Lumps of a US satellite are due to hit somewhere in Nothern Hemisphere. Chance of someone being hit are estimated as 1/3200. The satellite was launched to measure upper atmosphere climate, like the weather balloons used by UK scientists who discoved the Ozone hole. Don’t worry the satellite won’t hit the US, NASA say. They can’t say were it will land, but they can make sure it isn’t USA. It is expected to make reentry on friday night or saturday morning.
The satellite is the biggest “mission to earth” satellite ever launched, or planned to be launched.
Most of the six tonne satellite is aluminium and expected to vaporise on re-entry, but about 1 tonne of the satellite is made from steel and titanium alloys which are expected to survive.
Nasa mission page:
http://www.nasa.gov/mission_pages/uars/index.html
bainite 
In the end this satellite reentered in the indian ocean off the coast of africa, I don’t remember hearing about it on the news.