvyA wgmleslie, you beat me to it. Planetes was a whole series premised on space junk. One of the most clever titles ever (ancient greek for wanderers, which became our word for planets, but the title also refers to the characters). The intro alone packs more space history than your average documentary.

http://www.youtube.com/watch?v=XRM585MVvyA

]]> By: mdh http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886097 mdh Wed, 30 Nov -0001 00:00:00 +0000 #comment-886097 My imagination says there is more potential energy in a piece of cm sized space junk at orbital speeds then in a hand grenade. Is there a physicist in the house? My imagination says there is more potential energy in a piece of cm sized space junk at orbital speeds then in a hand grenade.

Is there a physicist in the house?

]]> By: wgmleslie http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886101 wgmleslie Wed, 30 Nov -0001 00:00:00 +0000 #comment-886101 <a href="http://en.wikipedia.org/wiki/Planetes">Planetes.</a> Planetes.

]]> By: jordawesome http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886110 jordawesome Wed, 30 Nov -0001 00:00:00 +0000 #comment-886110 What if the Earth Had Rings? http://www.universetoday.com/45653/what-if-earth-had-rings/ What if the Earth Had Rings?

http://www.universetoday.com/45653/what-if-earth-had-rings/

]]> By: lewis stoole http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886623 lewis stoole Wed, 30 Nov -0001 00:00:00 +0000 #comment-886623 it had better be pretty after all of the money we spent getting that junk up there. it had better be pretty after all of the money we spent getting that junk up there.

]]> By: Anonymous http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886114 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-886114 it's the relative speed that matters, not the overall speed of an object. If I'm moving 16999 mph and something moving 17000 mph in the same direction hits me, i won't even feel it unless it's a large object. It certainly won't puncture anything durable. Anything going significantly slower or faster will find itself in a different orbit fairly quickly, and as far as I know, all that garbage is orbiting the earth in the same direction. in short; it's not quite as bad as they make it sound. it’s the relative speed that matters, not the overall speed of an object. If I’m moving 16999 mph and something moving 17000 mph in the same direction hits me, i won’t even feel it unless it’s a large object. It certainly won’t puncture anything durable. Anything going significantly slower or faster will find itself in a different orbit fairly quickly, and as far as I know, all that garbage is orbiting the earth in the same direction.

in short; it’s not quite as bad as they make it sound.

]]> By: efergus3 http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886115 efergus3 Wed, 30 Nov -0001 00:00:00 +0000 #comment-886115 The bad news is, it will once the moon enters the Roche limit and gets torn apart. The good news is that this won't happen before Xmas. The bad news is, it will once the moon enters the Roche limit and gets torn apart. The good news is that this won’t happen before Xmas.

]]> By: TheMadLibrarian http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886647 TheMadLibrarian Wed, 30 Nov -0001 00:00:00 +0000 #comment-886647 If someone comes up with a viable way to clean out space junk from valuable orbital real estate, I'm investing! If someone comes up with a viable way to clean out space junk from valuable orbital real estate, I’m investing!

]]> By: Anonymous http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886143 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-886143 The moon will never enter the Roche limit. The moon's orbit actually is getting farther away from the Earth at 4 centimeters per year. The moon will never enter the Roche limit. The moon’s orbit actually is getting farther away from the Earth at 4 centimeters per year.

]]> By: BookGuy http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886401 BookGuy Wed, 30 Nov -0001 00:00:00 +0000 #comment-886401 The writer Junot Diaz has often said that pollution makes New Jersey's sunsets some of the most striking around. By extension, a planetary ring made out of pollution and garbage should be quite stunning. At least from the ground. The writer Junot Diaz has often said that pollution makes New Jersey’s sunsets some of the most striking around. By extension, a planetary ring made out of pollution and garbage should be quite stunning. At least from the ground.

]]> By: pjcamp http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-887183 pjcamp Wed, 30 Nov -0001 00:00:00 +0000 #comment-887183 There is a physicist in the house, and it isn't the speed that is important, it is the relative speed. Two objects in nearly the same orbit have nearly the same speed so the relative speed is nearly zero and the collision is not nearly so catastrophic. The issue comes in when an object is in an elliptical orbit that intersects another orbit. Then, when they meet, they aren't travelling at anything close to the same speed and collisions can be quite violent. The question about the energy content compared to a hand grenade therefore has no real meaning since the absolute velocity of the projectile is irrelevant to computing the energy of the collision. Unless you know the absolute velocity of both object, or their relative velocity, you can't say. There is a physicist in the house, and it isn’t the speed that is important, it is the relative speed. Two objects in nearly the same orbit have nearly the same speed so the relative speed is nearly zero and the collision is not nearly so catastrophic.

The issue comes in when an object is in an elliptical orbit that intersects another orbit. Then, when they meet, they aren’t travelling at anything close to the same speed and collisions can be quite violent.

The question about the energy content compared to a hand grenade therefore has no real meaning since the absolute velocity of the projectile is irrelevant to computing the energy of the collision. Unless you know the absolute velocity of both object, or their relative velocity, you can’t say.

]]> By: RedShirt77 http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886170 RedShirt77 Wed, 30 Nov -0001 00:00:00 +0000 #comment-886170 Weren't both satelites traveling at 42,100 kilometres per hour? Wouldn't the collision just be the difference in their vectors? maybe a few 1,000 kph? Weren’t both satelites traveling at 42,100 kilometres per hour?

Wouldn’t the collision just be the difference in their vectors? maybe a few 1,000 kph?

]]> By: Anonymous http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-887235 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-887235 I'm surprised that the commenters who mentioned Planetes didn't mention the technical term for the "futuristic 12-car pileup": <a href="http://en.wikipedia.org/wiki/Kessler_Syndrome" rel="nofollow">Kessler Syndrome.</a> I’m surprised that the commenters who mentioned Planetes didn’t mention the technical term for the “futuristic 12-car pileup”:
Kessler Syndrome.

]]> By: Lissamphibia http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886229 Lissamphibia Wed, 30 Nov -0001 00:00:00 +0000 #comment-886229 Space Junk Song! http://www.youtube.com/watch?v=6Fy7psIuJjc Space Junk Song!

http://www.youtube.com/watch?v=6Fy7psIuJjc

]]> By: valdis http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886750 valdis Wed, 30 Nov -0001 00:00:00 +0000 #comment-886750 Iridium 33 got nailed at pretty much a right angle, so the relative velocities was pretty close to sqrt(2)*orbital. http://en.wikipedia.or/wiki/File:Collision_iridium33_kosmos2251.jpg Now, if a 1cm chunk is a hand grenade, then a car sized satellite at sqrt(2)*orbital is.... And that's why there's hundreds of thousands of fragments. Iridium 33 got nailed at pretty much a right angle, so the relative velocities was pretty close to sqrt(2)*orbital.

http://en.wikipedia.or/wiki/File:Collision_iridium33_kosmos2251.jpg

Now, if a 1cm chunk is a hand grenade, then a car sized satellite at sqrt(2)*orbital is….

And that’s why there’s hundreds of thousands of fragments.

]]> By: Anonymous http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886241 Anonymous Wed, 30 Nov -0001 00:00:00 +0000 #comment-886241 Better space junk song: http://www.youtube.com/watch?v=M0Z4pj88evY Better space junk song:

http://www.youtube.com/watch?v=M0Z4pj88evY

]]> By: Avram / Moderator http://boingboing.net/2010/09/15/what-if-the-earth-ha.html#comment-886261 Avram / Moderator Wed, 30 Nov -0001 00:00:00 +0000 #comment-886261 Will the rings at least be pretty? Will the rings at least be pretty?

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