China's launches X-ray pulsar navigation satellite and first commercial science probe

2016.11 10

China carried out its 17th orbital launch of 2016 early on Thursday, sending the world’s first X-ray pulsar navigation satellite into orbit, along with four other small satellites.

The satellites were carried into a 500km, 97 degree Sun-synchronous orbit by the second launch of a solid-fuelled Long March 11, taking place at 07:42 local time (23:42 UTC Wednesday) from the Jiuquan satellite Launch Centre.
The launch was the first from Jiuquan in the Gobi Desert since Shenzhou-11 in mid-October, and will be followed by another launch early on Friday local time.

The 240kg X-ray pulsar navigation XPNAV-1 satellite is charged with conducting the world's first test of the possibilities of using the regular emission of X-ray signals from pulsars for spacecraft navigation.

Above: A rendering of China's XPNAV-1 satellite (CAST).

The spacecraft will attempt to triangulate its position relative to the Sun using the highly regular emissions from pulsars.

If successful, the technology could dramatically cut the reliance of craft in deep space on the huge ground-based communications and increase their autonomy.

Xiaoxiang-1 (XX-1), developed by the private, Changsha-based Spacety Aerospace Co, is a 6-unit cubesat with a mass of 7.49kg designed as a pathfinder for a commercial ‘Mini-Hubble’ optical telescope to be launched next year.

SPACETY develops microsatellites for scientific experiments and technology validation. Ren Weijia, an engineer with the company and formerly with the Chinese Academy of Sciences, told gbtimes that from the very beginning, SPACETY planned to make a commercial astronomical telescope but found the project would be very difficult to finish in one move.
“So we first designed a satellite for technical verification, specifically to test core techniques for satellite platforms and optical image stabilisation technology. We also have some orders from customers, all of which have been combined into the XX-1 plan.”
To get their payload in orbit, SPACETY first applied to the China Academy of Launch Vehicle Technology (CALT) for a place on their Long March 11 rocket, which can be used for commercial purposes. Together they applied for clearance and support from the State Administration of Science, Technology and Industry for National Defence (SASTIND), which oversees China’s space activities.


— ChinaSpaceflight (@cnspaceflight) November 10, 2016

SPACETY also worked with a range of institutes in China, as well as companies in Denmark, Spain and South Africa.
Xiaoxiang-1 is the Chinese first commercial satellite for science experiments and is expected to operate in orbit for 6 months to 1 year.
Ren had previously worked on China’s Hard X-ray Modulation Telescope (HXMT) space science missionthat is expected to launch early next year.

China outlines its long-term vision for space science

— SpaceRef China (@ChinaInSpace) February 17, 2016 states that the three other payloads on the Long March 11 ride were Lishui-1 small commercial remote sensing satellites, developed by the Zhejiang LiTong Electronic Technology Co., Ltd.

Another payload remained attached to the upper stage for a short stay in orbit.

XPNAV-1 was developed by the China Academy of Space Technology (CAST) under the China Aerospace Science and Technology Corporation (CASC), the main contractor for China’s space programme, which also owns CALT.

239 and counting

Thursday's Long March 11 launch was the 239th for the Long March family of rockets, starting with the launch of China's first satellite, Dong Fang Hong-1, on a Long March 1 rocket on April 24, 1970.

The previous launch was the debut of the Long March 5, China's larger ever rocket, which will allow the country to build aspace station and launchdeep space missions.