Herschel and Planck will be launched together on an Ariane 5 from Europe’s Spaceport in Kourou, French Guiana. The satellites
will be placed inside the fairing of the launcher; Planck at the bottom, Herschel on top. They will separate shortly after launch
and proceed independently to different orbits around the second Lagrange point of the Sun-Earth system, or L2. The boosters
of the Ariane 5 will burn for slightly less than 2.5 minutes and its main and upper stage engines for about 25 minutes to set
Herschel and then Planck on the path to L2.
On reaching L2, Planck will be injected into a Lissajous orbit (a kind of orbit that winds around a torus without closing onto
itself) using the onboard thrusters.