A group of polar-orbiting satellites flying in formation (known as a constellation), and following one another in orbit, thus monitoring a single swathe of the Earth with a sequence of different instruments at essentially the same time. The orbit has a nominal altitude of 705 km, an inclination of 98°, and crosses the Equator at c.13:30 UT (hence ‘Afternoon’). The interval between the leading and trailing satellites is maintained to be less than 15 minutes. Currently, the satellites (in order) are: Aqua, Cloudsat, Calipso, Parasol, and Aura. The Orbiting Carbon Observatory (OCO) will be inserted ahead of Aqua on launch, which is expected to be in 2008.
Subjects: Meteorology and Climatology.