Chinese Long March 11 launches 5 Earth observation satellites
Using a Long March 11 rocket, China orbited five satellites designed for Earth-observing purposes. Liftoff took place at 12:42 a.m. EDT (4:42 GMT) April 26, 2018 from Launch Area 4 at the Jiuquan Satellite Launch Centre in the county’s Gansu Province.
The mission was initially scheduled for late March, however it was later delayed one month. Chinese media have not disclosed the reason for the postponement. Moreover, very little is known about the launch and orbital flight as Beijing typically keeps the details of its missions under wraps.
What is known is that the booster completed a brief vertical ascent after liftoff and then started heading south across mainland China in order to fly over Myanmar toward the Bay of Bengal. The remaining part of the flight’s timeline is uncertain. China only revealed that the satellites are planned to be inserted into a Sun-synchronous orbit (SSO).
The five spacecraft are for the Zhuhai-1 Earth-observation constellation. They include one high-resolution video satellite (OVS), designated OVS 2A, and four hyperspectral satellites (OHS)—OHS 2A, 2B, 2C and 2D.
Zhuhai-1 satellites are operated by the China-based company Zhuhai Orbita Control Engineering Ltd. Each spacecraft in the series is equipped in a high-resolution video system capable of capturing 20 frames per second and reaching a ground resolution of 6.5 feet (1.98 meters).
The Xinhua state-run press agency reported that the Zhuhai-1 constellation “will provide data services for areas including agriculture, land and water resources, environmental protection and transport.”
Manufactured by the China Academy of Launch Vehicle Technology (CALT), the Long March 11 booster that was used for the April 26 launch is a small, solid-fueled quick-reaction launch vehicle. It utilizes the most powerful solid-rocket motor that China currently manufactures and is mainly used for launching micro-satellites.
Measuring 68 feet (20.8 meters) tall and some 6.6 feet (2 meters) in diameter, the Long March 11 is capable of sending up to 1,500 pounds (680 kilograms) to low-Earth orbit and 770 pounds (350 kilograms) to SSO. The booster uses three solid-fueled stages with an auxiliary liquid-fueled upper module for precise insertion capability. It is launched from a mobile launch platform.
China’s Long March 11 is the next in a line of launch vehicles being inaugurated by the country as part of the beginning of a major transition in rocket technology. Beijing is switching from a toxic propellant combination to what the country has described as environmentally-friendly propellants for medium- and heavy-lift rockets and solid propellant for light-lift vehicles.
This launch marked the fourth by a Long March 11 booster and the 272nd flight in the Long March rocket family overall. The first orbital launch of a Long March 11 took place on Sept. 24, 2015, when it sent three Tianwang CubeSats and the Pujiang 1 micro-satellite into space. So far in 2018, the country has launched 12 orbital-class rockets.
China’s next orbital launch is currently scheduled for May 2, when a Long March 4C booster will lift off from the Taiyuan Satellite Launch Center in order to orbit the Gaofen 5 Earth-observing satellite.
Video courtesy of CGTN
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