Today China launched first pair of new commercial remote sensing satellites – Gaojing-1-1 and Gaojing-1-2. First pair will be followed by another two with planned launch in 2017.
Mission was covering delivering pair of the satellites to SSO orbit with altitude of 500 km. Both should be placed on same position of 180° and operate for at least 5 years. Launch was performed at 03:23 UTC from LC9 launch pad at Taiyuan Satellite Launch Center. In spite of delivering two Gaojing satellites, Long March 2D also delivered piggyback payload: amateur radio and educational satellite BY-70 was also delivered today. Sized as CubeSat-2U, BY-70 is equipped with deployable solar arrays and 3 axis attitude control. It will operate from 530 km circular SSO orbit for at least 180 days.
First problems were spotted already in early phase of the mission – according some sources (mainly on Nasaspaceflight forum and on Chinaspaceflight twitter profile) first stage of Long March 2D separated 7 seconds late. Cut off of the propulsion of second stage was also late for approximately 10 s. About 10:00 UTC official sources in China confirmed, that mission was only partial success – only BY-70 reported its condition correctly from 550 km x 220 km orbit. Satellites were deployed for sure – it was confirmed by USSTRATCOM, that four objects were spotted:
- 2016-083A / 41907 w 214 x 524 km x 97.58 °
- 2016-083B / 41908 w 213 x 524 km x 97,59 °
- 2016-083C / 41909 w 212 x 524 km x 97,59 °
- 2016-083D / 41910 w 216 x 524 km x 97.589 °
According to some sources Gaojing satellites were deployed too early and they are not positioned on correct orbit. Operator of Gaojing still did not presented official statement on the condition of both satellites.
Gaojing are also known also as SuperView-1 and they are civilian remote sensing satellites operated by the Siwei Star Co. Ltd., which is owned by China Siwei Surveying and Mapping Technology Co. Ltd. This company is subsidiary of China Aerospace and Technology Corporation (CASC), one of the main space state corporations in China. Data collected from satellites will be widely available for international customers – their distribution will be possible thanks to Beijing Space View Technology Co., Ltd. company, which will be ultimate distributor. Plans for future are covering creating constellation of 16 optical imaging satellites with comparable imaging devices, four additional satellites with better resolution, four VHR X band radar imaging satellites and number of micro video and hyperspectral satellites. Constellation should be ready in 2022.
Optical imaging Gaojing-1 satellites were based on CAST3000B satellite bus by China Academy of Space Technology. It offers payload mass of 380 kg with bus weight depending on configuration and varying from 300 kg to 400 kg. CAST3000B is equipped with two deployable solar arrays providing peak power of 1148 W and onboard batteries. Attitude control system is 3-axis with hydrazine fueled thrusters. Main payload of Gaojing-1 is imaging device operating with 0.5 m resolution in panchromatic mode and 2 m in multispectral mode. Swath width is 12 km; device is able to deliver on single picture image of area of 4200 square kilometers (60 km x 70 km).
Long March 2D was designed in the late eighties by Shanghai Academy of Spaceflight Technology. It has been in service since first mission in 1992. It is based on two liquid fueled stages; first stage is equipped with four YF-21C engines (fueled with N2O4 and UDMH) with thrust at 2961.6 kN. It is long for 27.91 m with diameter at 3.35 m and weight at 182000 kg. Second stage is powered by one YF-24C engine consisted of one YF-22C as main engine and four YF-23C for stabilization. Thrust of YF-22C is at 742.04 kN and for single stabilizing engine is at 47.1 kN. Second stage has following dimensions: length at 10.9 m with diameter at 3.35 m and weight at 52700 kg. Rocket offers SSO payload at 1300 kg and for LEO orbit – 3500 kg.