Experts say it is nearly impossible to determine the exact time and location of the crash.
The 9.4-ton spacecraft potentially contains large amounts of hydrazine, a toxic, flammable chemical that is very dangerous to humans.
But debris from Tiangong-1 is extremely unlikely to hit people.
The 9.4-ton station is now on the verge of breaking up in the atmosphere, with the debris crashing to Earth this weekend.
The colorless and volatile liquid, used in Tiangong-1's engine for fuel, is dangerous to humans. Emitting an ammonia-like odor, hydrazine can poison the blood, kidneys, lungs, and the central nervous system. It can also severely burn skin and damage the eyes, nose, and mouth, among other things.
The Aerospace Corporation’s Center for Orbital and Reentry Debris Studies (CORDS) warns: "Potentially, there may be a highly toxic and corrosive substance called hydrazine on board the spacecraft that could survive reentry. For your safety, do not touch any debris you may find on the ground nor inhale vapors it may emit."
As BI's Dave Mosher notes, it's nearly impossible to determine exactly where and when the satellite laboratory will land on Earth. On March 26, the European Space Agency released this map of where the space station might crash (highlighted in green):
ESAThe chances of Tiangong-1's re-entry are slightly higher in New Zealand, Tasmania, the northern states of the US, northern China, the Middle East, central Italy, northern Spain, and parts of South America and southern Africa.
The degree to which the Earth's atmosphere will burn up the craft is also still unclear, but scientists predict that some pieces will survive. The chunks could sprinkle over a long, thin area of up to 1,000 miles.
The best-case scenario would be that Tiangong-1 lands in the sea, which is statistically more likely than it hitting land, since oceans take up 70% of Earth. If it crashes into water, there would be less of a chance of a curious human hunting for the debris and coming into contact with hydrazine.