日韩精品久久一区二区三区_亚洲色图p_亚洲综合在线最大成人_国产中出在线观看_日韩免费_亚洲综合在线一区

Global EditionASIA 中文雙語Fran?ais
China
Home / China / Innovation

Tiangong-1 unlikely to cause damage to ground

Xinhua | Updated: 2018-03-29 18:44
Share
Share - WeChat

BEIJING - China's first space lab Tiangong-1 will mostly be burnt up in the atmosphere and it's highly unlikely to cause any damage on the ground, according to an article published by China Manned Space Engineering Office (CMSEO) recently.

"There is no need for people to worry about its re-entry into the atmosphere. It won't crash to the Earth fiercely, as in sci-fi movie scenarios, but will look more like a shower of meteors," the article said.

During a meteor shower, about 1,000 to 20,000 meteorites fall to Earth per hour, and the probability of a person being hit by a meteorite of more than 200 grams is one-700 millionth, it said.

The CMSEO announced earlier that Tiangong-1 has seen its orbit decay since it ended its data service on March 16, 2016, and will re-enter the atmosphere between March 31 and April 4.

Tiangong-1, with a weight of about eight tons, is much smaller the 80-ton Skylab and 140-ton Mir, and is unlikely to affect aviation activities or cause damage on the ground, the article said.

The re-entry process is usually divided into three phases. During the first phase, the atmospheric drag will rip solar arrays, antennas, and other external parts off a spacecraft at an altitude of about 100 kilometers.

As it continues to fall, the main structure of the spacecraft will get burnt or exploded with increasing heat and friction. It normally disintegrates at an altitude of about 80 kilometers.

The fragments will keep burning and most of them will get dissipated in air. Only a small amount of debris will reach the ground, and will float down at a very slow speed due to their small mass.

The surviving fragments will most likely fall into the oceans, which cover more than 70 percent of the Earth's surface, instead of hitting densely-populated areas, the article said.

More than 15,000 tons of spacecraft debris have fallen to Earth since the 1960s, but no people have ever been hurt by it, the article said.

Lisa Ruth Rand from the University of Wisconsin-Madison also believes that it's unlikely that anyone will be hit by the debris of Tiangong-1.

"When an object like Tiangong-1 falls back to Earth, the atmosphere subjects it to friction and pressure. This breaks apart larger objects into fragments, vaporizing and dissipating quite a bit of material in the process," Rand told Xinhua in an email.

Tiangong-1 has docked with Shenzhou-8, Shenzhou-9, and Shenzhou-10 spacecraft and undertaken a series of tasks, making important contributions to China's manned space cause, the article said.

Top
BACK TO THE TOP
English
Copyright 1995 - . All rights reserved. The content (including but not limited to text, photo, multimedia information, etc) published in this site belongs to China Daily Information Co (CDIC). Without written authorization from CDIC, such content shall not be republished or used in any form. Note: Browsers with 1024*768 or higher resolution are suggested for this site.
License for publishing multimedia online 0108263

Registration Number: 130349
FOLLOW US
 
主站蜘蛛池模板: 毛片免费视频 | 国产成人18黄网站免费 | 三级a做爰大乳在线观看 | 日韩精品毛片 | 日本黄色大片免费 | 久久视频在线免费观看 | 欧美日韩第二页 | 草草草影院 | 波多野结衣全部系列在线观看 | 亚洲精品成人a | 国产成人综合在线 | 欧美激情久久久 | 亚州AV无码乱码色情 | 69av在线视频 | 色视频网站在线观看 | 天堂一区二区三区四区 | 日本三级网址 | 日本免费a视频 | 成人不卡在线 | 视频一区二区在线观看 | 日韩中文一区二区三区 | 国产福利专区精品视频 | 国产在线看片 | 干片网 | 欧美最新一区二区三区四区 | 欧美区在线| 免费观看一级特黄欧美大片 | 爽爽影院在线看 | 亚洲香蕉久久一区二区三区四区 | 亚洲国产成人在线 | 欧美综合视频在线 | 很黄很色又爽很黄很色又爽 | 黑人xxx视频 | 国产探花在线精品一区二区 | 亚洲日本在线观看视频 | 欧美人xx | 国产午夜精品视频免费不卡69堂 | 国产日韩欧美精品 | 亚洲日韩欧美视频 | 奇米影视在线 | 欧美激情精品久久久久久久 |