Terra

About this satellite

Terra is NASA's flagship Earth-observing satellite, launched in December 1999. Its five instruments measure the atmosphere, land, oceans and energy balance to track how the planet's climate is changing.

Operator

NASA

Owner

United States

Purpose

Climate and Earth-system research

Launched

18 December 1999

Launch vehicle

Atlas IIAS

Status

Extended mission

International designator

1999-068A

Altitude

688 km to 691 km (perigee to apogee)

Orbital period

98.5 minutes (14.6 orbits a day)

Inclination

97.9°

Mass

4,864 kg at launch

Orbit and catalogue data: CelesTrak SATCAT, updated 2026-10-18.

• NASA: Terra
• Wikipedia: Terra (satellite)