A mishap shortly after launch led to the loss of the Orbiting Carbon Observatory (OCO), a NASA environmental monitoring satellite, on 24 February. The satellite crashed into the ocean off Antarctica.

"It's a major setback," says Paul Palmer, a climate scientist at the University of Edinburgh, UK, who is part of the OCO science team. It will be particularly devastating for the tight-knit group of scientists and engineers who have devoted much of the past decade to the project. "These guys have sweated OCO for seven or eight years," he says.

OCO, which cost US$273 million, was designed to measure carbon dioxide levels at various depths in the atmosphere with high enough precision to allow the sources and sinks of the gas to be assessed. It would have provided researchers with a comparatively high-resolution global picture of how carbon dioxide is absorbed by oceans, forests and other components of the Earth system.

The satellite was launched aboard a Taurus XL rocket at 4:55 a.m. local time from Vandenberg Air Force Base in California. Shortly after launch, controllers announced that the protective clamshell 'fairing' that surrounded the satellite had failed to separate properly.

The Taurus was built by Orbital Sciences Corporation of Dulles, Virginia; the company was also the main contractor on the spacecraft itself. This was the eighth launch of a Taurus rocket and the second failure. An investigating board was being set up as Nature went to press. The next payload booked for launch on a Taurus is another NASA satellite, Glory, which will study clouds and aerosols. It will not now be launched until OCO's loss is understood.

OCO was one of two carbon dioxide-monitoring satellites to launch this year. In late January, the Japanese Aerospace Exploration Agency launched the Greenhouse Gases Observing Satellite (GOSAT), which will monitor levels of methane, water vapour and carbon dioxide. That satellite seems to be functioning normally.

The two satellites would have been complementary to each other. Whereas GOSAT provides high spectral resolution of gases in the atmosphere, OCO would have provided detailed spatial resolution of carbon dioxide. In addition, the two satellites would have allowed scientists to check their data against one another. "Having two satellites was going to make life a lot easier," says Palmer.

Credit: NASA TV