NASA's Glory satellite, which launched early this morning from Vandenberg Air Force base in California, has failed to reach orbit.
NASA says the instrument readings indicate that the fairing - the protective shell on top of the Orbital Sciences Taurus XL rocket - didn't separate as intended.
For the first three minutes, everything went as planned. But then at an altitude of about 100 miles, and with the spacecraft traveling at 9,500 miles per hour, something went wrong. With the extra weight of the fairing holding it back, it was unable to keep ascending.
"The vehicle's speed is indicating underperformance, which is expected to affirm not separating," said a spokesman in a video commentary.
"We have a report that the system did pressurize, however we still have no indication of the fairing separating."
Glory was originally set for launch on February 23rd, but was delayed twice because of unspecified technical issues; it's not known if these are related to today's failure.
The satellite was intended to carry out a three-year mission investigating how the Earth's atmosphere is affected by the sun and by tine aerosol particles. Scientists had hoped to get a far more accurate picture of the amount of energy entering and exiting the Earth's climate system. It was also carrying three smaller 'Cubesats' designed and built by students.
Glory is believed to have come down in the ocean.
It's the second time in two years that a Taurus XL launch has failed for this very reason. In October 2009, NASA's Orbiting Carbon Observatory mission was unable to release its satellite because a fairing failed to separate.