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中國太空計畫 – 開欄文
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2025/03/02 00:59 瀏覽206 ｜回應5｜推薦1 |
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我在《國際現勢：2025》一文中說道：「我相信基因、太空、以及核融合這三方面研究，是中國未來上位龍頭老大的基礎」。太空研究之所以重要，在於它不只是科學研究和技術層級的指標，它更具有在戰爭上「決勝於千里之外」的實際應用。
由於本部落格是一個綜合型的網誌，我也只是玩票性的經營，再加上近年來身體又三不五時的出出小狀況；種種因素造成我沒有給予這方面資訊應該有的關注。好在「亡羊補牢，未為遲也」；現在加開此欄，未必會增加我注意的程度，至少能把相關訊息集中在一處，便於搜尋和參考。
本文於 2025/03/02 01:01 修改第 1 次
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中國間諜衛星能辨識人臉 ---- Alan Bradley
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2025/03/13 16:43 推薦1 |
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China creates powerful spy satellite capable of seeing facial details from low orbit
Alan Bradley, 03/12/25
New laser-based imaging technology is reportedly capable of capturing millimeter resolution from over 60 miles away.
Scientists in China have created a satellite with laser-imaging technology powerful enough to capture human facial details from more than 60 miles (100 kilometers) away.
This breakthrough represents a performance increase of 100 times or more compared to leading spy cameras and traditional telescopes, according to a report on the new technology in the South China Morning Post.
Amongst a broad gamut of potential applications, the technology could allow operators to surveil foreign satellites to a previously impossible level of detail. The researchers at China’s Academy of Sciences’ Aerospace Information Research Institute outlined their findings in a new study published in the Chinese Journal of Lasers (Issue 52, Volume 3).
PLAY SOUND 請至原網頁觀看視頻
According to the South China Morning Post, the scientists conducted a test across Qinghai Lake in the northwest of the country with a new system based on synthetic aperture lidar (SAL), a type of laser radar capable of constructing two-dimensional or three-dimensional images.
How this new powerful spy satellite works
SAL relies on the motion of an object (like a satellite) to provide finer resolution images than other, beam-scanning radar imagery systems. Previous SAR systems have relied on microwave radiation, which has longer wavelengths, which results in lower resolution images.
However, this new system operates at optical wavelengths, which have much shorter wavelengths than microwaves and produce clearer images (though microwaves are better for penetrating into materials, because their longer wavelengths aren’t scattered or absorbed as easily).
During the test, which targeted arrays of reflective prisms placed 63.3 miles (101.8 km) away from the lidar system, the device detected details as small as 0.07 inches (1.7 millimeters) and measured distances to within 0.61 inches (15.6 mm).
This is a huge leap forward from previous milestones, like a 2011 test conducted by defense firm Lockheed Martin that was able to achieve an azimuth resolution of 0.79 inches (2 centimeters) from only 1 mile (1.6 km) away, or a Chinese test where scientists achieved a then-best 1.97 inch (5 cm) resolution at a distance of 4.3 miles (6.9 km).
To achieve this latest breakthrough, the Chinese team split the laser-beam driving the lidar system across a 4x4 micro-lens array, which in turn expanded the system’s optical aperture — the opening that controls the amount of light entering a camera system — from 0.68 to 2.71 inches (17.2 mm to 68.8 mm). In this way, researchers could bypass the tradeoff of field of vision versus size of aperture, which has historically restricted such camera systems.
It’s important to note that testing took place during near perfect weather and atmospheric conditions with steady wind and limited cloud cover. Inclement weather or other impairments to visibility could significantly impact the system’s precision and reliability.
Alan Bradley is a freelance tech and entertainment journalist who specializes in computers, laptops, and video games. He's previously written for sites like PC Gamer, GamesRadar, and Rolling Stone. If you need advice on tech, or help finding the best tech deals, Alan is your man.
Related:
* NASA and Japan launch world's 1st wooden satellite into orbit
* China ready to launch 1st satellite in constellation that will challenge Elon Musk's Starlink
* China’s secretive new 'Thousands Sails' satellites are an astronomer's nightmare, 1st observations reveal
* Haunting photo of Earth and moon snapped by China's experimental lunar satellites
本文於 2025/03/13 16:44 修改第 1 次
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中國規畫建造太空太陽能站 -- Emma Frederickson
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2025/03/13 10:14 推薦1 |
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China Is Building a Solar Station in Space That Could Generate Practically Endless Power
It’s coming to a cosmos near you in 25 years!
Emma Frederickson, 03/12/25
* China is currently planning to build a gigantic solar power station in space.
* To get parts of the array out of our atmosphere, scientists are working on a reusable heavy lift rocket called the Long March-9.
* The solar array project is just one small part of China’s larger space mission.
The Three Gorges Dam—located on the Yangtze River in China—is the largest hydroelectric dam in the world. Though there is discourse over whether the dam has negative ecological effects, it is an impressive hydropower project, with over 20 times the energy-generating capacity of the Hoover Dam. Now, China wants to build another revolutionary energy source: a solar array in space.
“It is as significant as moving the Three Gorges Dam to a geostationary orbit 36,000km (22,370 miles) above the Earth,” Long Lehao, a rocket scientist and member of the Chinese Academy of Engineering (CAE), said in a lecture reported by the South China Morning Post. “This is an incredible project to look forward to.”
Space-based solar power (SBSP) stations work by using a system of mirrors to concentrate sunlight onto panels, which then generate electricity. The electricity is then converted to microwave radiation and beamed to a fixed antenna on Earth.
SBSP panels are more reliable than the solar panels on your roof because they aren’t affected by seasonal weather or nights. They can generate much more electricity than terrestrial panels, as sunlight is exponentially more intense in space than on Earth’s surface. A recent NASA study even predicted that one model of space-based solar power could generate power for a full 99% of the year.
As Long said in his lecture: “The energy collected in one year would be equivalent to the total amount of oil that can be extracted from the Earth.”
Sounds like the perfect solution to our non-renewable energy crisis, right? Well, there are a few drawbacks holding space companies back—namely, the transparent size of the project.
The solar array is predicted to be a kilometer wide once fully assembled. According to the South China Morning Post, many are calling space-based solar power stations the “Manhattan Project” of the energy world. And yet, China seems set on succeeding in this endeavor.
The European Space Agency explains that it took dozens of launches to construct the International Space Station in low-orbit, and would likely take many more to assemble a SBSP station (though, the cost of launches worldwide continues to decline).
To get their array into space, Long and his team are working on developing the Long March-9 (or CZ-9)—a reusable heavy-lift rocket with a lifting capacity of at least 150 tons. That’s like lifting a full-grown blue whale into space.
The solar array isn’t the only plan China has for space research—it also plans to reach the Moon and build an International Lunar Research station in partnership with Russia by 2035. Japan is also on track to beam space-based solar power to Earth in the next year. SBSP stations, it seems, might just be the next challenge in the space race.
本文於 2025/03/13 10:15 修改第 1 次
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中國研發隱身飛彈 - H. Baker
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2025/03/03 09:39 推薦1 |
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本欄以上各篇報導外，請參看這篇報導(2025/02/21)。
Chinese scientists reveal plans for near-invisible stealth missiles that could 'redefine modern warfare'
Harry Baker, 02/26/25
Chinese scientists claim to have found a new way of injecting helium into rocket engines, which could be used to make missiles that are much harder to detect or intercept. The new technology was allegedly inspired by the faulty spacecraft that "stranded" NASA astronauts on the ISS last year.
Chinese scientists say they have made a big breakthrough in rocket propulsion technology that could potentially allow them to build next-generation stealth missiles capable of changing speed in midair and evading detection by early warning systems.
However, at this stage, the technology has not been tested. Instead, the new findings were acquired using computer models, according to Interesting Engineering.
The reported advancement was allegedly inspired by faults in the Boeing spacecraft that "stranded" a pair of NASA astronauts on the International Space Station (ISS) last year, according to the South China Morning Post. "In an ironic twist of cosmic problem-solving, Chinese researchers have transformed a lingering NASA headache into a revolutionary propulsion breakthrough that could redefine modern warfare and space travel," the outlet reported.
PLAY SOUND 請至原網頁觀看視頻
In June 2024, astronauts Butch Wilmore and Suni Williams became trapped on the ISS after the Boeing Starliner capsule they arrived on experienced multiple issues and was later returned to Earth without any passengers. This turned what was supposed to be a roughly week-long space trip into an ongoing, 10-month mission that is expected to finally wrap up in mid-March when the astronaut pair is scheduled to return home.
The main issue with the Starliner capsule was that it was leaking helium gas (in multiple places), which is used to pressurize liquid-fuel rockets by forcing liquid fuel into the reaction chamber. This means it must be stored independently and forced through valves when it's needed, which makes it susceptible to leaking. In the past, this issue has also caused problems for other spacecraft, including India's Chandrayaan-2 and the European Space Agency's Ariane 5, according to Reuters.
Boeing's Starliner capsule experienced multiple helium leaks after transporting NASA astronauts Butch Wilmore and Sunni Williams to the ISS. (Image credit: ESA/NASA-S.Cristoforetti) 請至原網頁觀看照片
In a study published Feb. 10 in the Chinese journal Acta Aeronautica et Astronautica Sinica, researchers report that they've designed a rocket that directly mixes helium gas with the fuel within a firing engine by injecting it into the chamber via microscopic pores. This similarly pressurizes the fuel and allows for a more efficient reaction while reducing the chances of a leak. Another major difference is that this can be done with a mix of solid and gaseous fuel instead of a liquid propellant, like what is used in Starliner and most other spacecraft, which makes it much cheaper and more reliable.
The researchers claim that, with the right ratio of helium to fuel, the engine could generate more than three times the thrust as that created using the fuel on its own. Remotely altering the amount of helium entering the engine could also theoretically allow its user to change the speed of any potential rocket midflight — making it harder for others to track or intercept it.
The new engine would also theoretically generate less excess heat. The researchers claim that its exhaust plume could be up to 2,880 degrees Fahrenheit (1,600 degrees Celsius) cooler than that of an equivalent rocket. If the engine is used to create missiles, this would make the weapon almost invisible to current early-warning systems, such as SpaceX's Starshield satellites, which identify and track missiles using their infrared signatures, according to Interesting Engineering.
Potential applications
This is not the first time this technology has been revealed to the world. In September 2024, the same research group published a paper in the American journal Physics of Fluids that demonstrated this engine's theoretical capabilities (and also hints that the idea could have originated before the Starliner fiasco, given how long it normally takes to publish scientific papers).
The faulty Starliner capsule was returned to Earth without passengers on Sept. 7, 2024. (Image credit: NASA TV) 請至原網頁觀看照片
However, unlike the earlier study, which focused more on how helium injection could increase thrust, the new paper emphasizes the potential application in stealth weaponry, highlighting its abilities to evade detection and avoid countermeasures.
This is not the only potential application, however. Because solid-fuel rockets are cheaper than liquid-fuel rockets, the new engine could drastically cut the cost of sending rockets into space, which could be a game changer considering the recent increase in the rate of launches globally.
These developments could help China establish its secretive "Thousand Sails" satellite constellation, which is starting to take shape in low-Earth orbit — and drawing ire from astronomers due to its high levels of light pollution.
China is also planning to build a human base on the moon by 2035 and will launch its first giant reusable rockets later this year to help achieve that goal. If the new technology were incorporated into this mission, it could reduce costs and help the country realize its lunar ambitions.
Harry Baker is a U.K.-based senior staff writer at Live Science. He studied marine biology at the University of Exeter before training to become a journalist. He covers a wide range of topics including space exploration, planetary science, space weather, climate change, animal behavior and paleontology. His recent work on the solar maximum won "best space submission" at the 2024 Aerospace Media Awards and was shortlisted in the "top scoop" category at the NCTJ Awards for Excellence in 2023. He also writes Live Science's weekly Earth from space series.
Related:
China plans to build enormous solar array in space — and it could collect more energy in a year than 'all the oil on Earth'
China's secret space plane has released another unknown object over Earth
本文於 2025/03/03 09:39 修改第 1 次
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千帆星座發射第四批衛星群 -- Andrew Jones
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2025/03/02 17:08 推薦1 |
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請參考千帆星座。
China launches fourth batch of Thousand Sails megaconstellation satellites
Andrew Jones, 01/23/25
A Long March 6A rocket lifts off from Taiyuan, Jan. 23, 2025, carrying 18 Qianfan satellites into polar orbit. Credit: CASC請至原網頁觀看照片
HELSINKI — China launched the fourth batch of 18 satellites for the Thousand Sails megaconstellation early Thursday using a Long March 6A rocket.
The Long March 6A lifted off at 12:11 a.m. Eastern (0511 UTC) Jan. 23 from Taiyuan Satellite Launch Center in north China, carrying 18 Qianfan (Thousand Sails) Polar orbit group 6 satellites into orbit. The China Aerospace Science and Technology Corporation (CASC), which produced the launcher, confirmed launch success in a post-launch statement.
THe 18 flat panel satellites are part of the Thousand Sails megaconstellation to provide low Earth orbit internet services. The project is led by Shanghai Spacecom Satellite Technology (SSST). The project is sometimes also referred to as Qianfan and G60 Starlink. The launch followed earlier Thousand Sails/Qianfan constellation satellite launches in August, October and December 2024.
There are now 72 Qianfan satellites in orbit. SSST, or Spacesail, plans to construct a constellation of 14,000 satellites, including having around 600 in orbit by the end of 2025. Spacesail has garnered substantial support, securing approximately $943 million in funding in early 2024. Genesat, a satellite manufacturing subsidiary of Spacesai, secured $137 million in funding in late December. The satellites launched today are thought to have been manufactured by the Shanghai Engineering Center for Microsatellites.
Of the three batches already in orbit, the first batch of 18 satellites have mostly raised their orbits from around 800 kilometers to around 1,060 kilometers in altitude, according to U.S. space tracking data. The second batch have so far performed little orbit raising, suggesting issues with the satellites. All satellites are in orbits inclined by 89 degrees.
CASC said it plans to launch more than 10 Long March 6A rockets this year. Last year it launched five; three of which were for Spacesail. Ten Long March 6A rockets have now been launched in total since its debut in 2022.
The Long March 6A, developed by SAST, is the first and so far only Chinese launcher to bundle a liquid propellant core stage with solid propellant side boosters. It is capable of launching 4,500 kilograms of payload to a 700-kilometer sun-synchronous orbit.
The rocket has, despite successful launches, suffered apparent issues with its upper stage fragmenting. The upper stage for the launch which carried the first 18 Qianfan satellites broke up into a cloud suspected to number more than 700 pieces of orbital debris.
The first launch of satellites for another, state-owned Chinese megaconstellation, Guowang, took place mid-December.
The mission was China’s fifth orbital launch attempt of 2025. It follows the launch of the Shijian-25 spacecraft servicing satellite Jan. 6, the sea launch of 10 navigation augmentation satellites Jan. 13, a remote sensing satellite for Pakistan and two smaller domestic satellites, and a Ceres-1 launch of five commercial satellites earlier this week.
CASC has yet to publish an overview of China’s overall plans for the year, but it may once again attempt to reach around 100 launches, as targeted for 2024.
Major missions for 2025 include crewed Shenzhou-20 and -21 missions and Tianzhou cargo spacecraft to the Tiangong space station and the Tianwen-2 near-Earth asteroid sample return mission. The latter is expected to launch around May. China also aims to debut a number of new Long March and potentially reusable commercial rockets during 2025.
Andrew Jones covers China's space industry for SpaceNews. Andrew has previously lived in China and reported from major space conferences there. Based in Helsinki, Finland, he has written for National Geographic, New Scientist, Smithsonian Magazine, Sky...More by Andrew Jones
本文於 2025/03/02 17:09 修改第 1 次
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「千帆星座」衛星互聯網 ---- 千帆星座中國航天衛星互聯網
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2025/03/02 10:40 推薦1 |
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請參看這篇報導(2025/02/21)。
1.5萬顆衛星 手機直連 「千帆星座」衛星互聯網覆蓋全球
千帆星座中國航天衛星互聯網，編輯︰許可，刊登日期 : 2024-12-01
衛星互聯網離生活不遠了！中國的「千帆星座」就計劃2030年底前發射多達1.5萬顆衛星，讓衛星互聯網覆蓋全球，屆時大家不管身在何處，只要看到天空，便能直接用智能手機上網。
「千帆星座」：低軌衛星作「基站」
「千帆星座」正在組網，預計2030年底完成。圖為第二批「千帆星座」組網星2024年在太原衛星發射中心升空 。（網上圖片）請至原網頁觀看照片
目前互聯網服務要靠光纖網絡、要建基站，但基礎建設必然受到地理環境、成本等制約，難以全面覆蓋，例如移動通信服務，至今僅覆蓋不足6%的地表面積。所以一旦離開人類生活主要區域，例如到了沙漠、山區或海洋，很可能出現「無網之災」。
如何能讓互聯網覆蓋全球、讓人們在任何地方都能上網呢？理想的辦法是使用近年正高速發展的衛星互聯網；簡單來說，衛星互聯網就是把互聯網信號傳上太空中的低軌衛星，並以衛星作「基站」，把信號轉發放到地面。
低軌衛星是指在距離地面表面160公里至2,000公里之間軌道運行的衛星。
它的覆蓋比不上距地球3萬多公里的地球同步衛星，需要較多星來組網來補足。惟它距離地球近，有運作成本低、信號傳輸功率損耗低、時延低等優勢，更適合發展互聯網服務。
「千帆星座」：一箭多星降低成本
「星鏈」和「千帆星座」都採用一箭多星技術發射，節省成本。圖為大批「星鏈」衛星堆疊在火箭分配器上。（網上圖片）請至原網頁觀看照片
早於上世紀90年代，美國摩托羅拉便有「銥星」計劃，用66顆低軌衛星覆蓋全球，只是因為使用成本高、頻寬追不上發展需要等原因，計劃未算成功。
此後美國SpaceX在2014年推出的「星鏈」，應該是航天迷最熟悉的衛星互聯網計劃了。
該公司透過規模化生產衛星、一箭多星、使用可重複使用火箭等方法降低成本，截至2024年7月已累計發射185批、6,805顆衛星，是部署規模最大的衛星互聯網星座，且其衛星發射頻率和數量都在增加，其終極目標是驚人的4.2萬顆。
同樣是2024年7月的數據，「星鏈」已為99個國家提供衛星互聯網服務，用戶突破300萬。當然，該公司的重要客戶，還包括美國軍方。
「千帆星座」：「星鏈」有力競爭者
「千帆星座」預計2025年底實現648顆星的區域覆蓋。圖為「千帆星座」的平板式衛星示意圖。（網上圖片）請至原網頁觀看照片
在「星鏈」以外，美、英、俄等國家都有公司或機構在發進類似計劃，而作為航天和科技大國的中國，在該領域當然有「大手筆」。
中國衛星互聯網的發展始於「十三五」期間（2016至2020年），踏入2024年，國家更把衛星互聯網納入「新基建」範籌，大力推動。
據報道，中國向國際電信聯盟申請的低軌衛星量已達5.13萬顆，其中涉及超過1萬顆的衛星互聯網計劃有3個，當中最受關注是全面建設中的「千帆星座」，它被形容為「中國版星鏈」，也將是這巨大市場的有力競爭者。
「千帆星座」又稱為「G60星座」，由成立於2018年的上海垣信衛星牽頭建設，於2019年開始發射試驗星，2024年8月由「長征六號改」火發射首批共18顆組網星，同年10月第二批18顆組網星亦升空。
「千帆星座」｜將以可重用火箭發射
「千帆星座」未來將借助可重複使用火箭來組網。圖為試驗中的其中一款可重複使用火箭「朱雀三號」。（網上圖片）請至原網頁觀看照片
「千帆星座」同樣會以批量生產、一箭多星等方法降低成本，未來還將換用國產的可重複使用火箭發射衛星。按計劃，它將於2025年底實現648星的區域覆蓋，2027年實現第一階段1,296星的全球覆蓋，至2030年底完成約1.5萬顆衛星布局，為全球提供衛星互聯網服務。
該公司負責人表示，完成第一階段全球覆蓋後發射的衛星，軌道高度將從1,000多公里降到300至500公里，「那麽離地球表面更近，具備了提供手機直連、寬窄帶物聯網更高級的應用」。
「手機直連」（Direct to Cell，DTC）是指直接用手機收發使用互聯網信號，不需要其他接收和發射裝置作中介，亦即用戶不管在任何地方，只要看到天空，都能直接用手機上網。
比「千帆星座」起步更早的美國「星鏈」，當然也朝「手機直連」方向發展。該公司的衛星互聯網已投入商用，惟現階段仍需要使用接收天線，再經路由路器發送信號給手機。
「千帆星座」：2026年為巴西提供服務
「千帆星座」2026年為巴西提供服務，圖為雙方代表簽署協議。（網上圖片）請至原網頁觀看照片
目前華為一些型號智能手機能直接衛星，然而它們和傳統衛星電話一樣，只支援語音，不能連上互聯網。另外，中國的北斗衛星是導航系統，它雖然可以收發短報文和語音簡訊，但與上網是兩回事。
據悉，在2024年底，「千帆星座」方面已與巴西國有企業簽署合作備忘錄，於2026年為當地的偏遠和網絡不發達地區提供互聯網服務。
除了「千帆星座」，中國的「鴻鵠星座」和「中國星網」亦有逾萬顆星的衛星互聯絡計劃。
最後必須一提，空間軌道和無線電頻率都是不可再生資源，故衛星營運商要「先到先得」向國際電信聯盟申請，並必須在7年內發射第一顆星、9年內發射總數達到10%、12年內達到50%，並須於14年內完成整個星座發射。
延伸閱讀：
中國驗證火箭重複使用技術 追趕美國SpaceX 未來發射成本或減半
本文於 2025/03/02 10:41 修改第 1 次
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