Live coverage: Vega rocket launches with LISA Pathfinder

Humankind’s largest emissary to Mars in a generation is set for blastoff Monday, when Europe and Russia will dispatch a mission to unravel the mystery of Martian methane.

The mission marked the first time that an American-made rocket launched Europe’s answer to the GPS satellite constellation. Liftoff from Launch Complex 39A happened at 8:34 p.m. EDT (0034 UTC) on Saturday, April 27.

The 13th and 14th operational members of Europe’s Galileo navigation satellite network are set for liftoff Tuesday aboard a Soyuz rocket from French Guiana. Track the progress of the flight with this timeline of key events.