It is expected that an empty Chinese space station will fall back to Earth as soon as possible, and it may be possible that parts of it will survive the Iowa.
Allison Jaynes, a professor of physics and astronomy at the University of Iowa, says Tiangong I will likely come down between today and Monday, and there is a wide pathway for possible landing sites, including us.
"Most of North America, most latitudes living are on the path," says Jaynes, "but that does not mean that you're hit by any of these parts, because of course this chance is extremely low."
There are many unknowns when and where the space station will fall, but Jaynes notes that since 71
"We're not sure where exactly in its orbit it will re-enter, but the more important thing to look out for is if you're on the way to visibility, though it comes through the atmosphere, "says Jaynes. You'll probably see it even by day when you're in the right place in the world. "
Tiangong, which means" Heavenly Palace "in Chinese in 2011, is about the size of a school bus and weighs about nine and a half tons. It is 34 feet long and is filled with all sorts of equipment, large oxygen tanks, two beds and some exercise equipment, as well as two large solar panels or wings.
"Most of it will burn, they could end up with fist-sized chunks that land somewhere on the earth," says Jaynes. "This is one of the greatest things that has returned to the atmosphere, so we do not have much data on it, but by what we know, most of it burns."
So how should Iowans? Will you perform in the next few days? Should we wear helmets if we dare to go outside?
Jaynes says, "Over the next few days, you'll have many thousand times better chances of winning the lottery than being hit by anything from space."  The US Skylab space station fell in 1979. It was much larger than Tiangong – Skylab was 85 tons or about nine times heavier – and some large pieces landed in Australia. A small town attempted to punish NASA with a fine of $ 400.