mardi 27 mars 2018

The Chinese space station will fall from the sky like Easter eggs

CASC - Tiangong-1 Mission patch.

March 27, 2018

The end of Tiangong-1, the Chinese station out of control since the end of 2016, is near. It should hit the ground between March 29th and April 3rd.


According to legend, at Easter, eggs made of sugar or chocolate would fall bells for the delight of little gourmands.

This year, in addition to treats, it's a space station that will fall from the sky. Indeed, it has been several months since Tiangong-1, owned by the Chinese space agency, began its descent on earth. The only problem, since the end of 2016 the "Heaven Palace", its English name, is out of control.

Video above: World exlcusive higly topical radar image video of Tiangong-1 based on data recorded today! Altitude: 200,5 km perigee, Rotation speed has increased, now 2,2 °/s -> 2:23 min per one turn. Video Credit: Fraunhofer FHR.

If we mentioned southern Europe as an impact point, it seems risky to say exactly where the machine will land. However, we know more or less when. Last Thursday, the National Center for Space Studies (Cnes, France) and the European Space Agency (Esa) raised a window between March 29 and April 3. Probably March 31, according to experts. Precisions should be further refined in the coming weeks, says the daily Sud Ouest.

Not enough to panic

Tiangong-1 radar images

As for the location of the impact, the uncertainty will be up to the last 24 hours preceding the entry into the atmosphere of the space station. "The inclination of the orbit of the Chinese station is about 42.8 degrees, explains South West Stéphane Christy, expert at the National Center for Space Studies of Toulouse. This means that if we project this orbit on a planisphere, the land area on which the object will fall is a band between latitudes - 42.8 ° and + 42.8 °.

Tiangong-1 radar images

Although Tiangong-1 is a big cylinder of about 10 meters long for 8.5 tons, there is nothing to worry about. Citing a NASA report from 2011, the French newspaper recalls in particular that the probability that space debris affects a human being to about 1 in 3,200.

Related articles:

Chinese space station risks crashing in France

Uncontrolled crash on Earth of a Chinese space station

Related link:

Fraunhofer Institute for High Frequency Physics and Radar Techniques FHR:

Images , Video (mentioned), Text, Credits: DRI/CASC/Fraunhofer FHR/ Aerospace/Roland Berga.


1 commentaire:

  1. Any credible hazard doesn't involve getting bonked on the head -- it relates to hazardous materials on board, a feature that the Chinese have been adamantine in refusing to disclose. Frozen hydrazine is the most likely threat to area contamination, as with the USA-193 spy satellite ten years ago where probability of human casualties was estimated to be as high as one in forty [hence the one-time decision to smash it to pieces just before atmospheric entry]. Propellant tanks from the doomed Columbia shuttle that disintegrated over East Texas ere also considered particularly dangerous. That was the issue also with two Russian Mars probes that failed in parking orbit in the last twenty years -- they fell randomly and both arguably scattered debris [including chemical-stuffed fuel tanks] across South America, despite official Moscow claims they had actually fallen into the Pacific. The USSR's hundred-ton Polyus prototype laser battle station did fall in the eastern Pacific thirty years ago, when its orbital burn failed. I'm also surprised that Kosmos-954 and its Canadian-tundra-contaminating radioactive fuel wasn't mentioned [one Russian Mars probe also carried plutonium batteries which landed in the Andes, and since they were heat-shielded to land on Mars their intact survival to the surface was almost certain -- as was the Apollo-13 ALSEP nuclear battery intended for lunar surface deployment]. These are the random satellite fall issues that carry the most hazard, but since China is stonewalling the issue of such on-board materials, the theme seems neglected.