The Planck spacecraft has arrived at the Centre Spatial Guyanais in Kourou, French Guiana, where it is scheduled to be launched atop an Ariane 5 rocket on April 16.

The spacecraft arrived from Belgium via an Antonov An-124 cargo plane on Feb. 19.

It will be launched with the Herschel spacecraft, though the two missions will separate shortly after launch and operate independently from each other.

Planck is a European Space Agency mission, with significant participation from NASA. NASA's Planck Project Office is based at NASA's Jet Propulsion Laboratory in Pasadena, Calif.

NASA contributed mission-enabling technology for both of Planck's science instruments. U.S. and European Planck scientists will work together to analyze the Planck data.