Look Out Below!

Heads up, Earth!
The return of Chicken Little
The sky is falling, the sky is falling!
U.S. Spy Sat to Splat

That last one is my favorite and it's the only real headline, used by Satnews Daily. This headline fun is being brought to you by the Associated Press (AP), who are reporting that a large U.S. spy satellite has lost power and is now falling back to Earth. Government officials aren't saying much, just than the satellite can be expected to re-enter the Earth's atmosphere by late February or early March and that the appropriate government agencies are monitoring the situation. My guess is that would include the DoD, NSC, NSA, and NASA.

This particular satellite was launched by the Department of Defense, not NASA, but that doesn't preclude the space agency's involvement at this time. Both the Air Force and NASA maintain tracking stations across the globe to identify, track, and monitor all earth orbiting objects down to sizes of tens of centimeters. In fact, there are lost tools that astronauts have accidentally let go while working in space that now are in orbits of their own that are being tracked. Of course, any object in orbit without its own propulsion system will eventually lose altitude and encounter the upper atmosphere, break-up, and disintegrate. This happens to the vast majority of space debris.

However, as witnesses to Skylab, Mir, and Columbia will attest, when the object re-entering the atmosphere is above a certain size, many pieces can survive the intense heat and come out the other side still intact (to a degree). When Skylab fell back to Earth, an oxygen tank the size of a large desk landed on the coast of Australia and the U.S. was charged for littering. Mir was slightly different as it's de-orbiting was controlled by it's onboard rockets so that any pieces surviving the re-entry process would fall harmlessly in the Pacific Ocean, which they did. And most recently, the Columbia accident left sizeable debris across the southwestern United States when it began re-entry under control and lost it soon after.

According to the AP, defense and intelligence expert, John Pike, estimates this spy satellite to be around 10 tons (20,000 lbs) and the size of a small bus. That's a lot smaller than any of the three examples above, but still large enough to do some damage were it to come down in a populated place. You may remember from Geography 101 that the Earth is covered by 70% water, so the odds are in our favor. At this time though, most likely due to both the secrecy surrounding government satellites and the government's desire to perhaps destroy it instead of letting a piece of intelligence out of our hands, details of where and when are complete unknowns.

A quick scan of the web brought up some international coverage of the situation and its interesting to note the different perspectives:

CTV in Canada mention the possible fuel on board as hydrazine and raise the concern of toxic exposure to the chemical should it re-enter in a populous area. They don't allude to it, but Canada was the victim of nuclear space debris once before at the hand of a Russian satellite that crashed in the skies over the Northern Territories in 1978.

Moscow released only a tersely worded statement via Interfax-AVN, declining any alarm over the situation.

And India Daily hypes the idea that China and Russia would jump at the chance to hijack the satellite to steal our spy technology, if it were possible.

At this point though, not much to do but wait...and keep one eye on the sky.