Space Junk

Collision Risks

Space junk poses significant collision risks to operational satellites and spacecraft. Gary Arndt explains that objects in orbit travel at speeds of at least 17,000 mph, making even small debris potentially catastrophic 1. The International Space Station, for instance, must maneuver at least once a year to avoid debris 1.

The shuttle Endeavor was hit by an object so large that its radiator looked like it was hit with a bullet.

--- Gary Arndt

Historical incidents, such as the 2009 collision between the Cosmos 2251 and Iridium 33 satellites, have only exacerbated the problem by creating thousands of new debris pieces 1.

   

Kessler Syndrome

The Kessler syndrome describes a scenario where collisions between space debris create a cascade of further collisions, rendering low Earth orbit unusable. Gary Arndt notes that this phenomenon was hypothesized by NASA scientist David Kessler in 1978 2. The increasing number of satellites exacerbates this risk, making it crucial to develop deorbiting strategies for new satellites and address existing debris.

This problem of junk causing collisions, which then creates exponentially more junk, risks something called the Kessler syndrome.

--- Gary Arndt

Proposals to mitigate this issue include using tethers, magnets, foam balls, and lasers to remove debris, as well as international treaties to govern space activities 2.