European Space Agency Inheriting Huge Satellite, and Trouble to Match

"Huge Satellite Poses 150-Year Threat of Space Debris"
Space.com (July 26, 2010)

"In three years, the European Space Agency will become the owner of what is possibly the most dangerous piece of space debris circling the Earth for the next 150 years: the 17,636-pound Envisat Earth observation satellite.

"The space agency will take control of the Envisat satellite, which has been extended to 2013 and appears to set records wherever it goes.

"Launched in 2002, Envisat was the biggest non-military Earth observation satellite ever built. At $2.9 billion in today's dollars, it is one of the most expensive. Its mission is viewed as a success by its users, all the more so insofar as the original five-year mission has been stretched to 11 years...."

Envisat is a huge satellite, by today's standards: 26 by 10 by five meters. It's in a polar orbit that should keep it in orbit for another 150 years - most of it, anyway.

The problem is that near-Earth space is fairly crowded. Part of a Chinese vehicle nearly collided with Envisat once - but didn't, since Envisat was maneuvered away from the projected point of impact. When the satellite's retired, it won't be maneuverable: and it's hard to imagine 150 years going by without a collision.

Worse, Envisat includes an antenna farm that's delicate - it wouldn't take a very big piece of debris to knock something loose, creating even more debris in that area.

Apparently the ESA doesn't want to do what America did with Skylab: slow the thing down so that it reenters Earth's atmosphere and falls pretty much where controllers want it to.

Been There, Done That: Skylab, 1979

I think it may be that "pretty much where" that's got ESA worried. On July 11, 1979, Skylab was supposed to reenter Earth's atmosphere, burn up for the most part, with the larger pieces falling into a rather empty part of the Indian Ocean.

Pieces of Skylab overshot the target area, giving folks on the west side of Australia a sort of fireworks show. Happily, nobody seems to have been hurt. ("On This Date in 1979 - Skylab Reenters Earth's Atmosphere," About.com)

"Skylab Re-entry BBC News July 11, 1979 NASA"

dvdguy2011, YouTube (November 29, 2009)

"Skylab Re-entry BBC News July 11, 1979 NASA"

150 Years Ago, 150 Years from Now

150 years ago, in 1860:

• The internal combustion engine was cutting-edge technology
• Rockets were a semi-obsolete sort of weapon
• Edison's commercially-practical incandescent lamp was 19 years in the future
• An English translation of Jules Verne's "From the Earth to the Moon" (Charles Scribner's Sons, New York) wouldn't be published for another three decades
• Many generations would pass before there would be a European Space Agency discussing what to do with an outsize artificial satellite

One and a half centuries from now, in 2160, my guess is that Envisat will be of interest to historians: and maybe tourists. At the rate we're going, someone will have salvaged the thing by then, turned it into a tourist attraction, or maybe declared it a historical landmark. Spacemark?

Whatever happens - I'm pretty sure that it'll either be out of orbit, or controlled so that it will stay in orbit.

The idea of Envisat as a tourist trap or historic site isn't all that far-fetched. I've posted about the folks of the Lunar Legacy Project. They're pushing for making the Apollo 11 landing site, Tranquility Base, a recognized anthropological site - so that it will be preserved. (July 16, 2009)

I think the LLP has their work cut out for them. One of the better spots for a horizontal launch catapult on the moon isn't all that far from Tranquility Base - and port facilities are notorious for overrunning archeologically-interesting sites. (July 17, 2010)

More:

• "Humanity in Space: The Next Few Decades"
• "Humanity in Space: The Next Few Centuries"