Celebrating Terra's 20th Anniversary

Test your trivia knowledge of the Terra satellite and be entered to win a prize during AGU.

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What instrument measures carbon monoxide, a precursor to carbon dioxide and ozone, and also a gas that lengthens methane’s lifetime?

MOPITT - Measures tropospheric carbon monoxide (CO). CO is mostly produced by incomplete fuel combustion, biomass burning, and oxidation of methane and other hydrocarbons.


What instrument can be pointed to collect high resolution data and is used as part of the Urgent Request Protocol to monitor natural disasters and active volcanoes?

ASTER - The Advanced Spaceborne Thermal Emission and Reflection Radiometer obtains high-resolution (15 to 90 square meters per pixel) images of the Earth in 14 different wavelengths of the electromagnetic spectrum, ranging from visible to thermal infrared light. Scientists use ASTER data to create detailed maps of land surface temperature, emissivity, reflectance, and elevation.


How did Terra get it's name?

Sasha Jones of Brentwood, MO – a high school student whose essay was chosen in a contest. An excerpt: “The woman I believe this satellite should be named after is the most beautiful woman ever. .... She is our history, all of it. She is our present, she allows us to be. She is our future and we must care for her, as she is the most caring and beautiful woman in the universe. She will be the mission of this EOS AM-l, and we should name it after her, in honor of her. She is Terra: Mother Earth."


What technology that is commonly used by people today debuted the same year Terra launched, 1999?



What instrument on Terra is used to find active wildfires?

MODIS - With its sweeping 2,330-km-wide viewing swath, MODIS sees every point on our world every 1-2 days in 36 discrete spectral bands. Consequently, MODIS tracks a wider array of the earth’s vital signs than any other Terra sensor.


How many instruments are on board Terra?

Approximately the size of a small school bus, the Terra satellite carries five instruments that take coincident measurements of the Earth system: ASTER, CERES, MISR, MODIS, MOPITT. Because all five instruments are on the same satellite making simultaneous observations, scientists are able to compare different aspects of Earth’s characteristics over time.


How many years was Terra designed to operate?

Terra's mission was slated for 6 years, but has far exceeded its design life and has a strong chance of operating successfully into the early 2020s– more than 20 years.


How many minutes does it take for Terra to complete an orbit?

99 minutes. Terra images the whole Earth every 1 – 2 day.


What question was Terra designed to answer?

How is Earth changing and what are the consequences for life on Earth? In December 1999, NASA launched the Terra satellite as the flagship mission of the Earth Observing System to answer these questions. Terra carries instruments that observe Earth’s atmosphere, ocean, land, snow and ice, and energy budget. Taken together, these observations provide unique insight into how the Earth system works and how it is changing. Terra observations reveal humanity’s impact on the planet and provide crucial data about natural hazards like fire and volcanoes.