This paper describes the Topsat satellite programme, focussing on the key technical, operational and commercial aspects of the mission. Topsat is designed to demonstrate the capabilities of small satellites for classically high value remote sensing missions. Topsat is a 120kg, sun-synchronous satellite, designed to provide 2.5m resolution imagery direct to users in the locale of the imaged area. It is an end-to-end mission encompassing development, build, launch, operation and exploitation. Its objectives are to demonstrate the capability to cost performance available from small satellites and the utility of direct tasking and reception of remotely sensed imagery. It is expected that Topsat will be exploited both through its imagery and through the demonstration of affordability of constellations and individually owned assets. The paper provides an overview of the mission and an update to the status of the mission as of July 2002.
This paper explores the relationships between optical imagery performance metrics, and the requirements they place on the attitude control, and orbital knowledge, of a small, low cost, optical remote sensing satellite. These relationships are illuminated by the very real decisions and trade offs encountered in the design and development of the Topsat satellite. Topsat is a small, sun-synchronous satellite, designed to provide 2.5m resolution panchromatic imagery and 5m multispectral imagery in the three visible wavebands.