LOS ANGELES, July 2 (Xinhua) -- U.S. space agency NASA launched Orbiting Carbon Observatory-2 (OCO-2) spacecraft early Wednesday from California into the night skies to study global warming, NASA TV showed.
The United Launch Alliance Delta 2 rocket carrying the OCO-2 spacecraft, the first dedicated NASA mission to monitor atmospheric carbon dioxide on global scales, blast off at 2:56 a.m. PDT (0956 GMT) Wednesday from Space Launch Complex 2 at Vandenberg Air Force Base in California.
Engineers have successfully established communication with the Orbiting Carbon Observatory-2, NASA said in a statement.
"I' m alive! Congratulations to the entire OCO-2 team," NASA said via its official Twitter account,"I' ve phoned home. Ground controllers hear me loud and clear!"
The observatory has just a 30-second opportunity to launch. The timing has to be so precise because OCO-2 will join the A-Train, a constellation of five other international Earth observing satellites that fly very close together to make nearly simultaneous measurements of our planet.
"The only way to accomplish a polar orbit from U.S. soil is to launch from Vandenberg," said Tim Dunn, NASA's launch manager for the flight.
Six to seven weeks after the launch, OCO-2 will be maneuvered into its final, operation orbit in the A-Train constellation, 705 km (438 miles) above Earth.
The new satellite, dedicated to studying atmospheric carbon dioxide on global scales, 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.
"There's quite a lot of urgency to see what we can get from a satellite like OCO-2," said David Crisp, the science team lead for the mission.
The mission was supposed to launch on Tuesday, but was canceled when a problem in a Vandenberg Air Force Base Space Launch Complex 2 pad water system was discovered. The system provides sound suppression to dampen acoustic waves at liftoff and protects a launch pad flame duct.
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, the space agency said in a statement.
The mission marks NASA's second try to measure atmospheric carbon dioxide from space. In 2009, the space agency launched the origin OCO satellite aboard a Taurus XL rocket. Shortly after liftoff, the rocket crashed into the ocean off Antarctica. The cost of that mission was 209 million U.S. dollars, according to a NASA investigation.
Carbon dioxide is a critical component of Earth' s carbon cycle and the leading human-produced greenhouse gas driving changes in Earth' s climate.
According to NASA, before the Industrial Revolution, there were about 280 molecules of carbon dioxide out of every million molecules in the atmosphere, that is, 280 parts per million.
By 2014, at approximately 400 parts per million, atmospheric carbon dioxide has now reached its highest level in the past 800,000 years.
The burning of fossil fuels and other human activities are currently adding nearly 40 billion tons of carbon dioxide to the atmosphere each year, producing an unprecedented buildup in this greenhouse gas.
But less than half the carbon dioxide emitted into Earth' s atmosphere by human activities stays there, while the rest is absorbed by the ocean and natural land "sinks." Scientists hope the OCO-2 will help resolve the longstanding scientific puzzle of where this carbon is going.
"Knowing what parts of Earth are helping remove carbon from our atmosphere will help us understand whether they will keep doing so in the future," said Michael Gunson, OCO-2 project scientist of NASA' s Jet Propulsion Laboratory.
"Understanding the processes controlling carbon dioxide in our atmosphere will help us predict how fast it will build up in the future. Data from this mission will help scientists reduce uncertainties in forecasts of how much carbon dioxide will be in the atmosphere and improve the accuracy of global climate change predictions," he said.