Space pollution pertains to the accumulation of manmade debris in outer space. Approximately 500,000 debris pieces, commonly referred to as "space junk," are tracked by the National Aeronautics and Space Administration, or NASA. The buildup of space junk orbiting the Earth presents an alarming threat to satellites, spacecrafts and the people living on the planet.
The exploration of space is the progressive observation and investigation of celestial phenomena and the physical structures comprising the universe. Through technological advancements, safe access to space has become vital in many aspects of modern living. Artificial satellites, such as weather, communications and military satellites, are placed into orbit around Earth primarily to gather data. Without these artificial celestial bodies, life on the planet would be drastically affected.
Space ventures are made possible by the use of unmanned probes and human spaceflight. However, old space probes, satellites and other space vehicles that are no longer functioning often create space junk. The continuing increase in space rubble poses serious collision threats that may potentially destroy functional satellites, space shuttles and manned spacecrafts. The average speed of space junk is approximately 17,500 mph. On impact, small pieces of junk may only cause surface abrasion, while larger pieces of debris may completely destroy a satellite or spacecraft.