標題: China's Space Station Is Out Of Control And Currently Crashing Towards Earth [打印本頁] 作者: Quest 時間: 2017-10-15 05:17 標題: China's Space Station Is Out Of Control And Currently Crashing Towards Earth
When China launched its first space station in 2011, ithad great ambitions of using the craft to set up a larger space complex. Butthe Chinese space agency lost control of Tiangong-1 in September 2016, and nowexperts predict the 8.5 tonne craft will come crashing back down to Earthwithin months.
Worryingly, experts are unsure precisely when the spacestation will head towards Earth - or where the debris will land. Chineseofficials confirmed that they had lost control of the spacecraft in September2016, and have now predicted that it will come down to Earth betweenOctober 2017 and April 2018.
The station's orbit has also been steadily decaying, andin recent weeks it has started to fall faster. Speaking to the Guardian, Dr Jonathan McDowell, an astrophysicistfrom Harvard University, said: 'Now that [its] perigee is below 300km andit is in denser atmosphere, the rate of decay is getting higher.
'I expect it will come down a few months from now – late2017 or early 2018.' The Chinese space agency has been tracking the spacestation, and vowed to issue warnings if there are any potential collisionsimminent.
But not everyone is convinced by this. ThomasDorman, an amateur satellite tracker, told Space.com: 'If I am right, China will wait until thelast minute to let the world know it has a problem with their space station. 'It could be a real bad day if pieces of this came downin a populated area, but odds are it will land in the ocean or in anunpopulated area.'
Much of the spacecraft is expected to burn up in theatmosphere upon re-entry. But Dr McDowell says that some parts might still weigh upto 100kg when they crash into the Earth's surface - a size that could causesome serious damage.
And Dr McDowell added that we may only have hours ofwarning about where the spacecraft will land.
He said: 'You really can'tsteer these things.'Even a couple of days before it re-enters we probably won'tknow better than six or seven hours, plus or minus, when it's going to comedown. 'Not knowing when it's going to comedown translates as not knowing where it's going to come down.'
Tiangong-1, which means'Heavenly Palace', was launched in September 2011 with the hope of creating alarger space complex that China wants to be operational in Earth orbit around2020. The module performed a series of docking exercises, including theuncrewed Shenzhou-8 mission in 2011 and the crewed Shenzhou-10 mission in 2012.
According to the ChinaManned Space Engineering (CMSE) office, Tiangong-1 also contains Earthobservation instrumentation and space environment detectors.
In a statement in 2014,officials from CMSE, said: 'Tiangong-1 has obtained a great deal of applicationand science data, which is valuable in mineral resources investigation, oceanand forest application, hydrologic and ecological environment monitoring, landuse, urban thermal environment monitoring and emergency disaster control.'
