china constellation

china constellation插图

Chinese constellations (Chinese: 星官,xīngguān) are the groupings used by the ancient Chinese to organize the stars. They are very different from the modern International Astronomical Union-recognized constellations based on Greco-Roman astronomy. Ancient Chinese skywatchers divided their night sky into 31 regions:the Three Enclosures (三垣,Sān Yun) and the Twenty-Eight Mansions(二十八|宿,rshbā Xi ). [1]

How many satellites will China’s GW constellations build?

Spectrum allocation filings submitted to the International Telecommunication Union (ITU) by China in September last year revealed plans to construct two similarly named “GW” low Earth orbit constellations totaling 12,992 satellites.

Who are the contractors involved in China’s new space constellation?

Currently no details have been released on the contractors to be involved in the constellation. Notably the China Satellite Network Group will exist independent from and parallel to China’s main space contractors, the China Aerospace Science and Technology Corp. (CASC), and the China Aerospace Science and Industry Corporation (CASIC).

What will GW constellation look like?

The filings indicate plans for GW to consist of sub-constellations ranging from 500-1,145 kilometers in altitude with inclinations between 30-85 degrees. The satellites would operate across a range of frequency bands. Currently no details have been released on the contractors to be involved in the constellation.

What are the concerns of megaconstellations?

Proposed and developing megaconstellations are raising concerns of the heightened risk of orbital debris. The growing number of satellites in LEO is also a threat to visible astronomy.

How high is the GW satellite?

The filings indicate plans for GW to consist of sub-constellations ranging from 500-1,145 kilometers in altitude with inclinations between 30-85 degrees. The satellites would operate across a range of frequency bands.

What is the 14th Five-Year Plan?

The recently approved 14th Five-year Plan for the period 2021-2026 and “long-range objectives through 2035” call for an integrated network of communications, Earth observation, and navigation satellites.

Who is the president of China Spacesat?

On Monday Ge Yujun, president of China Spacesat Co., Ltd., a CASC subsidiary, told ThePaper that the Hongyan and Hongyun broadband constellations previously planned CASC and sister state-owned giant China Aerospace Science and Industry Corporation (CASIC) respectively would be altered by authorities.

Which country has the Beidou satellite?

China has already constructed its Beidou navigation and positioning system and is deploying Gaofen satellites for its China High-resolution Earth Observation System (CHEOS).

When will the Hongyan-1 satellite launch?

The Hongyan-1 satellite ahead of launch in 2018. Credit: CAST

Who is Bao Weimin?

Bao Weimin, a senior official with the China Aerospace Science and Technology Corp. (CASC), China’s main space contractor, made a first public acknowledgement of the megaconstellation plan in an interview with Shanghai Securities News March 7, stating “we are planning and developing space-based internet satellites and have launched test satellites.”

Imperial Order

The Western system used Greek legends for naming the constellations, there is no overall organization for the stars, although some constellations have linked origins such as Pegasus, Perseus and Andromeda. By contrast, China developed an impressively consistent scheme.

Chinese Planets

To the Chinese the planets do not hold as much importance as the stars and they are named with the five Chinese elements: Mars with fire 火 星 ‘fire star’; Jupiter with wood 木 星; Venus with metal 金 星; Mercury with water 水 星 and Saturn with earth 土 星.

Ancient Observations

It was the famous scientist Laplace ? who said “ Of all the ancient peoples, the Chinese have the most ancient records of the science of astronomy ”.

Birth stars

Celestial Buddhas and Deities of the Northern, Western, and Central Dipper Constellations. c.1500CE. Image by LACMA ? available under a Creative Commons License ?

The Chinese Days of the Month or Mansions

The twenty-eight mansions of the Chinese astronomy. May 2008. Image by Mysid ? available under a Creative Commons License ?

What is the name of the constellation of China Spacesat?

The president of China Spacesat Co., Ltd., a CASC subsidiary, said in April that constellation plans by both CASC and CASIC would “undergo major changes” following the move to create the Guowang constellation .

What is the SASTIND notice?

In a related development the State Administration of Science, Technology and Industry for National Defense (SASTIND), which oversees areas of the country’s space activities, also issued a notice on promoting the orderly development of small satellites May 19. The document provides a level of guidance to commercial companies and is another step in setting regulations for China’s growing space activities.

How high is the GW satellite?

The filings indicate plans for GW to consist of sub-constellations ranging from 500-1,145 kilometers in altitude with inclinations between 30-85 degrees. The satellites would operate across a range of frequency bands.

What is China’s LEO constellation?

China’s previously announced plans for LEO constellations have stated providing communications for Belt and Road countries and rural areas. The development is the latest in a line of policy directions and actions to develop a low Earth orbit communications constellation.

What is the SASAC?

The State-Owned Assets Supervision and Administration Commission (SASAC), a government body overseeing state-owned enterprises, issued a press release April 29 announcing the creation of the China Satellite Network Group Co. Ltd. The move follows comments from senior space industry officials earlier in the year that a company will be formed …

Where is China Satellite Network Group located?

China Satellite Network Group is to be based in Xiong’an New Area, a state-level new area in the Baoding area of Hebei, China, created in 2017.

Is China satellite network independent?

Notably the China Satellite Network Group will exist independent from and parallel to China’s main space contractors, the China Aerospace Science and Technology Corp. (CASC), and the China Aerospace Science and Industry Corporation (CASIC). The apparent independence of China Satellite Network Group from CASC and CASIC indicates that other actors, …

How close are SpaceX and OneWeb?

This month, satellites from OneWeb and SpaceX came within 190 feet of each other – after both companies coordinated to avoid a devastating collision.

How many satellites will China launch in the future?

Xie Tao, founder of Beijing Commsat Technology Development Co., Ltd, told China Money Network he expects the country to launch 30,000 to 40,000 Satellites in the future, compared to 40,000 to 60,000 launched by the US.

How many satellites are in orbit?

Of the 3,000-odd operational satellites currently in orbit, a little over 400 belong to China or Chinese companies. The number of commercial companies in the West launching satellites has skyrocketed in recent years, and SpaceX now operates more satellites than any other company or government.

How do you dispose of satellites?

There are no international laws regarding satellite disposal, and ESA estimates non-compliance around disposal could be as high as 60 percent of launches. Poor adherence to End of Life protocols can also add to the issue of space junk. In LEO, best practice is to have your satellite descend to an orbit where it will naturally burn up in the atmosphere; some even have propulsion systems that can get them there faster, some even have small parachutes which can slow their speed and de-orbit them quicker. At GEO, it’s more common to have satellites fly into a higher orbit out of harm’s way.

How fast did the Iridium 33 and Kosmos-2251 collide?

In 2009, the Iridium 33 and the defunct Russian military Kosmos-2251 satellites collided at a speed of 11,700 m/s (26,000 mph; 42,000 km/h) and an altitude of 789 kilometers (490 mi). Kosmos-2251 had gone out of service in 1995, had no propulsion and no one controlling it. The resulting collision created at least 2,000 pieces of large debris, forcing the International Space Station to change orbit to avoid pieces. More than one thousand pieces still remain in orbit.

What are the risks of Chinese satellites?

Chinese commercial satellites are subject the same risks as Western ones in space; extreme temperatures, crowded operating environment, and new companies seeing large numbers of failures as they go through rapid development. But a lack of proper registration can create more risk of collisions, which can have catastrophic effects, especially with larger satellites at higher orbits.

What happened to the semiconductor industry in Texas?

Texas froze over, data centers burned down, and semiconductor fabs struggled with drought. The last three months have been chaos, but data center resiliency has helped the industry prevail.

How far apart are the Yaogan 30T and 30S?

Normally the three satellites in a plane are phased 120° apart to maximize coverage, but currently Yaogan 30T and Yaogan 30S are very close to each other, making one of the two redundant. The redundant one is 30T, as can be seen by comparing the orbital elements of the sixth trio:

How many satellites are needed for Belt and Road?

The second step is regional coverage of China and surrounding countries along the Belt and Road. This requires about 100 remote sensing satellites. Among them, half of the remote sensing satellites are optical satellites and half are radar satellites to ensure that there are images during the day and night, plus 150 communication satellites;

What is Li Deren’s future development?

Li Deren also explains that future developments will integrate the traditionally separated functions of observations, communications and location services, and provide this data directly to end-users’ phones to minimize latency and thus maximize its impact:

How long is the gap between satellites?

So over a 24h window, the coverage is almost constant, with the biggest gap being around 30 minutes, and most gaps being 10 minutes every half an hour. The following video shows the position of the satellites and the coverage opportunities (as a purple link between the satellite and the ground) over time:

Is Yaogan 30T phased correctly?

The other peculiarity of the constellation is that one of the satellites of the sixth group failed, or at least its propulsion failed: Yaogan 30T (international designator 2020-021C) is not phased correctly in its plane. Normally the three satellites in a plane are phased 120° apart to maximize coverage, but currently Yaogan 30T …

What is Eastpendulum.com about?

This article initially appeared on eastpendulum.com, a French-language blog about the Chinese military and aerospace industry

Does 30T move?

30T has not maneuvered at all since reaching orbit and consequently does more revolutions per day (called mean motion) than the other two, meaning its is constantly moving around in the orbital plane. The fact that it is close right now to 30S is a coincidence, it will move further and further apart over time.