The threat of dead satellites freefalling from Space seems to have become a regular event these days. A month ago, it was American satellite UARS. Last weekend, we were all waiting to see where German satellite ROSAT would end up - Turns out that it too landed, without causing any casualties.
As with UARS, the scientists still don't know the exact crash location - According to their calculations ROSAT plummeted to earth sometime after 10.15pm on October 23rd. Experts believe it ended up somewhere east of Sri Lanka in the Indian Ocean, or in the Andaman Sea off the coast of Myanmar. This, is extremely fortunate, given that the projected landing spot had been the heavily populated Chinese cities of Chongqing and Chengdu.
Though ROSAT was smaller than UARS had been, more of its pieces were expected to hit the Earth and experts were particularly concerned about its heat resistant mirror breaking into sharp pieces, as it re-entered the atmosphere. Since they have had no reports of injuries or sightings, they assume that any pieces that survived are somewhere at the bottom of either of the two bodies of water.
Satellites which are objects placed by humans for purposes ranging from military operations to Space research to weather monitoring, have a limited lifespan. Once they have served their purpose, they are either moved to a slightly higher level, dubbed 'graveyard orbit' or in some cases lower, closer to the atmosphere, to enable them to disintegrate faster. Sometimes the scientists lose all communication, in which case they are left as is, until they degrade. However, as has been the case in the last two months, some satellites do not disintegrate and instead freefall to earth. The good news is that NASA is not anticipating any more falling satellites for at least 25 years - Phew!
Resources: Washingtonpost.com, howitworksdaily.com