Shenzhou-9 successfully returns to Earth
June 28th, 2012 by Rui C. Barbosa
The three member crew of China's Shenzhou-9 have safely returned to Earth, following a successful – and historic – docked mission with the unmanned space module Tiangong-1. The crew – including China's first female taikonaut – touched down at the primary landing site in Inner Mongolia at around 2am UTC on Friday.
Shenzhou-9 Return:
The mission achieved all of its main goals, including the milestone of an automated crew docking, followed by a manual docking midway through the mission.
The crew, consisting of Jing Haipeng, Liu Wang and Liu Yang, enjoyed a normal ride to orbit via their Long March 2F/G launch vehicle, following lift-off from the Jiuquan Satellite Launch Center, prior to docking with unmanned space module Tiangong-1 – a vehicle that was launched back on September 29, 2011.
After the June 18 docking, the crew adapted to the work aboard Tiangong-1, before carrying out their routine medical examinations during the mission, including measuring blood pressure, body temperature and body weight – communicated to medical support specialist on the ground.
Other space experiments included microbiological testes and evaluation of the human biological rhythms, as well as physiological studies and experiments in the microgravity environment.
On June 22, the taikonauts manually changed the attitude control for the joined spacecraft – a first for the Chinese – five days after the historical docking in orbit. The control system on Tiangong-1 was turned off by Liu Wang, prior to testing three different kinds of positioning, with Shenzhou-9 taking charge of the flight.
This was followed by a mission milestone, as the Shenzhou-9 undocked for the manual docking test.
For this event on June 23, the Shenzhou-9 backed to a distance of 400 meters, prior to closing back in to 140 meters, at which point the two vehicles maintained their distance.
The ground then gave their approval for the manual approach, controlled by Liu Wang, from the 140 meter point, prior to a short hold point at 30 meters. Closing in at 0.4 meters per second, the successful completion of the manual docking took place at around 4:50 UTC.
Shenzhou is based on the Russian Soyuz-TM spacecraft and can carry up to three astronauts inside its Re-Entry Module. Like on the Soyuz manned spacecraft, on re-entry, the orbital and service modules are separated and discarded, allowing the re-entry module makes its descent through the atmosphere.
The total mass of the spacecraft was 8,082 kg, with a length of 9.25 meters, diameter of 2.80 meters and a 17 meter span.
The Orbital Module has a length of 2.80 meters, a mass of 1,500 kg and a diameter of 2.25 meters, equipped with two solar panels for power generation (0.5 W) and each panel is 2.0 meters by 3.4 meters. This module sports a propulsion system comprised of 16 small thrusters, in four groups.
The Re-entry Module has a length of 2.50 meters, a mass of 3,240 kg and a diameter of 2.52 meters. This module is equipped with a heat shield with a mass of 450 kg.
The Service Module has a length of 3.05 meters, a mass of 3.000 kg and a maximum diameter of 2.80 meters. Is equipped with two solar panels for power generation (1.5 W) and each panel is 2.0 meters by 7.0 meters.
This module was equipped with the Shenzhou main propulsion system that consists of four high-thrust main engines and 24 smaller-thrust control engines, as well as four 230-litre propellant tanks containing a total of 1,000kg N2O4/MMH liquid propellant.
The four main engines (2.5kN) are located at the base of the spacecraft's Service Module. The spacecraft also used eight (in four pairs) 150N pitch and yaw thrust vectors, eight (in four pairs) 5N pitch and yaw thrust vectors and eight (in four pairs) 5N roll / translation thrust vectors.
Following a nominal return to Earth – at the primary landing site – the Shenzhou-9 touched down in daylight in what appeared to be a rather bumpy landing. However, the three member crew were all reported to be in good health, after landing crewed arrived at the spacecraft.
The next mission, Shenzhou-10, is expected to involve a three week long docked mission with Tiangong-1.
(Images via CCTV and ChinaNews.cn)
