Monday, April 21, 2008

Shocking Space Debris Images


The German newspaper Frankfurter Allgemeine Zeitung (FAZ, German only) today published an article on space junk. The shocking image is an eye opener. Humankind continues to repeat the mistake of strewing waste into common spaces (no pun intended) without a thought to the consequences, leaving costs we don't want to pay today for the future generations. The FAS article spurred our curiosity, leading us to find even more spectacular video and potential solutions to the problem (overleaf).

The ESA Space Debris Accumulation video depicts the tragic build up of space debris from 1957 through 2000. According to ESA's resident space debris expert, Walter Flury, the 10,000 pieces of space litter catalogued at the end of 2003 break into the following categories:

  • 41% -- miscellaneous fragments

  • 22% -- old spacecraft

  • 13% -- mission related objects

  • 7% -- operational spacecraft

  • 7% -- rocket bodies
Doing the math, that is 93% pure junk and only 7% useful satellites circling the earth. More disturbing, 50,000 uncatalogued objects larger than 1 cm (the largest size which modern shielding can likely deflect) are estimated to be spinning through space at hypervelocities.

Real Damage from Space Debris

So what, you say? There is a lot of space in Space...the images probably make it appear worse than it really is. Statistically, destructive collisions with operational satellites are predicted on average once every ten years. Nonetheless, as the image at left shows, the risk of damage is real. This hole over 1 cm in diameter penetrates the Hubble high gain antenna dish (the unit continued working in spite of the damage). The windows on the Space Shuttle have been replaced 80 times due to impacts with objects of less than 1 mm. And costly systems to track and issue daily emails warning of potential impacts must be maintained. The future impacts must also be considered. Space debris would be a severe hindrance to space-based solar projects. Last, but not least, there is the risk of space junk raining down on us: space junk hitting an Oklahoma woman is one of Space.com's top ten most memorable pieces of space junk .

Graveyards in Space

So what can be done? Guidelines do exist, published by the Inter-Agency Space Debris Coordination Committee (IADC). The guidelines limit creation of debris in normal operations, and promote "disposal" either by deorbiting junk back towards earth, where it usually burns up in the atmosphere, or by putting space junk into "graveyard" orbits above the commercially important low-Earth and geostationary orbit zones. But more needs to be done. Some experts advocate for regulations. Live Science takes it a step farther, speculating on giant NERF balls, space lasers and cosmic collection vehicles among other imaginative ways to tackle the growing problem.


Via ::Frankfurter Allgemeine Zeitung and European Space Agency

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