Double Star 1 (also known as Tan Ce 1, and TC 1) is a Sino-European (CSNA-ESA)
satellite that was launched by a Long March 2C/SM rocket from Xichang Satellite Launch Center
in the Sichuan province of China (PRC) at 19:06 UT on 29 December 2003. The 330 kg, 260 W
satellite is cylindrical, with a diameter of 2.1 m, a height of 1.4 m, and spins at a rate
of 15 rpm. It carries eight instruments to probe Earth's magnetosphere, five from ESA and
three from CNSA. (The ESA instruments are legacies from ESA's Cluster mission.) The data
from all instruments will be stored on-board and dumped over three grounds stations:
Shanghai and Beijing in China, and Villafranca in Spain. There will be coordination
between the Cluster and Double Star missions.