China’s Long March 2D places 2 SuperView-1 satellites into wrong orbit
China’s Long March 2D rocket lifted off at 11:23 a.m. China Standard Time (03:23 GMT) on Dec. 28, 2016, from the Taiyuan Satellite Launch Center in Shanxi Province. The booster carried with it two SuperView-1 satellites designed for Earth observation purposes.
While Chinese media reported the launch a success, according to Spaceflight101, orbital data showed the two main payloads did not reach their intended orbit and various flight sequence events did not match up with pre-launch predictions. What orbit the satellites are currently in is not known officially, but a user on Twitter who is tracking a CubeSat which flew piggyback on the flight reported that it was in a 323 by 137 mile (520 by 220 kilometer) orbit.
The mission’s goal was to send the duo of satellites into a Sun-synchronous orbit (SSO) at an altitude of about 310 miles (500 kilometers). From this orbit, they were to acquire high-resolution imagery of the Earth for civilian purposes.
As usual, Chinese media have not revealed the details about pre-launch activities and about the launch itself. Moreover, limited information was available about the mission timeline.
Preparations for the mission entered its final stage with the arrival of both satellites at Taiyuan in November. It was a busy month for the launch center engineers as they conducted initial checkouts and tests of the spacecraft and began the assembly of the Long March 2D launcher.
After liftoff, the rocket began its brief vertical climb before turning south across mainland China, toward the South China Sea. During the initial phase of the flight, the rocket was powered by the main stage’s YF-21C engine delivering 2,962 kilonewtons of thrust. This stage was detached about three minutes after liftoff.
Afterward, the second stage’s YF-24C cluster engine was ignited, marking the start of a seven-minute ride into orbit. This phase should have concluded approximately 10 minutes after liftoff minutes when the spacecraft were deployed into space.
The mission’s passengers, named SuperView-1 01 and SuperView-1 02 (also known as GaoJing-1 01 and GaoJing-1 02), are the first two out of four satellites of the first generation of the SuperView constellation. They are both identical spacecraft, built by the China Academy of Space Technology (CAST). The satellites are based on the CAST3000B platform and are fitted with two deployable solar arrays.
If the off-target orbital insertion can be rectified, the pair of SuperView-1 spacecraft will be operated by the Beijing Space View Technology Co., Ltd. They will provide imagery with 1.64-foot (0.5-meter) panchromatic resolution and 6.56-foot (2-meter) multispectral (blue, green, red, near-infrared) resolution.
The satellites are designed to work in multiple collection modes including long strip, multiple strips collect, multiple-point targets collect, and stereo imaging. They are expected to deliver highly detailed imagery for precise map creation, change detection, and in-depth image analysis.
Both spacecraft feature a data collection capability of two terabytes of storage on board and, if in the proper orbit, are able to obtain images covering 270,300 square miles (700,000 square kilometers) across the globe per day.
“The multiple strips collect mode will realize high-resolution surveying and mapping with large swath width, and the stereo imaging mode will bring large opportunities for DEM (digital elevation model) production,” the SuperView-1 brochure states.
The next two SuperView-1 satellites, namely SuperView-1 03 and SuperView-1 04, are scheduled to be launched into space in mid-2017. They will be deployed into the same intended orbit and will have identical capabilities as the two launched today.
Accordingly, there will be four 1.64-feet resolution SuperView-1 satellites in orbit, phased 90 degrees from each other on the same orbit to collect imagery for clientele across the world, assuming the two launched today can be moved to the correct orbit.
The two-unit CubeSat known as Bayi Kepu Weixing 1 (BY70-1) that piggybacked the mission has a mass of about 4.4 pounds (2 kilograms). This CAST-built tiny satellite is an amateur radio technology demonstrator designed for educational purposes. It will provide telecommand, telemetry, and FM repeater functions.
The Long March 2D is a two-stage rocket developed by the Shanghai Academy of Spaceflight Technology. It is mainly used to launch satellites into low-Earth orbit (LEO). The 135 feet (41.15 meters) tall booster can launch payloads of up to 3.5 metric tons to LEO and has an SSO capability of up to 1.3 metric tons.
The rocket was launched for the first time on Aug. 9, 1992, from the Jiuquan Satellite Launch Center, orbiting the Fanhui Shei Weixing FSW-2-1 recoverable satellite.
Wednesday’s flight was the 244th flight of the Long March rocket series. It was also the ninth orbital launch from the Jiuquan Satellite Launch Center in 2016 and the 21st mission conducted by China this year.
China plans one more orbital launch before year’s end. On Dec. 30, a Long March 3B rocket will lift off from the Xichang Satellite Launch Center, carrying the TJS 2 communications satellite for China National Space Administration.
Video courtesy of CCTV+
Tomasz Nowakowski is the owner of Astro Watch, one of the premier astronomy and science-related blogs on the internet. Nowakowski reached out to SpaceFlight Insider in an effort to have the two space-related websites collaborate. Nowakowski's generous offer was gratefully received with the two organizations now working to better relay important developments as they pertain to space exploration.