Let the chips fall (but not on us)
The Upper Atmosphere Research Satellite in the grasp of the remote manipulator system during deployment, from the space shuttle in September 1991. Credit: AP
What happens when an Upper Atmosphere Research Satellite the size of a bus doesn't stay in the upper atmosphere?
It comes crashing to Earth, as one is about to do tomorrow. NASA says it's pretty sure about the date and has narrowed the landing area to, well, somewhere on Earth between the North and South poles.
NASA launched the 13,000- pound satellite in 1991 to learn more about the ozone layer, stratospheric winds and other climate-related stuff. And the satellite produced. It was only designed to last 18 months, but upgrades extended its useful life until 2005.
The bad news is that at least 26 large pieces of the device are expected to survive a fiery re-entry. The odds any person will be struck are one in 3,200, but since there are nearly 7 billion people, the odds you will get hit exceed one in 2 trillion. So there's no need to buy a helmet -- and frankly, an umbrella would give you as much protection against chunks of flaming metal descending from 375 miles up. The largest piece might weigh 300 pounds.
But let's look on the bright side. The satellite's descent should produce one heck of a light show, although it may not be visible from everywhere. And perhaps we should welcome a relatively harmless reminder of the tiny chance that catastrophe can fall on anyone at any moment. It's what the ancients called a memento mori, and can only help us savor the sweetness of daily life all the more.
