With all the satellite collisions, there is now a large debris field orbiting Earth. This debris field is perhaps more dangerous than any single intact object because of the increased chance of potential collisions from multiple debris objects. Several large satellite collisions have already been recorded, and these events have exacerbated the space junk problem.
In 2009, the satellites Iridium 33 and Kosmos 2251 collided at a speed of 42,000 kilometers per hour (26,000 mph) while in low Earth orbit (approximately 800 kilometers (500 mi) above the planet’s surface). Both satellites were destroyed by the collision.
So, instead of having two large objects orbiting Earth, we now have approximately 1,000 objects larger than 10 centimeters (4 in) that threaten many other satellites. (There are also many smaller pieces.)
Although about half the debris from the 2009 accident has now burned up in the atmosphere, several other collisions have occurred. Scientists estimate that the Iridium-Kosmos accident, along with China’s intentional destruction of a satellite by long-range missile in 2007, has doubled the number of dangerous and potential collision objects in orbit.