Picture
Following on from a previous post regarding the descent of the Upper Atmosphere Research Satellite (UARS), it would appear that the bus sized piece of space junk safely re-entered the Earth’s atmosphere early on Saturday morning 24th September 2011.

By a stroke of luck the vessel plunged to earth somewhere over the southern Pacific Ocean about as far from large land masses as you can get, reducing any possibilities of damage or injury being caused by the 26 parts that would survive the fiery heat of re-entry.

After the launch of this satellite in 1991, NASA and other space agencies agreed to adopt new procedures in an effort to reduce space junk and lessen the possibilities of future satellites causing problems when falling back to Earth.

However, in the immediate future the German satellite ROSAT, launched in 1990 and weighing in at 2.5 tonnes is expected to fall back to Earth in late October or early November this year. Some 30 pieces of debris are expected to survive re-entry, potentially including sharp mirror shards, so we should all continue to keep looking warily to the skies for now! 



 
 
Picture
A redundant six-tonne NASA satellite is expected to re-enter the Earth’s atmosphere with the next few hours, potentially scattering debris over a 500km wide area of the planet’s surface.

Whilst the majority of the bus sized Upper Atmosphere Research Satellite (UARS) will burn up upon re-entry into our atmosphere, NASA has indicated that about 26 parts will survive the intense heat and will fall to Earth: including 4 titanium fuel tanks, 3 batteries, 4 steel flywheel rims and an aluminium structure that on its own will weigh 158kg.

Although NASA is tracking the orbit of the falling satellite, the final destination of these objects won’t be known until minutes beforehand due to continuous changes in the atmosphere caused by the Sun.

Target zone is anywhere between 57 degrees latitude north and 57 degrees latitude south, i.e if you live further north than Quebec or further south than Argentina you should not be at risk.

Though you may cast an occasional look to the skies over the next day, I wouldn’t worry too much as you would have to be incredibly unlucky to be struck by some of the falling debris. NASA calculates that there is a 1 in 3,200 chance that a piece will hit a person somewhere on the planet, whilst you own personal risk of you specifically being struck is 1 in 21 trillion – you are far more likely to win this week’s lottery!