No space for junk
No space-walking astronaut this, but a Russian spacesuit spinning slowly in Earth?s orbit. The radio-equipped apparel was tossed overboard last weekend from the orbiting International Space Station to see if it could function as a satellite, transmitting telemetry data to the ground.india Updated: Feb 06, 2006 01:39 IST
No space-walking astronaut this, but a Russian spacesuit spinning slowly in Earth’s orbit. The radio-equipped apparel was tossed overboard last weekend from the orbiting International Space Station to see if it could function as a satellite, transmitting telemetry data to the ground. If successful, scientists hope to have more such ‘SuitSats’ soon. This, alas, is anything but a good idea, given the amount of man-made debris circling Earth. ‘Space junk’ poses an increasing threat to space activities, including robotic missions and human space flight.
Since the first satellite, Sputnik, was launched in 1957, thousands of space probes, satellites and telescopes have been put into orbit. This has resulted in a growing junkyard of hardware like nuts and bolts, nuclear reactor cores and solid fuel fragments. This silently moves around Earth. Be it the US satellite, Vanguard 1, which has been in space since March 1958 (making it the oldest piece of space trash), or the glove that the first American spacewalker, Ed White, dropped in 1965 (it orbited Earth for a month at 18,000 miles an hour, becoming the most dangerous garment in history!), space trash moves fast, often at speeds touching 25,000 miles an hour. So, even tiny pieces can cause extensive damage: paint flakes whizzing in at such velocities, for instance, can rip holes in spacecraft.
To avoid explosions that could send fragmented trash hurtling through space, no fuel is left behind on abandoned satellites. But researchers reckon that even without new launches, the number of space fragments created by collisions would still exceed the number falling back to Earth by 2055. In fact, all satellite-based technology will be hit much before. So it’s time to clean up the litter. But ground-based lasers to alter dead satellites’ orbits, ion engines to prompt new satellites to dive back faster into the atmosphere at mission-end and electrodynamic tethers that increase drag are all still on the drawing board. The best solution obviously is to skip Earth orbit if possible. After all, many functions of orbiting satellites can easily be handled by Earth-based fibre-optic systems. Time to explore these if we want to maintain near Earth space as a door to the future — to planets and stars — and not a junkyard.
First Published: Feb 06, 2006 01:39 IST