Features

Image from TERRA
2021 Disasters: A Look Back
Thu, 30 Dec 2021 13:00 EST

In 2021, Hurricane Ida left over 1 million people without power, tornadoes tore across the American Midwest, volcanoes forced people to evacuate their homes, wildfires covered the American West and unusual flooding wreaked havoc on Central Europe.

Image from TERRA
OpenET: A Satellite-Based Water Data Resource
Thu, 21 Oct 2021 10:00 EDT

Instruments, like this flux tower, are used by scientists to verify the accuracy of the data available in OpenET, a powerful new web-based platform that puts Earth science data about water use by crops and other vegetation into the hands of farmers and water managers.

Image from TERRA
NASA Smoke Signals for Air Quality
Thu, 07 Oct 2021 13:00 EDT

The U.S. Forest Service now has a powerful way to view near-real time fire detection from NASA satellite data that they can include in their hourly air quality forecasts.

Home › About Terra

About Terra

Approximately the size of a small school bus, the Terra satellite carries five instruments that take coincident measurements of the Earth system:

Terra is in a circular sun-synchronous polar orbit that takes it from north to south (on the daylight side of the Earth) every 99 minutes.

Spacecraft Quick Facts:
  • Launch Date: December 18,1999
  • Size: the spacecraft bus is 6.8 m long and 3.5 m across.
  • Weight: 5,190 kg (11,442 lbs.) at launch.

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Orbit Quick Facts: 
  • Altitude: 705 kilometers (438 miles) above Earth’s surface
  • Inclination: 98.5 degrees
  • Period: 99 minutes (14 complete orbits per day)
  • Ground track repeat: 16 days
  • Equatorial crossing: 10:30 a.m., descending mode

Terra Status:

  • Operating instruments: ASTER, CERES, MODIS, MISR, and MOPITT are operating well.  ASTER Short Wave Infrared (SWIR) data is unavailable.
  • Current systems issues: None.
  • Processed Terra data are available through several NASA data centers.
  • Current life expectancy: Terra  has far exceeded its design life and has a strong chance of operating successfully into the early 2020s. Terra began drifting in February of 2020. Read more about Terra’s drifting or see key dates below.

Key dates of Drift

  • Exceed 10:30 MLT (+/- 1 min) – April 2021*
  • Exceed 10:15 MLT – October 2022*
  • Constellation Exit – October 2022*
  • Exceed 9:00 MLT – December 2025*

Passivation dates are not yet determined, but passivation is expected to take place due to signal to noise limits from lower solar zenith angles, limited battery power from changing solar angle on the solar panels, or programmatic funding limits.

*Dates are subject to change.