Starshine 3 consists of over 1,500 hand-polished mirrors, 31 retro-reflectors and seven clusters of solar cells powering an amateur radio transmitter. It will be deployed into a 500 km (270 nmi) high orbit at an inclination of 67 degrees. Flashes from the satellite will occur every two seconds. They will be visible just after sunset and just before sunrise as far north as Point Barrow, Alaska and as far south as McMurdo Station, Antarctica. The Starshine Program involves participation from students in kindergarten through high school. This will be the first time that students from Alaska, and nations at high latitudes, can participate in the project due to the higher orbital inclination.

The Starshine 3 spacecraft is a hollow aluminum sphere, nearly a meter in diameter (37 inches), that weighs 90 kilograms (197 lbm). The solar cells mentioned above power a radio communication system built by Cynetics Corporation and the South Dakota School of Mines and Technology. The system's transmitter will send out a beacon signal every one to two minutes at a frequency of 145.825 Megahertz to amateur radio operators, or "hams," all over the world. The hams will relay the output of the solar cells, so students can determine how the spin rate of the satellite slows down during the mission. Eddy currents in the alumuminum shell, generated by the satellite's passage through the earth's magnetic field, will brake the satellite's spin at a rate that is hard to calculate, so we'll measure that spin rate throughout the mission.