Friday, October 14, 2016

China Set to Launch the Shenzhou-11 Crewed Mission with Two Taikonauts Aboard

Shenzhou-11 spacecraft undergoing tests in February 2016. Photo Credit: CCTV

Under a shroud of secrecy, China is completing final steps towards the launch of its Shenzhou-11 spacecraft with two taikonauts on board. On Monday, Oct. 10, the country has rolled out the Long March 2F rocket that will be used to send the crewed mission into space.

Although China has not yet disclosed the exact date of the liftoff, it is predicted that the rocket will launch around 7:30 a.m. local time on Monday, Oct. 17 (23:30 GMT; 7:30 p.m. EDT on Oct. 16), from Launch Area 4 at the Jiuquan Satellite Launch Centre in the Gobi Desert.

Shenzhou-11 is China’s sixth manned space mission. The longly anticipated flight ends the country’s three-year period of absence in human spaceflight, as the last crewed vehicle – Shenzhou-10 – was launched from the Chinese soil in June 2013.

However, although the mission is of high importance for China, the officials are very reluctant to reveal details about the upcoming flight. To this date, only a handful of information has been disclosed about the crew of Shenzhou-11. It was earlier announced that two male taikonauts will fly aboard the craft; however, their names are kept under wraps and could be announced even hours before liftoff.

Having in mind the requirement that Shenzhou missions always include an experienced spacefarer, Nasaspaceflight.com speculates that the most likely candidates are the following: Liu Boming, a veteran of Shenzhou-7 and the commander of the Shenzhou-10 backup crew; Liu Wang, who flown on Shenzhou-9; or Zhang Xiaoguan, a member of the Shenzhou-10 crew.

The site reports that the second spot is even less certain as it could be occupied by a second taikonaut with spaceflight experience or one unflown member of the original 1998 group, such as Deng Qingmin or Pan Zhanchun, who both were part of the Shenzhou-10 backup crew.

Regardless of the composition of the flight crew, the Shenzhou-11 mission will be sent into space with a clear goal of docking with the Tiangong-2 orbital laboratory that was launched one month ago. The spacecraft is slated to dock with the space lab two days after launch.

The duo of taikonauts will enter the Tiangong-2 module and stay inside for 30 days, testing advanced life support systems and conducting various science experiments. It will be China’s longest stay in space to date. The two-person crew will probably return to Earth on Nov. 14.

In order to enable such one-month stay in space, China decided to downsize the crew from three to two. Previous missions, like Shenzhou-9 and Shenzhou-10, consisted of three taikonauts orbiting the Earth for two weeks.

“This is going to provide evidence of astronauts' long-term stay in space for the development of China's space station in the future," Lei Fanpei, chairman of the China Aerospace Science and Technology Corporation (CASC), told CCTV.

China indeed hopes that Shenzhou-11, together with Tiangong-2, will bring the nation closer towards building its own permanent space station, as they will enable testing key technologies before sending a larger module into orbit. The station is expected to be built sometime between 2018 and 2022.

The start of the Shenzhou-11 mission was postponed several times as its launch was dependent on the Tiangong-2 which suffered a series of delays. First rumors about the exact launch date appeared in November 2013, targeting May 2016 for liftoff.

The mission campaign commenced on Aug. 3 with the arrival of the Long March 2F rocket at Jiuquan. The launch vehicle was delivered from Beijing by train, while the Shenzhou-11 spacecraft was transported from China’s capital city to the center by plane on Aug. 13.

With both the rocket and the spacecraft in place, the engineers began a period of busy pre-launch activities, including initial tests and checkouts. However, very little is known about this phase of preparations as Chinese media has not revealed any details regarding these operations. It was only revealed that the rollout of the rocket, from the assembly facility to the launch site, was carried out on Oct. 10.

The Shenzhou-11 crewed vehicle has a mass of about 8.1 metric tons and comprises of an orbital module, a return module and an engineering module. Although developed indigenously by China, the spacecraft’s design is based on the Russian Soyuz capsule.

The first Shenzhou spacecraft was sent into space in November 1999. It was an unmanned automated test flight like the next three Shenzhou missions, conducted between January 2001 and December 2002.

Shenzhou-5 mission, launched in October 2003, was China’s first manned spaceflight in history. The spacecraft sent Yang Liwei into orbit for about 21 hours, making him the first Chinese in space.

Two years later, the Shenzhou-6 spacecraft delivered a two-person crew into orbit on a five-day mission. Three taikonauts were launch by China for the first time in September 2008 onboard the Shenzhou-7 vehicle. During this mission, Zhai Zhigang performed the first Chinese spacewalk.

From 2011 to 2013, the country conducted three Shenzhou missions - one every year. Shenzhou-8, launched in October 2011, was an automated test of rendezvous and docking with the Tiangong-1 - China’s first space laboratory, delivered into space one month earlier.

Shenzhou-9 and 10 both carried three-person crews and both docked to the Tiangong-1 module. Shenzhou-9 was launched in July 2012, while Shenzhou-10 in June 2013.

The Tiangong-2 space laboratory that will be visited by the Shenzhou-11 crew, was launched into orbit on Sept. 15, 2016. It will enable testing key technologies before sending a larger module into orbit. Besides being visited by the Shenzhou-11 crew, the laboratory will dock in April 2017 with the new Tianzhou-1 cargo ship that will deliver fuel and supplies.

The 170 feet (52 meters) tall Long March 2F rocket, which will be used to launch Shenzhou-11 into space, is 11 feet (3.35 meters) in diameter and weighs around 464 metric tons. It is a two-stage rocket capable of sending up to 8.4 metric tons into a low-Earth orbit (LEO). For Monday’s launch, the rocket will fly in 2F/G configuration that was specially designed to launch space laboratories such as Tiangong. It features a launch escape system and has a larger fairing to accommodate larger payloads.

The rocket’s first stage is 78 feet (23.7 meters) long and 11 feet (3.35 meters) in diameter. This stage is fitted with four YF-20B engines burning for two minutes and 46 seconds. Four strap-on boosters are attached to the first stage, powered by one YF-20B engine each.

The second stage – 44-feet (13.5 meters) long and 11 feet (3.35 meters) in diameter – is equipped with one YF-24B engine. During the flight, this stage burns for about five minutes.

Monday’s launch will be the 237th flight of the Long March rocket and the 15th orbital mission conducted by China this year. The next Chinese missions are currently scheduled for November when the country plans to conduct a maiden flight of its Long March 5 booster and will perform one launch of its Long March 2D rocket, carrying the country’s Hard X-ray Modulation Telescope (HXMT). However, China launches many missions unannounced; therefore, an unexpected liftoff could be also carried out in October.

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