Spacecraft for this lunar mission is a cuboid of approximately 1.5 m side, weighing about 675 kg at lunar orbit. It is a 3-axis stabilized spacecraft. A single canted solar array will provide the required power during all phases of the mission. The panel generates about 750 W of average power and will be supported by a Lithium ion (Li-Ion) battery during eclipse operations. The Chandrayaan-1 deployable solar array consisting of a single panel and yoke is stowed on the deck of the spacecraft. After deployment, the solar panel plane is canted by 30 to the spacecraft pitch axis.
The spacecraft uses an X-band, 0.7 m diameter parabolic dish antenna for payload data transmission. The antenna is required to track the earth station, when the spacecraft is in lunar orbit.
The spacecraft uses a bipropellant integrated propulsion system to carry it to the lunar orbit as well as to provide orbit ant attitude maintenance, while at the Moon. The propulsion system will carry required propellant for a mission life of 2 years, with adequate margin. The Telemetry, Tracking & Command (TTC) communication will be in the S-band and the scientific payload data transmission will be in –band.
The spacecraft has three Solid State Recorders (SSRs) on board to record data from carious payloads. SSR-1 (TMC/HySI/Mini-SAR) will store science payload data and has capability of storing 32Gb data; SSR-2 will store science payload data (HEX, C1XS, RADOM, LLRI, SIR-2, SARA and MIP) along with spacecraft attitude information (gyro and star sensor), satellite house keeping data and other auxiliary data. SSR-2 is designed
to collect and store data for 7 non-visible orbits w.r.t IDSN Bangalore. The storing capacity of SSR-2 is 8Gb. M3 payload has an independent SSR with 10Gb capacity.