Equator-S was a low-cost mission, launched with the intention to study the Earth's magnetosphere around the equator at heights lower than 67,000 km.[1] It was located in a near-equatorial orbit, which gave Equator-S the ability to make unique observations about the interaction between the magnetosphere and interplanetary space.[4] Equator-S had a very high spin rate and was launched on an Ariane 4 rocket on 2 December 1997.[1]
The mission ended earlier than expected, having initially been intended to have a lifetime of two years. The mission was terminated on 1 May 1998 after the failure of the onboard processor system.[1]
Payloads are separated by bullets ( · ), launches by pipes ( | ). Crewed flights are indicated in underline. Uncatalogued launch failures are listed in italics. Payloads deployed from other spacecraft are denoted in (brackets).