穆赫兰道

'NASA ready to take whatever Universe throws at us'_我的网站

工商银行

一 | Washington, Oct 12 (UNI) American space agency NASA says its recent attempt to deflect the path of an asteroid was successful, after its Dart probe struck an asteroid head-on.
Scientists have now confirmed the orbit of a 160m-wide space rock known as Dimorphos was altered when the Dart probe struck it head on last month.
Researchers came to the conclusion after making measurements using a range of space and Earth-based telescopes.
The mission was conceived to test a potential strategy to defend the Earth against threatening objects.
Dart's achievement proves such an idea would work, provided it was initiated early enough and the target wasn't overly massive.
"This mission shows that Nasa is trying to be ready for whatever the Universe throws at us," said agency administrator Bill Nelson.
"I believe that Nasa has proven that we are serious as a defender of the planet," he told reporters.
The space agency released a raft of data on Tuesday to support its assessment, including new pictures from the Hubble Space Telescope and from a small Italian spacecraft that stood off from the impact by about 50km (30 miles).
The Double Asteroid Redirection Test (Dart) took place some 11 million km (7 million miles) from Earth.
It saw the refrigerator-sized Nasa satellite drive straight into Dimorphos at 22,000km/h (14,000mph), destroying itself in the process.
The space rock orbits a much larger (780m wide; 2,550ft) object called Didymos. Before impact, the time taken for Dimorphos to make one circuit of its sibling was 11 hours and 55 minutes.
The telescope evidence now indicates this orbital period has been reduced to 11 hours and 23 minutes - a change of 32 minutes. This corresponds to Dimorphos moving closer into to Didymos by "tens of metres".
Nasa had defined a minimum successful period change of Dimorphos of 73 seconds or more. The results released on Tuesday show Dart surpassed this benchmark by more than 25 times.
"This is a 4 percent change in the orbital period of Dimorphos around Didymos. Dart just gave it a small nudge. But if you wanted to do this in the future, you'd want to do it years in advance," commented Nancy Chabot from the Johns Hopkins University Applied Physics Laboratory, which led the mission for Nasa.
"Warning time is really key here in order to enable this sort of asteroid deflection to be used in the future as part of a much larger planetary defence strategy."
Nasa's Dart programme scientist, Tom Statler, also had a word of caution about drawing too many conclusions from the experiment.
Asteroids came in many different guises, he said. Their compositions and constructions were diverse - something that was being emphasised every time a mission visited a new object.
"We should not be too eager to say one test on one asteroid tells us exactly how every other asteroid would behave in a similar situation," he stressed.
"But what we can do is use this test as an anchor point for our physics calculations in our simulations that tell us how different kinds of impacts in different situations should behave."
Four years from now, the European Space Agency (Esa) will have three spacecraft - collectively known as the Hera mission - at Didymos and Dimorphos to make follow-up studies.
UNI ING。 8月25日消息，树莓派发布了一份免费的官方指南，手把手教大家用现成组件在防护箱里组装一台便携式的赛博朋克工作站。

二 | 这种自制便携电脑在创客圈被称为赛博甲板（Cyberdeck），近年来越来越火。它的形态五花八门，有人用公文包、木盒装，还有人塞进老式口袋电脑甚至锡罐里，树莓派自己选了一个鹈鹕风格的坚固防护箱，防风雨、耐造还好带。官方示例的配置包括一台树莓派5、一块7英寸触摸屏、蓝牙键盘、扬声器、USB音频系统、电池，以及128GB闪存盘和一颗RTC电池（用于关机后保持时钟运行）。按照官方说法，任何一台赛博甲板都由四部分组成：电脑本身、外围设备、电源系统和机箱。树莓派建议用单板计算机方案，功耗比传统PC平台低得多，存储可以从SD卡一路扩展到M.2 NVMe固态硬盘。