Scientists have also underlined the space station will most likely disintegrate upon reentering the atmosphere, spectacularly burning up on its fiery descent.
Some at NASA wanted Skylab to remain aloft longer.
It is now orbiting at an average height of about 216.2 kilometres, but experts are still unclear about the exact location of re-entry. In 1979, Time magazine wrote of the upcoming event: "Thus will be observed, after a series of miscalculations, the tenth anniversary of man's proudest achievement in space, the walk on the moon".
The fact that Beijing also lies in Tiangong-1's "hit belt" has prompted some space aficionados to wish the "rogue" space lab, now running wild at an average height of 216.2 kilometers, heads straight back to the Chinese capital, rather than anywhere else, on its "homecoming trip".
Tiangong-1's potential re-entry areas. "These include the natural rotation speed, the manner in which Tiangong-1 breaks up into several parts, the time of the break-up and the actual weather conditions in space".
In 1979, the 77-tonne US space station Skylab fell toward Earth, with some pieces, both large and small, reaching the ground.
Thankfully the probability of impact is low - only about 0.2 percent.
Since June 25, 2013, Tiangong-1 has simply been orbiting the planet on its own, with no more visits from any spacecraft, crewed or otherwise, and as of March of 2016, China hasn't even been in contact with the station, as it had "ceased functioning".
The space station - which launched to orbit in 2011 - will circle the Earth dozens of times over the course of the weekend, before the station is expected to re-enter.
A United Nations agreement means any part of Tiangong-1 remains the property of China.
However, the satellite is not expected to survive re-entry into the Earth's atmosphere and is expected to fall out of orbit in the beginning of April.
As with all large satellites and spacecraft, the Chinese spacelab had been slated for a "controlled reentry" that would have seen it fall somewhere in the Pacific Ocean, far from human habitation.
Scientists are nervously watching the 19,000-pound Tiangong 1, which will likely make its way back to Earth around April 1, according to the Aerospace Corporation that is closely monitoring the situation.