The space around Earth is a crowded space packed with nearly 22,000 spent rocket stages, dead or dying satellites and countless crumbs of human-made orbital flotsam. An average of one object has reentered Earth's atmosphere every day. <p>Here are 10 of the most memorable manmade things that have rained down on us.
The U.S. Navy intercepted its defunct spy satellite USA-193 on Feb. 20, 2008, sending a <a href="http://www.space.com/news/080221-sat-shoot-spot.html">trail of debris</a> that some amateur astronomers reported falling over the northwestern United States and Canada. Department of Defense officials said they hadn't recovered any debris larger than a football.
A woman in Turley, Oklahoma, got a noggin-knock in January 1997 when she was struck with a lightweight fragment of charred woven material. She was not injured. The <a href="http://www.space.com/news/ap_070328_spacejunk_jet.html">sky junk</a> was identified as debris from a Delta 2 booster, which reentered the Earth's atmosphere on Jan. 22, 1997. Other debris from that booster included a steel propellant tank and a titanium pressure sphere.
Several mysterious spheres turned up in Australia in the 1960s, with some speculating these balls could be connected with <a href="http://www.space.com/top10_alienencounters_debunked.html">UFO phenomenon</a>. One such titanium sphere was spotted in Merkanooka, Western Australia. Dubbed the Merkanooka ball, the metal sphere was later identified as a tank used for drinking water in the Gemini V spacecraft, which was launched on Aug. 21, 1965, and reentered the atmosphere and splashed down into the Atlantic Ocean on Aug. 29 that year.
A secret Soviet-navy satellite called Cosmos 954, which was launched on Sept. 18, 1977, spiraled out of control. The spy radar antennas each sported a compact nuclear reactor, making the reentry one of the most frightening to date for people on the ground. On Jan. 24, 1978, <a href="http://www.space.com/news/spacehistory/dangerous_reentries_000602.html">Cosmos 954</a> reentered over Canada and shed debris across the frozen ground of the Canadian Arctic. Following the crash, the U.S. and Canada conducted overflights of the area and associated cleanup efforts.
On Jan. 21, 2001, a <a href="http://www.space.com/missionlaunches/sfn-071205-delta2-countdown.html">Delta 2</a> third stage, known as a PAM-D (Payload Assist Module-Delta), reentered the atmosphere over the Middle East. Its titanium motor casing, weighing about 154 pounds (70 kilograms), slammed down in Saudi Arabia, while a titanium pressurant tank landed near Seguin, Texas, and the main propellant tank plunked down near Georgetown, Texas.
In May 1966, spacecraft debris was spotted in the Rio Negro District of Brazil. The metal parts were identified as coming from a stage of the Saturn development test (SA-5) that launched in 1964 and which reentered the atmosphere on April 30, 1966. The <a href="http://www.space.com/missionlaunches/070530_exp15spacewalk.html">litter</a> included a piece of lightweight metal, an oval-shaped chunk of metal, a black beehive-shaped structure and four pieces of fragile wire.
On Feb. 1, 2003, during its return to Earth, <a href="http://www.space.com/columbia/">Space Shuttle Columbia</a> disintegrated on reentry, killing seven astronauts. The catastrophic, lethal accident shed thousands of pieces of debris across a 28,000 square mile (72,520 square kilometers) area in eastern Texas and western Louisiana. More than 80,000 recovered pieces were stored for follow-up research.
After completing 51,658 orbits around Earth, the Compton Gamma Ray Observatory was <a href="http://www.space.com/scienceastronomy/astronomy/compton_deorbits_000604.html">intentionally deorbited</a> due to a crippled gyroscope on June 4, 2000. As the spacecraft tumbled through Earth's atmosphere, its solar panels and antennas were thought to pop off first, while other parts likely melted. About 13,227 pounds (6,000 kilograms) of debris from the observatory splashed down into the Pacific Ocean southeast of Hawaii.
In the world of space litter, the heavyweight champ would have to be Mir, heftier in its day than any object (except the moon) to orbit Earth. The 15-year-old <a href="http://www.space.com/news/cs-080110-hallfame-astronauts.html">Russian space station</a> began its suicidal nosedive on March 23, 2001, as it reentered Earth's atmosphere above the Pacific Ocean near Fiji. Though most of the station, weighing 286,600 pounds (130,000 kilograms), burned up in the atmosphere, about 1,500 fragments reached Earth's surface. Beachgoers in Nadi, Fiji, snapped photos of blazing bits of Mir debris and there were reports of sonic booms caused by heavy debris.
Weighing in at 77 tons (70,000 kilograms), the first and only solely-U.S. <a href="http://www.space.com/php/multimedia/imagegallery/igviewer.php?imgid=1108&gid=87">space station Skylab</a> launched into orbit on May 14, 1973. Its orbiting operations came to a premature end on July 11, 1979, when Skylab plummeted through the atmosphere, sending chunks of debris raining down over an area stretching from the Southeastern Indian Ocean across a sparsely populated section of Western Australia.