Tiangong 1 is coming down

The first Chinese space station has been slowly sinking ever since China publicly acknowledged that control had been lost nearly two years ago, on March 21, 2016.  It’s large enough that portions are expected to survive reentry, but where they will come down is impossible to predict more than a few weeks out from reentry.

Well, we’re now less than a month from reentry; the current prediction is April 3, give or take a week.  A year ago, all that could be said was that it would reenter somewhere under its orbital path, which rules out about a third of the planet.  (It never goes further north or south than 42.7 degrees, so anywhere beyond that is safe.)  Although it could fall anywhere in that band, the current prediction from aerospace.org is that it is most likely to fall at the extreme ends of that.

The band of greatest risk in North America include: most of Oregon, northernmost California, bits of Idaho and Utah, most of Wyoming, a bit of Colorado, a bit of South Dakota, all of Nebraska, a bit of Kansas, all of Iowa, northernmost Missouri, a bit of Wisconsin, the northern half of Illinois and Indiana and the lower peninsula of Michigan, Ohio, the peninsula of Ontario, a bit of West Virginia, Pennsylvania, most of New York, New Jersey, Connecticut, Rhode Island, Massachusetts, part of New Hampshire, and part of Vermont.

In South America, the greatest risk is in a strip of Chile and Argentina.

In Europe, the greatest risk is in Portugal, Spain, Italy, Greece, Croatia, Serbia, Bosnia & Herzegovina, Montenegro, Kosovo, Macedonia, Albania, Bulgaria, a bit of Romania, and Turkey (including the Bosporus).

In Asia, the greatest risk is in Turkey, Armenia, Azerbaijan, a tiny bit of Iran, Turkmenistan, Uzbekistan, Kyrgyzstan, Kazakhstan, Afghanistan, China (including of course the launch site in Jiuquan), a bit of Mongolia, North Korea, and Japan.

Africa is completely within the risk area, but does not touch the areas of greatest risk.

Australia’s island of Tasmania is in the southern greatest risk band, as is most of New Zealand’s North Island and part of the South Island.

The good news is that the vast majority of these bands are still over ocean, and statistically, you are a million times more likely to win the Powerball jackpot than you are to be hit by debris.  Personally, I rather hope it reenters someplace where GOES-East can see it.  The role of GOES-East is currently being filled by one of NOAA’s newest satellites, and it’s got the fastest refresh rate of any geosynchronous spacecraft (well, apart from the new GOES satellite that launched last week; that one has all the same features but isn’t yet in service).  It would be wonderful to get some useful data on the behavior of reentering spacecraft.  As LEO becomes increasingly cluttered, that knowledge becomes progressively more urgent.

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