Friday, May 4, 2012

Space Junk-The Waste in space


Don Kessler, the creator of the said-to-be-famous “Kessler Syndrome” theory? In the late 70s, Kessler, a now retired NASA scientist, penned a seminal paper called: “Collision Frequency of Artificial Satellites: The Creation of a Debris Belt”. In it he wrote: “As the number of artificial satellites in earth orbit increases, the probability of collisions between satellites also increases. Satellite collisions would produce orbiting fragments, each of which would increase the probability of further collisions, leading to the growth of a belt of debris around the earth. This process parallels certain theories concerning the growth of the asteroid belt. The debris flux in such an earth-orbiting belt could exceed the natural meteoroid flux, affecting future spacecraft designs.”
Kessler used a mathematical model to project the rate at which the asteroid belt he described in his paper would form, and came to the conclusion that, given the right conditions, the debris-filled belt could form as early as this century.

Now, in earth terms you’d hardly call something that passed by you with kilometres to spare a miss, but in space a couple of kilometres is what one calls a close shave. Then there’s the fact that a NASA satellite fell to earth last year, and a Russian probe dropped out of the sky this year.

Photo: The Father of Space Junk, Donald Kessler. (Photo courtesy of Space Junk 3D, LLC.) 
But the problem isn’t so much space debris falling to earth because about 70% of the planet is water and smaller pieces of space junk invariably burn up on entry into earth’s atmosphere. The bigger pieces that do land from time to time are a bit of an issue. The real nightmare that’s keeping NASA awake at night, however, is the growing amount of space debris, and the potential for it colliding with the space station or an intergalactic private craft taking tourists into outer space.

A US non-profit science policy outfit, the National Research Council called on NASA to develop a formal strategy for tracking space junk, and to look at removing debris.

Read more here