Nano-Satellites are becoming more popular because of the commercial efficacy, cost-effectiveness, mass production capability, use of commercially available components, lowest realization time and versatile utility ranging from scientific/ commercial/ experimental and/or innovative payloads/ instruments, technology demonstrators, flight experiments, to that of a constellation / swarm of nanosatellites and having formation flights with higher frequency of revisits. These satellites mass ranges from 1 to 10kg and size in multiples of cube of size 10 cm.

Low earth orbiting satellite altitude varies from 160 km to about 1000 km. The orbit type will be polar orbits with certain inclination. The thermal environment for the spacecraft depends on the orbit. The environment (space, the sun, earth, atmosphere around moving satellite) decides the thermal loads and other detrimental effects (erosion, unbalanced forces, etc.). A satellite in orbit experiences solar, earthshine and albedo (reflected solar) loads. On the other hand, same satellite gets exposed to the cold space (~0 K). These effects in combination can expose satellite and its subsystems to a wide range of temperature, which has to be narrowed down to a desirable range. Effect of type of orbit poses different challenge to the satellites. The total power generation will be of the order of about 50 W out of which nearly 50 to 80 % is dissipated as thermal power and thermal management for this class of spacecraft is a major challenge thanks to the limited availability of resources.

This study aims to numerically predict the effect of change in orbit on environmental thermal loads and subsystem temperatures of a typical Nano-satellite for different orbital parameters. A typical thermal design is discussed for these classes of satellites.