The sky is falling. Once again.
It is expected that China’s first space station, Tiangong-1, abandoned and bred out of control, out of orbit over the weekend, and part of it is likely to survive as a result of the fierce return and accident somewhere from the earth.
Do not worry
According to experts in space debris, the chances of it falling personally on a piece of space metal are almost zero, less than a trillion.
“It’s really very, very, very small possibility,” – said Andrew Abraham, analyst, directing the monitoring and forecasting efforts of the disappearance of the space station in the Aerospace Corporation, a non-profit organization that conducts research and analysis for the United States Air Force. “Of course, I’ll worry about things like the intersection of the street is much bigger than the remains of Tingun.”
Tim Florer, a space debris analyst at the European Space Agency, said the risk is “significantly less than lightning.”
For people north of 42.7 degrees north latitude, including the inhabitants of Seattle, the United Kingdom and almost all of Russia, the possibilities are even better: exactly zero. This is because the orbit of Tingun-1 never goes so far north.
The same applies to regions south of 42.7 degrees south. Latitudes, but this part is almost completely unoccupied, with the exception of the South American islands and several scientific research stations scattered throughout Antarctica.
The European Space Agency has just updated its forecast for the disappearance of Tiangong-1, signaling its fall at any time from Friday to next Monday.
Aerospace offers a similar forecast: Sunday, more or less a couple of days.
In recent days, the forecasts have remained unchanged and uncertainty has decreased. However, it is impossible to determine where the station will go down, which is currently circling the Earth 16 times a day. The experts will not have a good idea until the last hours.
China launched Tiangong-1 – Tiangong translates as “heavenly palace” – in 2011, in fact, is a test of the concept of technology for future larger stations. It weighs approximately 19,000 pounds and consists of two modules; one of which includes bedrooms for two and other engines, life support systems and solar panels.
As a general rule, for something large, 10% to 40% of the mass will reach the surface without burning. The Chinese did not provide details of the design of the space station, which makes it difficult to calculate a more accurate estimate.
Initially, China planned to use engines to guide Tiangong-1 to splash harmlessly in the ocean. But in 2016, an obvious malfunction completed communication with the spacecraft. (The Chinese, too, did not expect this much).
Since then, Tiangong-1 has decreased and declined gradually as it advances to the upper part of the upper atmosphere. On Monday, it was at an altitude of approximately 130 miles, each day losing more than a mile, and its descent accelerates.
It is difficult to make accurate forecasts; The atmosphere adjusts and deflates depending on the particle barrier in the solar wind and how this phenomenon accelerates or slows the rate of fall. If the calculation is off for half an hour, the predicted impact site may be on the other side of the planet. Earlier this month, the solar storm seems to have moved the demolition program for several hours.
In fact, space agencies such as ESA Tiangong-1 are used as a training exercise to compare their prediction models.
The dynamics of the fall of the spacecraft can also affect time. Radar measurements show that the Tiangong-1 jumps down about once every three minutes, said Stijn Lemmens, a debris analyst E.S.A. in Darmstadt, Germany. But in this case, the fall does not seem to accelerate or prolong the remaining days of Tiangong-1.
Things of this size fall from the sky every year or so.
NASA’s satellite for Atmospheric Research, which weighed around 12,000 pounds, made an uncontrolled return similar to Earth in 2011, and it is expected that 26 large pieces, the heaviest about 330 pounds, will come to the surface. The spacecraft was in the Pacific Ocean.
Even much larger spacecraft fell, without harming people. Skylab, the world’s first space station, weighing almost 10 times more than the Tiangong-1, and when it collapsed in 1979, the pieces landed in Western Australia without incident.
When the space shuttle Columbia disintegrated during reentry in 2003, the seven astronauts on board died, but no one on earth was injured as waste with a weight of 82,000 to 85.0