This review, which is one of the final key steps for all Ariane missions, validated the launch readiness of Ariane 5, its Herschel and Planck payloads, the Spaceport’s infrastructure and the network of downrange tracking stations.  It clears the way for tomorrow’s rollout of the vehicle from its final assembly building to the ELA-3 launch zone.

Ariane 5’s payload fairing carries depictions of the Herschel and Planck spacecraft and a description of their deep-space mission goal.

The heavy-lift Ariane 5 ECA will make an unusual morning departure on Thursday, with its liftoff scheduled for 10:12 a.m. local time from French Guiana.

Herschel is riding in the Ariane 5’s upper payload position, and will be deployed by the launch vehicle at just under 26 minutes into the flight. This 3,400-kg. passenger will be the largest space telescope ever launched, and is designed to provide astronomers with their best views of the universe at far-infrared and sub-millimeter wavelengths.  Herschel incorporates a 3.5-meter-diameter mirror that will provide data for studies of the formation of stars and galaxies.

Planck has a mass of 1,920 kg., and is integrated in the lower position of Ariane 5’s payload “stack.”  It is located underneath Herschel, encapsulated in the launcher vehicle’s SYLDA dispenser system. The SYLDA dispenser will be jettisoned at approximately 27 minutes after liftoff, allowing Planck to be released at 28 min. 29 sec. into the flight.

Planck and Herschel were built for the European Space Agency, and production of the two spacecraft was carried out by Thales Alenia Space-led industry teams.  After their deployment by Ariane 5, both Planck and Herschel will follow 1.5 million-kilometer trajectories to the Sun-Earth system’s second Lagrange point (L2) to carry out their scientific missions.