It'll rain debris. It is not possible to say wher this will happen on Good Friday or Easter Monday. It is difficult to predict wher and where exactly metal parts will be hit on ground. In any case, over holidays China's former pride, disused space station Tiangong 1, will crash. And this is rar uncontrollable, because steering vehicle from size of an omnibus is no longer possible. Two years ago, engineers lost contact with eight and-ton spacecraft.
The soothing message: bulk of material will burn out when re-entering Earth's atmosphere. Only 20 to 40 percent will be over this phase, estimates European Space Agency ESA. The parts, which occasionally find ir way to Earth, most likely land somewhere between 43 degrees south and 43 degrees north (see map). And this is an immense area. Only one third of land areas of earth are located in a zone where probability of a scrap of Tiangong 1 is lower than zero. At same time, however, in zone where debris could fall, statistical chance that a human being can get such a man-made meteorite is extremely low. So far, only one case is known in which a woman in Oklahoma in 1997 was hit by a piece of space debris, but luckily not hurt.
Where Tiangong 1 could enter atmosphereParts of Chinese space station could plunge into Earth's surface within a very broad region. What is certain is that this will be between 42.7 degrees North or south latitude. At edge of this region, debris is more likely, European Space Agency ESA estimates.
Marked in grey: a typical circular path on which Tiangong 1 can move within 24 hours. Source: Esa time online changeable space WearThe fact that crash of China's space location is so difficult to predict in detail lies above all in changing wear in space: "We simply do not know how high atmosphere in areas between 100 and 200 kilometers is behaving. It can inflate from one day to or and be twice as dense – depending on solar activity, "says Holger Krag, head of Space Debris office at ESA. To this day, it is impossible to understand how sun behaves – and it has an enormous influence on atmosphere. "A second uncertainty is dynamics of station. Staggers you? Does it fly ahead with largest or smallest surface? All this makes an accurate prediction impossible. " For ESA, Krag, as part of an international Committee for Coordination of all matters relating to space debris (IADC), is working to coordinate monitoring of crash with twelve or organizations when it is ready.
Engineers are already considering end of construction of every space object: large aluminium parts, as y were also installed in Tiangong 1, will burn. Only parts of fuel tanks or in propulsion systems must withstand high heat during operating time and are refore made of titanium or stainless steel. Such parts probably also withstand re-entry of Tiangong 1 and could rain down on earth in small parts. But Krag sees no great danger in this: "The parts fall in a very large area with very little risk of injuring someone. They usually land along a distance of up to 1,200 kilometers. " During his career he has already taken care of some cases like crash of Tiangong 1. Even though rarely reported in public, satellites and space stations – or or things that man has shot into space over past few decades – often come back to Earth.
Date Of Update: 28 March 2018, 12:03
