Space debris poses big threat

Space junk created by humans’ space missions over the last six decades could cause significant damage on Earth as well as in space, Astronomer Stuart Grey of University College London warned.

The space race started with the launch of Russia’s tiny satellite Sputnik in 1957. It provoked the United States to launch Explorer I space mission soon after. Small chunks from the launch vehicles, objects falling off satellites or unintended collisions create space debris.

According to a new visualization by Mr. Grey, more than 500,000 bits in the size larger than a marble are now orbiting Earth at a very high speed. Explosion in a Chinese ballistic missile in 2007 added 2,000 more pieces to space junk. In 2009, a collision between two satellites added nearly 2,000 more.

While most the pieces are quite small, some pieces of debris in space are as large as a bus. A piece of space junk can cause a big damage when it falls on Earth, particularly in a crowded area. It can also jeopardize satellites currently in orbit and future launches.

The International Space Station (ISS) once suffered a bullet-sized hole in one of its solar panels when a piece of space debris struck it. The problem has already forced space agencies to adjust orbits of their satellites in order to avoid any such collision.