NASA’s Orbiting Carbon Observatory-2 Set to Join the A-Train

NASA’s first satellite devoted to measuring atmospheric CO2 is ready to launch. The Orbiting Carbon Observatory-2 will join a constellation of five other satellites gathering information about Earth systems with unprecedented resolution and coverage.


Launching on July 1, the Orbiting Carbon Observatory-2 will gather critical information about sources and sinks of CO2 in the atmosphere. Image Credit: NASA.

Launched on July 2, the Orbiting Carbon Observatory-2 will gather critical information about sources and sinks of CO2 in the atmosphere. Image Credit: NASA.



Update: OCO-2 was launched successfully on Wednesday, July 2. A technical problem caused a 24-hour delay.

It’s called the A-Train (short for “Afternoon Train”) — five Earth observing satellites traveling on the same path within seconds of each other, circling the planet every 99 minutes, and crossing the equator at 1:36 p.m. local time. On July 1, a new satellite will take its place at the head of the A-Train: NASA’s Orbiting Carbon Observatory-2 (OCO-2), on a mission to help scientists better understand the planet’s carbon cycle. (See update, below.)

“Carbon dioxide in the atmosphere plays a critical role in our planet’s energy balance,” Michael Freilich, director of NASA’s Earth Science Division, said in a NASA statement. “With the OCO-2 mission, NASA will be contributing an important new source of global observations to the scientific challenge of better understanding our Earth and its future.”



OCO-2 will be NASA’s first spacecraft devoted to measuring atmospheric carbon dioxide (CO2). (A nearly identical satellite was lost in a rocket launch failure in 2009.) The scientific instrument onboard consists of three high-resolution grating spectrometers, used to measure the intensity of sunlight reflected through the atmosphere. Analyzing these fluctuations allows for extremely precise measurements of CO2.

“The instrument recognizes 3048 colors within three narrow ranges of near infrared light,” says David Crisp, a senior research scientist at the Jet Propulsion Laboratory and leader of the mission’s science team. “For comparison, most digital cameras register only three colors over the visible part of the spectrum.”

The Delta II rocket carrying OCO-2 into orbit is set to launch at 5:56 a.m. EDT (2:56 a.m. PDT) from Vandenberg Air Force Base in California. You can watch the launch live online at NASA TV.

The A-Train constellation of Earth observation satellites. Image Credit: NASA.

The A-Train constellation of Earth observation satellites. Image Credit: NASA.