Beidou-3 M1 (№24), Beidou-3 M2 (№25) – CZ-3B – Сичан (XSLC) – 05.11.2017, 11:34 UTC

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Chris B - NSF‏ @NASASpaceflight 4 мин. назад

LIFTOFF CONFIRMED: Long March 3B returns with dual Beidou-3 mission - https://www.nasaspaceflight.com/2017/11/long-march-3b-returns-dual-beidou-3-mission/ ... - by Rui C. Barbosa As per usual, the Chinese media won't acknowledge this launch until S/C Sep, which is about four hours away.

Long March 3B returns with dual Beidou-3 mission

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Ушла примерно в 19:45 пекинского.

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Andrew Jones‏ @AJ_FI 1 мин назад

Liftoff of the Long March 3B carrying 2 Beidou sats from Xichang. Some amateur pics and later footage here. Confirmation to come later.

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ChinaSpaceflight‏ @cnspaceflight 4 ч.

Video (0:12)

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https://gbtimes.com/china-launches-two-beidou-satellites-in-return-to-flight-for-long-march-3b-rocket

China launches two Beidou satellites in return to flight for Long March 3B rocket
by Andrew Jones Nov 05, 2017 14:40 SICHUAN PROVINCE WENCHANG TIANGONG-2

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Liftoff of the Long March 3C rocket taking the Beidou-3 navigation satellite. The mission launched from the Xichang Satellite Launch Center in Sichuan Province at 21.50 Beijing time on March 31, 2015. CNS

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China on Sunday added two more satellites to its Beidou navigation and positioning system following the launch of a Long March 3B rocket from Xichang launch centre.
The launch vehicle lifted off from Xichang in the hills of southwestern Sichuan Province around 11:40 UTC (19:40 Beijing time), with the satellites to be ins erted into prese t orbits by a Yuanzheng-1 upper stage.
With no launch coverage, the first indications of liftoff came from Chinese social media channels, including amateur footage.
Launch success is expected to be confirmed by Chinese state media within a few hours of liftoff.

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Andrew Jones‏ @AJ_FI 2 мин назад

Launch success confirmed: China lofts 2 Beidou satellites with return to flight of Long March 3B rocket. Article: https://goo.gl/8hqGYE 

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Andrew Jones‏ @AJ_FI 3 мин назад

Xinhua (Chinese) article confirming success (+details on Beidou accuracy, et): http://news.xinhuanet.com/politics/2017-11/06/c_1121908691.htm ...

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Статья Long March 3B returns with dual Beidou-3 mission обновлена

China successfully launched a new pair of navigation satellites – namely the Beidou-3M1 (Beidou-24) and Beidou-3M2 (Beidou-25) navigation spacecraft – on Sunday, using a Long March-3B/YZ-1 rocket that was marking its return. The launch took place at around 11:45 UTC from the LC3 Launch Complex of the Xichang Satellite Launch Center, Sichuan province. It took over four hours to complete the mission.
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http://news.xinhuanet.com/english/2017-11/06/c_136730074.htm

China launches two BeiDou-3 navigation satellites on single carrier rocket
Source: Xinhua | 2017-11-06 00:29:37 | Editor: yan


XICHANG, Sichuan Province, Nov. 5 (Xinhua) -- China launched two BeiDou-3 satellites into space via a single carrier rocket to support its global navigation and positioning network at 7:45 p.m. Sunday.

The satellites were aboard a Long March-3B carrier rocket which took off from Xichang Satellite Launch Center in the southwestern province of Sichuan.

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This is the first two BeiDou-3 satellites launched by China, as its self-developed BeiDou Navigation Satellite System officially began to expand into a global network.

Named after the Chinese term for the plough or the Big Dipper constellation, the BeiDou project was formally initiated in 1994. It began to serve China in 2000 and the Asia-Pacific region at the end of 2012.

China plans to building BeiDou into a global positioning and navigation system by around 2020, making it the third country in the world after the United States and Russia to operate its own navigation system.

Compared to earlier generation satellites, the BeiDou-3 is able to send signals that are better compatible with other satellite navigation systems and provide satellite-based augmentation, as well as search and rescue services in accordance with international standards.

"New technology has significantly improved the performance of the BeiDou-3, with the signal accuracy in space higher than half a meter while its positioning accuracy has reached 2.5 to five meters, said Yang Changfeng, chief designer of the BeiDou system.

China plans to launch 18 BeiDou-3 satellites around the end of 2018 to expand the BeiDou services to the countries along the Belt and Road routes.

By around 2020, when the system goes global, it will have more than 30 satellites.

"Launches featuring two or more satellites on a single carrier rocket will be conducted regularly," said Ye Chengmin, deputy chief designer of the Long March-3A carrier rocket.

All the BeiDou satellites currently in space were sent up from Xichang Satellite Launch Center, said Lin Yunan, head of the human resources department of the center.

The BeiDou-3 satellites and the carrier rocket were developed by China Academy of Space Technology and China Academy of Launch Vehicle Technology, respectively.

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[dimoncoder]

А spaceflightnow.com всё проспал...

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Как сообщают нам коллеги с NSF, единственное место, где можно найти статус и альманах спутников "Бэйдоу" -- это официальный сайт ГЛОНАСС :-)
https://www.glonass-iac.ru/en/BEIDOU/index.php

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dimoncoder пишет:
А spaceflightnow.com всё проспал...

У них выходной.

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http://spaceflight101.com/long-march-3b-launches-beidou-3-m1-m2/

Long March 3B Rocket Lifts off with two Chinese Navigation Satellites
November 5, 2017

A Chinese Long March 3B rocket lifted off from the country's Xichang Satellite Launch Center around 11:44 UTC on Sunday, embarking on a multi-hour climb into an orbit over 21,000 Kilometers in altitude to dispatch a pair of Beidou-3 navigation satellites to join China's global navigation satellite system currently undergoing deployment.

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File Image of a Long March 3B launching from Xinhua – Photo: Xinhua

Sunday's launch was the eleventh Chinese orbital space launch in 2017 and the first in support of Beidou this year with another dual-satellite launch planned in December to be followed by at least six Beidou launches in 2018 to accelerate the pace of deployment. The launch also marked the opening salvo in China's typical end-of-year frenzy with six launch campaigns currently underway at the country's inland launch bases to set up for missions in the coming weeks.

Outfitted with a Yuanzheng-1 upper stage on Sunday, the Long March 3B rocket departed the Xichang launch site in the Sichuan Province to the south-east, flying across the Chinese mainland before heading out over the Pacific Ocean. The three-stage Long March 3B was to deliver the stack into an elliptical transfer orbit followed by a supplementary burn by the YZ-1 stage to set the proper apogee altitude of the transfer orbit before a coast phase of over three hours to fire the upper stage again when reaching the high point of the orbit to dispatch the satellites into a circular orbit.


Beidou-3 – Global Constellation – Image: beidou.gov.cn

Given the launch profile used on Sunday, official confirmation of the outcome of the mission is not expected until around four hours after liftoff.

The Chinese Beidou Navigation Satellite System employs a combination of satellites in Geostationary Orbit, inclined Geosynchronous Orbits and Medium Earth Orbit as opposed to purely MEO-based systems like the U.S. GPS, Europe's Galileo and Russia's Glonass and Geostationary-only constellations like India's IRNSS 'Navic.' Beidou finds its roots back in 1983 when the first proposals for a Chinese navigation system were made, but the program's first launch did not occur until 2000.

Beidou has been laid out as a three-step program in a gradual evolution from an experimental regional system to operational regional coverage and eventually global, 24/7 coverage. The initial step utilized three satellites placed in Geostationary Orbits within visibility of China to begin navigation services limited to the Chinese territory with an accuracy of around 20 meters.


Biedou-3 Satellite Types – Image: beidou.gov.cn

To expand this system to the Asia-Pacific Region, Beidou-2 was inaugurated in 2009 with five satellites in GEO, five in inclined Geosynchronous Orbits plus several more in Medium Earth Orbit, broadening the systems coverage area and improving its accuracy. The third and final stage of establishing a space-based navigation architecture is the expansion to a continuous global coverage at very high accuracy by using satellites deployed to different orbits.

Known as Beidou-3, the finished constellation will be comprised of 27 Beidou-3M satellites in Medium Earth Orbit, five Beidou-3G satellites in Geostationary orbit and three Beidou-3I satellites in inclined Geosynchronous orbits. Seven Beidou-3 satellites have launched before Sunday – one to GEO, three to IGSO and three to MEO.

The Beidou-3 constellation uses two types of satellites by two different manufacturers (CAS & CAST) with the first from each classed as in-orbit validation missions.

All three prior MEO launches under Beidou-3 were classed as in-orbit validation missions with Sunday's launch involving the first pair of operational satellites. At least a dozen MEO satellites are on China's launch manifest through the end of 2018 to bring Beidou-3 to an initial operational capability on a path toward full operational capability in 2020.

>> Beidou-3 Satellite & Constellation Overview


First Beidou 3-M Satellite during Integration – Photo: SASTIND

The Beidou-3 system has been designed to operate from multiple orbits to provide compatibility with the previous Beidou generations. To that end, the Geostationary and Geosynchronous satellites carry two navigation payloads, the Radio Determination Satellite Service retained from Beidou-1 to provide compatibility with heritage receivers and the Radio Navigation Satellite Service.

The Radio Navigation Satellite Service operates in a similar way as the Galileo, GPS, Glonass and IRNSS navigation systems – sending coded signals in the L-Band frequency with ultra high timing precision so that receivers on the ground can process three or four different signals in order to calculate the user's precise position, elevation and speed.

The Medium Earth Orbit Satellites carry only the Radio Navigation Satellite Service payload allowing them to be smaller in size than the high-altitude satellites and their two payloads.


Original DFH-3 Platform – Image: CAST

They weigh 1,014 Kilograms and are based on a newly developed satellite bus smaller than the DFH-3 platform, but using a number of DFH-3 heritage components to match its capabilities and reduce risk. The three-axis stabilized satellites accommodate a payload mass of 280 Kilograms and measure 2.25 by 1.0 by 1.22 meters in size. Two deployable solar arrays generate 1,500 Watts of of power.

The Medium Earth Orbit satellites are deployed to an orbit of 21,500 Kilometers inclined 55 degrees and the finished constellation will feature three orbital planes with nine satellites per plane to guarantee global coverage.

Deployment of the Beidou-3 constellation primarily relies on China's heritage launch vehicle, namely the Long March 3 family that can launch pairs of MEO satellites with help of the YZ-1 upper stage while GEO/GSO satellites either use the YZ-1 upper stage for a direct injection or start out in a transfer orbit and raise their orbits themselves. China's new heavy-lift rocket, Long March 5, could lift four MEO satellites using a YZ-2 upper stage; however, a recent failure will prevent the vehicle from being declared operational for some time.

>> Long March 3B Launch Vehicle


Photo: Xinhua (File)

The 56.3-meter tall Long March 3B lifted off from Xichang at 7:44 p.m. local time, climbing vertically for a few seconds before aligning itself with a south-easterly trajectory, taking it over the Yunnan, Guizhou and Guangxi provinces, the Gulf of Tonkin, Hainan Island and out over the Pacific Ocean.

With its four liquid-fueled boosters and large core stage firing at full throttle, the Long March 3B had a total launch thrust of 604 metric-ton-force as it departed Xichang, en-route to an initial Parking Orbit.

The four boosters, 16.09 meters long and 2.25 meters in diameter, were to fire for two minutes and 20 seconds – each delivering 740 Kilonewtons of additional thrust and burning through 41,100 Kilograms of hypergolic propellants. After separation of the boosters, the vehicle was to continue ascent powered by the stage alone, fitted with a four-chamber DaFY-6-2 engine cluster providing 2,961 Kilonewtons of thrust. The stage stands 24.76 meters tall and holds 186,200 Kilograms of propellants at liftoff enabling it to burn for 158 seconds.

Separation of the stages was planned to occur in hot mode, starting with the ignition of the second stage's vernier engine and followed by the firing of cutting charges to allow the spent core to be discarded and the second stage to fire up its main engine. The 12.9-meter long second stage, holding 49,000kg of propellants, was expected to burn for nearly three minutes with a total thrust of 742 Kilonewtons.

Assuming control of the flight, the third stage was to ignite its YF-75 dual engine cluster that, unlike the other CZ-3B stages, burns Liquid Oxygen and Liquid Hydrogen. Generating 157 Kilonewtons of thrust, the third stage was to burn through 18,200 Kilograms of cryogenics over the course of one or two burns to raise put the stack into an elliptical transfer orbit for separation of the YZ-1 Upper Stage.


YZ-1 Upper Stage carrying the first Beidou-3 IGSO Satellite – Image: CCTV

The Yuanzheng-1 (Expedition-1) upper stage has been developed as a multi-purpose vehicle capable of executing mission profiles with several engine burns over extended mission durations. Using storable propellants, the main engine of the YZ-1 stage delivers 6.5 Kilonewtons of thrust and supports at least two in-space engine starts – first to finish the parking orbit insertion and setting the proper altitude and again for the circularization after an extended coast phase. Injection of the Beidou-3 M1 and M2 satellites is planned directly into their operational orbit around 21,500 Kilometers in altitude.

The next Chinese launch is set for November 15 when a Long March 4C rocket will deploy the Fengyun-3D weather satellite into a Sun Synchronous Orbit.

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Long March-3B launches two BeiDou-3 satellites

SciNews

Опубликовано: 5 нояб. 2017 г.

Two BeiDou-3 satellites were launched by a Long March-3B launch vehicle from the Xichang Satellite Launch Center, Sichuan province, on 5 November 2017, at UTC ( local time). To expand the BeiDou Navigation Satellite System, China plans to launch 18 BeiDou-3 satellites by the end of 2018. The system is planned to have global coverage by 2020, with more than 30 satellites.

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Время КП - 19:45:04.244 (Beijing Standard Time, UTC+8 )

ChinaSpaceflight‏ @cnspaceflight 2 ч назад

【北斗卫星】打码与不打码。

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https://spaceflightnow.com/2017/11/05/china-returns-long-march-3b-rocket-to-service-after-june-failure/

China returns Long March 3B rocket to service after June failure
November 5, 2017 Stephen Clark


A Long March 3B rocket lifts off from the Xichang launch base Sunday with two Beidou navigation satellites. Credit: Xinhua

China's Long March 3B rocket, used to power navigation and communications satellites into high-altitude orbits, launched for the first time in nearly five months Sunday with two spacecraft for the country's Beidou positioning network.

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Sunday's launch, declared a success by Chinese officials, marked the first flight of a Long March 3B since June 19, when a roll control error on the rocket's third stage led to the deployment of the Chinasat 9A television broadcast satellite into a lower-than-planned orbit.

The Chinasat 9A satellite later boosted itself into its originally-intended orbit, but at the expense of fuel, reducing its expected useful lifetime.

The June 19 failure was the third in a string of four Chinese launch accidents in a span of less than a year. Chinese space officials suspended all launches in early July after a heavy-lift Long March 5 rocket failed to enter orbit.

China's Long March 2-series rockets returned to service last month with two successful missions, while the larger Long March 3B remained grounded until Sunday.

Powered by four liquid-fueled strap-on boosters and a hydrazine-burning core stage, the Long March 3B lifted off at 1145 GMT (6:45 a.m. EST) Sunday from the Xichang space center in southwestern China's Sichuan province. The launcher apparently performed as designed.

After heading southwest from Xichang, the rocket's hydrogen-fueled third stage was expected to deploy a Yuanzheng space tug in an elliptical, oval-shaped orbit less than a half-hour after liftoff. The Yuanzheng upper stage was programmed to maneuver the two third-generation Beidou satellites in a circular 55-degree inclination orbit about 13,700 miles (22,000 kilometers) above Earth.

U.S. military tracking data on the satellites were not immediately available Sunday, but the government agency responsible for China's Beidou navigation system confirmed the flight was a success. Launch announcements from Chinese government sources are typically reliable.

Sunday's launch followed the deployment of two third-generation Beidou test satellites into a so-called medium Earth orbit in July 2015.

The completed Beidou constellation will consist of 27 satellites in medium Earth orbits, five in geostationary-type orbits around 22,300 miles (36,800 kilometers) over the equator, and three in inclined geosynchronous orbits that oscillate north and south of the equator.

The satellites launched Sunday are the 24th and 25th to join the Beidou fleet, which currently includes around 15 operational navigation craft, according to a roster kept by Russia's Information and Analysis Center for Positioning, Navigation and Timing that tracks the status of U.S., Russian and Chinese navigation networks.

When complete, the Beidou system will join the U.S. Air Force's Global Positioning System, Russia's Glonass satellite network, and Europe's Galileo fleet — which is still being deployed — as the world's four navigation services with global reach.

Named for the Chinese word for the Big Dipper constellation, the Beidou constellation achieved an initial operating capability with coverage over the Asia-Pacific region in 2012. Development of the Beidou program began in 1994.

The third-generation satellites now being launched by China feature higher-performance rubidium and hydrogen atomic clocks, inter-satellite links, improved spatial signal accuracy, better compatibility with other countries' navigation satellites, and offer search-and-rescue services, according to a Chinese government release published on the Beidou program's official website.

The Beidou satellites are designed to be interoperable with U.S., Russian and European navigation networks, and U.S. and international chipset producers offer receivers capable of using L-band signals from all four types of satellites. Combining signals from more satellites give users a more precise position estimate.

The third-generation Beidou spacecraft can provide positioning accuracies between 2.5 and 5 meters (8.2 to 16.4 feet), according to Chinese program officials.

China said it plans to launch 18 more Beidou satellites by the end of 2018, and the network will have more than 30 satellites by 2020, enough to begin independent global service.

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Ещё видео

https://www.newscctv.net/219news/video.html?videoId=63147E30-A3C9-2CC2-40F2-418250C63C1E

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http://news.xinhuanet.com/english/2017-11/06/c_136731697.htm

Better rubidium clocks increase BeiDou satnav accuracy
Source: Xinhua | 2017-11-06 15:32:55 | Editor: Yang Yi

XICHANG, Sichuan Province, Nov. 6 (Xinhua) -- New, ultra-accurate rubidium atomic clocks on board two BeiDou-3 satellites launched into space Sunday have greatly improved the accuracy of the system.

The two satellites are equipped with more reliable rubidium atomic timekeepers than those in previous BeiDou satellites. According to Yang Changfeng, chief designer of the satellite system, their stability was as high as E-14. "It means only one second of deviation in 3 million years," he said.

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Important payloads of the navigation satellites, atomic clocks are the workhorses which synchronize the signals that allow satnav receivers to triangulate their position on Earth.

"The stability of the new-generation clocks has been improved by 10 times, compared with those carried by BeiDou-2 satellites," said Qu Yongsheng from the China Aerospace Science and Technology Corporation fifth research institute, Xi'an branch, developer of the clocks.

Qu said this new technology has raised the positioning accuracy of the BeiDou-3 to 2.5 - 5 meters from 10 meters in the past.

Named after the Chinese term the Big Dipper constellation, the BeiDou project was formally initiated in 1994, began to serve China in 2000 and was expanded across the Asia-Pacific region at the end of 2012.

BeiDou is intended to become a global positioning and navigation system by around 2020.

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Интересно, эталоны частоты все швейцарские (SpectraTime) или только резервный комплект?