Orbiting Carbon Observatory-2 Launch

NASA's Orbiting Carbon Observatory-2 spacecraft separates from the second stage of its United Launch Alliance Delta II rocket

Orbiting Carbon Observatory-2 on the Pad

Latest updates:

- Engineers have successfully established communication with the Orbiting Carbon Observatory-2.

- The Orbiting Carbon Observatory-2 has separated from the Delta II rocket that boosted it to space as planned, and has begun unfurling its twin solar arrays.

- The two stages of the rocket carrying the Orbiting Carbon Observatory-2 have separated. The fairing encapsulating the spacecraft has opened and has been jettisoned as planned.

- The Orbiting Carbon Observatory-2 has launched into the night skies above the Pacific Ocean.

The launch of NASA's Orbiting Carbon Observatory-2 (OCO-2) aboard a United Launch Alliance Delta II rocket is scheduled for Wednesday, July 2 at 2:56 a.m. PDT (5:56 a.m. EDT) from Space Launch Complex 2 at Vandenberg Air Force Base in California.

The launch team has completed troubleshooting of the launch pad water suppression system that resulted in the scrub of the launch attempt Tuesday. A valve that is part of the pulse suppression water system, which had operated properly during tests shortly before the launch countdown, failed to function properly during the final minutes of the launch attempt. The failed valve has been replaced with a spare, and the system is being tested in preparation for Wednesday's launch attempt.

The OCO-2 mission will produce the most detailed picture to date of natural sources of carbon dioxide, as well as their "sinks" -- places on Earth's surface where carbon dioxide is removed from the atmosphere. The observatory will study how these sources and sinks are distributed around the globe and how they change over time.

The launch weather forecast is unchanged, with a 100 percent chance of favorable conditions at liftoff, which is targeted for 2:56:23 PDT (5:56:23 EDT) at the opening of a 30-second launch window. OCO-2, the first dedicated NASA mission to monitor atmospheric carbon dioxide on global scales, has only a 30-second launch window each day. The launch window is short because the spacecraft needs to be precisely aligned within a series of Earth-observing satellites known as the "A-Train."

NASA Television coverage will begin at 12:45 a.m. PDT (3:45 a.m. EDT) Wednesday. For NASA TV downlink and schedule information and streaming video, visit:


The United Launch Alliance Delta II rocket carrying OCO-2 will lift off from Space Launch Complex 2 West at Vandenberg. Three solid rocket motors are ignited just prior to liftoff to boost the rocket, and are jettisoned about 100 seconds later. The main engine will cut off, a phase known as MECO for Main Engine Cut-Off, a bit more than four minutes into the flight. Eight seconds later, the rocket's first and second stages will separate.

During the second stage burn, the payload fairing, or launch vehicle nose cone, will separate into two halves, like a clamshell, falling away at approximately five minutes after liftoff. The second engine cuts out (SECO-1) about five minutes later.

The observatory and second stage will then coast in an intermediate orbit for about 40 minutes. The second stage engine will fire a second time (SECO-2) about 51 minutes after launch, placing the observatory into the desired orbit. Separation of the rocket and observatory will occur a little more than 56 minutes after liftoff and will be monitored by engineers using tracking data and a forward-facing video camera mounted on the Delta II second stage.

The remaining second stage of the rocket will perform further maneuvers to place it in a final parking orbit, and to avoid colliding with the OCO-2 spacecraft.

Three minutes after separation, the spacecraft will begin to deploy its twin solar arrays, and at about the same time, ground controllers expect to establish two-way communication with a ground station via NASA's Tracking and Data Relay Satellite System.

Six to seven weeks after launch, OCO-2 will be maneuvered into its final, operation orbit in the A-Train constellation, 438 miles (705 kilometers) above Earth.

The first science observations of carbon dioxide levels on our planet are slated to begin about 45 days after launch.

This Web page will be updated as various milestones occur on launch day.

For more information about the Orbiting Carbon Observatory-2, visit these sites:



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NASA's Jet Propulsion Laboratory in Pasadena, California, is responsible for project management of OCO-2. Orbital Sciences Corp. built the OCO-2 spacecraft. NASA's Launch Services Program at the agency's Kennedy Space Center in Florida provides launch management. United Launch Alliance of Centennial, Colorado, is NASA's launch service provider for the Delta II rocket.

OCO-2 is the second of five NASA Earth science missions to be launched this year. NASA monitors Earth's vital signs from land, air and space with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth's interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

For more information about NASA's Earth science activities in 2014, visit:


News Media Contact

Alan Buis
Jet Propulsion Laboratory, Pasadena, California
Steve Cole
NASA Headquarters, Washington

George H. Diller
Kennedy Space Center, Florida