周一至周五: 8:30-17:30



首页 > 新闻资讯

日本研发出世界首颗木制卫星 使用后不会造成太空污染



日本研发出世界首颗木制卫星 使用后不会造成太空污染(图1)
The wooden LignoSat satellite that will burn into ash when it re-enters the atmosphere [artist’s impression]. Photograph: Kyoto University


Japanese scientists have created one of the world’s most unusual spacecraft – a tiny satellite that is made of timber.



The LignoSat probe has been built of magnolia wood, which, in experiments carried out on the International Space Station (ISS), was found to be particularly stable and resistant to cracking. Now plans are being finalised for it to be launched on a US rocket this summer.



The timber satellite has been built by researchers at Kyoto University and the logging company Sumitomo Forestry in order to test the idea of using biodegradable materials such as wood to see if they can act as environmentally friendly alternatives to the metals from which all satellites are currently constructed.



"All the satellites which re-enter the Earth’s atmosphere burn and create tiny alumina particles, which will float in the upper atmosphere for many years,” Takao Doi, a Japanese astronaut and aerospace engineer with Kyoto University, warned recently. “Eventually, it will affect the environment of the Earth.”



To tackle the problem, Kyoto researchers set up a project to evaluate types of wood to determine how well they could withstand the rigours of space launch and lengthy flights in orbit round the Earth. The first tests were carried out in laboratories that recreated conditions in space, and wood samples were found to have suffered no measurable changes in mass or signs of decomposition or damage.



"Wood’s ability to withstand these conditions astounded us,” said Koji Murata, head of the project.



After these tests, samples were sent to the ISS, where they were subjected to exposure trials for almost a year before being brought back to Earth. Again they showed little signs of damage, a phenomenon that Murata attributed to the fact that there is no oxygen in space which could cause wood to burn, and no living creatures to cause it to rot.



Several types of wood were tested, including Japanese cherry, with wood from magnolia trees proving to be the most robust. This has now been used to build Kyoto’s wooden satellite, said Murata.



Murata added that a final decision had still to be made on the launch vehicle, with choices now narrowed down to a flight this summer on an Orbital Sciences Cygnus supply ship to the ISS or a similar SpaceX Dragon mission slightly later in the year. It is expected that the probe – which is the size of a coffee mug –will operate in space for at least six months before it is allowed to enter the upper atmosphere.



If the LignoSat performs well ­during its operation in orbit, then the door could be opened for the use of wood as a construction material for more satellites. It is estimated that more than 2,000 spacecraft are likely to be launched annually in coming years, and the aluminium that they are likely to deposit in the upper atmosphere as they burn up on re-entry could soon pose major environmental problems.



Recent research carried out by scientists at the University of British Columbia, Canada, revealed that aluminium from re-entering satellites could cause serious depletion of the ozone layer which protects the Earth from the sun’s ultraviolet radiation and could also affect the amount of sunlight that travels through the atmosphere and reaches the ground.



However, this should not be a problem with satellites built of wood, like LignoSat, which, when it burns up as it re-enters the atmosphere after completing its mission, will produce only a fine spray of ­biodegradable ash.





图文来源:新华网、Variety、索尼影业、央视网 、每日经济新闻、 极目新闻、 红星新闻、 工人日报、福克斯新闻网、新浪、观察者网、卫报、BBC、sciencealert、 Pixar、Paramount Pictures、Sony、Warner Bros、Lucasfilm、Twitter、BBC、新华社、雅虎新闻、Oddity Central、纽约邮报、CBS新闻、美国有线电视新闻网、Unsplash、Pexels、中国日报等综合整理,新闻资讯均转载自其它媒体,目的在于传播更多信息,其他媒体如需转载,请与稿件来源方联系,如产生任何问题与本网无关;本网所发布的内容,图片,音乐,电影等片段,版权归原作者所有,仅供学习与研究,如果侵权,请提供版权证明,以便尽快删除。

点击次数:   更新时间:2024-02-20  【打印此页】  【关闭
3024596866 / 2855328232