UPDATE ON ASTER VNIR: After investigation and monitoring of platform battery status, the Terra Flight Operations Team (FOT) determined thatthere was sufficient power to resume imaging with ASTER’s VNIR instrument. The FOT will continue to monitor the power usage, but as a result, ASTER once again began collecting VNIR data on January 17, 2025. To view recent imagery, visit this linked Land Processes Distributed Active Archive Center webpage.
Previous Battery Update: On November 28th, 2024 at 14:20 UTC, one of Terra’s power-transmitting shunt units failed. A response team reviewed Terra’s status, and discussed potential impacts and options. Consequently, the team changed the battery charge rate and reduced spacecraft power demands by placing the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument into Safe Mode. As a result, ASTER data are not currently being collected. All other instruments continue uninterrupted. The engineering team will continue to closely monitor Terra’s power output and provide future updates on ASTER’s status.
Click the banner above for more information about this monumental landmark for the Terra Mission!
Terra: The EOS Flagship
Terra explores the connections between Earth’s atmosphere, land, snow and ice, ocean, and energy balance to understand Earth’s climate and to map the impact of human activity and natural disasters on communities and ecosystems
Connecting Earth’s Systems with Terra’s Observations
Examples of each instrument’s capabilities (clockwise): land composition (ASTER), reflected energy (CERES), aerosols (MISR), vegetation snow and ice (MODIS), carbon monoxide (MOPITT)
Important Terra Updates and Information
Direct Broadcast Update (November 2024): Terra has not been transmitting Direct Broadcast since May 11, 2024, due to a solar array power generation issue limiting our ability to continue all science and provide Direct Broadcast continuously. Unfortunately, there are no plans to resume Terra Direct Broadcast.
November 2024 Data Impacts: Terra successfully completed a multi-day special maneuver to allow for calibration of the MODIS instrument’s diffuser. Data collection from all Terra instruments were briefly interrupted during this process (see specific dates and times below).
Day 1 (11/12/24) – 16:41z – 22:22z Day 2 (11/13/24) – 12:24z – 21:25z Day 3 (11/14/24) – 13:01z – 22:04z Day 4 (11/15/24) – 12:07z – 20:38z
A programmatic change in the Terra mission prompted the flight operation staffing to go from 24 hours a day, 7 days a week to 12 hours a day, 7 days a week, with limited operational response when staff are not on site. For more information, see below.
The Terra and Aqua Flight Operation Team (FOT) transitioned fully to Light-Out-Operations (LOOps) on July 7th 2023 at 6am EDT, following successful testing and Ops Readiness Review.
In the LOOps configuration there will not be an on-console engineer working the 12-hour night shift (6pm-6am), but instead system support engineers will be on call during lights out period to respond to red limit alarms as needed.
FOT will no longer attempt to fill science data gaps via Solid State Recorder replays so additional data losses and larger data gaps are expected, though estimated data capture is expected to remain above mission data capture guideline of 95%.
Terra data users have expressed the need for weekly updates on Terra’s equator crossing time (in Mean Local Time), as well as orbital altitude. Starting this month, we’ll be adding this information to the Terra homepage and updating it weekly using data provided by the Operations Team. Move your cursor over the chart below to view both Terra’s Mean Local Equator Crossing Time in UTC and orbital altitude for each month through 2026.
Update on Terra’s New Orbit: Since 2020, Terra has been drifting to an earlier equator crossing time, and in October 2022 was lowered by ~5km in altitude. These changes in orbit did not reduce the data quality of Terra products, and only created minor changes to orbital repeat time and swath width (for some instruments). See Terra’s New Orbit for more information.
This year has been a busy one for Terra, with our 25th Anniversary just around the corner! (Learn more and RSVP here!) In the season of thanksgiving, Terra is especially grateful for the following: Thanks again for all of your support over the years! Wishing you all a relaxing holiday full of food and friends!
You may have heard about the upcoming full solar eclipse, happening this upcoming April 8th, 2024 — but did you know Terra will have one of the “best seats in the house” for viewing this rare celestial experience?! In the United States, the center “totality” shadow of the eclipse will pass from south to north …
Before we kick off an exciting year — full of celebrating Terra’s upcoming 25th Anniversary! — let’s take a moment to look back at the top-viewed monthly Earth Observatory stories featuring the Terra mission from 2023! Click the linked month in each banner to jump down to a brief article summary and image thumbnail. Want …
After more than 20 years orbiting at 705 km above Earth’s surface and routinely crossing the equator at approximately the same time every day, Terra is now drifting. With no maneuvers planned to sustain Terra’s altitude and crossing time, Terra will slowly get closer and closer to Earth – crossing the equator earlier and earlier as time passes. However, despite impacts to some of Terra’s nearly 100 data products, Terra’s five sensors continue to collect meaningful scientific data, producing one of the longest continuous climate data records collected by a satellite. Read more…
Terra’s five sensors help us understand out changing planet and provide critical data used in applications from food security, volcanic monitoring, wildfire safety, public health, and climate modeling. Terra’s twenty years of data continue to contribute to how we understand Earth and how we respond when disasters strike.
Terra’s suite of instruments allows us to understand our world well beyond what we knew twenty years ago, when Terra launched. In those twenty years, new applications and contributions to science have been made possible.
There is no question that technology has changed. But, at the same time that our lives on Earth were being shaped by our access to technology, 705 kilometers above us, a satellite was changing how we understood our planet.
For 20 years, Terra, the flagship Earth observing satellite, has chronicled changes on Earth. Designed and built in the 1980s and 90s, NASA and Lockheed Martin engineers set out to build a satellite that could take simultaneous measurements of Earth’s atmosphere, land, and water. Its mission – to understand how Earth is changing and to identify the consequences for life on Earth. Season after season, Terra data continues to help us understand how the evolving systems of our planet affect our lives – and how we can use that data to benefit society. Read more and find resources from our anniversary events, Terra 20 Events
Update on Terra’s New Orbit: Since 2020, Terra has been drifting to an earlier equator crossing time, and in October 2022 was lowered by ~5km in altitude. These changes in orbit did not reduce the data quality of Terra products, and only created minor changes to orbital repeat time and swath width (for some instruments). See Terra’s New Orbit for more information.