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[Thursday morning UARS update: The Aerospace Corporation UARS map now shows UARS most likely crashing off the western coast of South America once again — but further to the north than the previous prediction of a crash in the eastern Pacific. I’m also finally getting a handle on how to convert UTC to EDT. EDT is 4 hours behind UTC. This means the latest prediction of a crash at about 2200 UTC translates to about 6 p.m. East Coast USA time, conveniently in time for the first edition, though it could mess up my very important evening plans! FYI, the satellite is now coming in a bit slower than anticipated.] [Oh yeah, speaking of plan: I’ll be at the National Book Festival this weekend if anyone wants to come by and hear me yammer about the BP oil spill.]

[Wednesday night UARS update: NASA says that North America will be spared the shock and horror of charred metal raining from the sky like the biblical plague of satellites (I need to check the exact reference but believe its in Exodus). NASA says that as of early this afternoon, UARS was 120 miles up — barely in space if you ask me. Gotta be dragging at that altitude. NASA says: “Re-entry is expected sometime during the afternoon of Sept. 23, Eastern Daylight Time. The satellite will not be passing over North America during that time period.”

The Aerospace Corporation UARS map shows it coming down in the Western Pacific at about 2 p.m. [[Correction: 4 p.m.]] EDT. I just hope it doesn’t come down on both sides of the International Date Line because then we won’t know what day it crashed. This has been confusing enough.]

This just in: Washington will be spared when the NASA satellite UARS crashes to Earth. So will Manhattan. Indeed, the entire East Coast of the U.S. looks safe as I examine the projected crash map.

This isn’t class warfare, it’s just physics.

Although we don’t know where the dadgum thing is going to crash, and it could still hit any continent except Antarctica, there are very well-defined orbital tracks that show where it will be going in the final few days before the expected Friday-ish re-entry, spectacular fireballing and debris-spewing.

One trajectory, for example, shows it passing over Texas and close to Chicago. Europe is very much in the line of fire, with multiple trajectories that pass over that land mass.

The orbit is at an inclination of 57 degrees to the Equator, which means that UARS passes over points ranging from 57 degrees north latitude to 57 degrees south latitude. But it won’t literally pass over every spot on the planet between those latitudes. It traces a path that can now be constrained a great deal, and if you look at this map from the Aerospace Corporation you’ll see that it’s not going to hit the U.S. Capitol and disrupt the highly productive political process that is going to solve the fiscal conundrum and put Americans back to work.

The Aerospace Corporation map uses Air Force tracking data and feeds it through a software program to come up with an estimate. This afternoon the best estimate showed the tumbling satellite entering the atmosphere just west of South America at 4:36 p.m. EDT, and likely spraying debris across the Andes and perhaps the Amazon basin. But yesterday the map showed it crashing in the South Atlantic near South Africa, and my sources say that the next update (which may occur as I’m typing) will show a different location yet again.

This map shows the track of the satellite before the projected re-entry point (blue lines) and after the projected entry point (yellow lines). You’ll notice that the margin of error literally goes around the world several times.

In fact, just a 30-minute difference in the re-entry translates into the satellite hitting Europe instead of the western coast of South America.

The actual margin of error is even greater than depicted here – about plus-or-minus-20 hours as of Tuesday afternoon, while the map shows only plus-or-minus-6 hours. But I’m told by the AC people that they don’t have any track that takes it directly over the East Coast.

Remember: There’s a 1-in-3200 chance that it will strike a human being somewhere on the planet, according to NASA. That’s not the odds that it will strike YOU. Just some human. And there are 7 billion humans. See more from Jason Samenow.

Stay tuned to your UARS-stalking A-blog.