Blue Origin launched its second heavy-lift New Glenn rocket Thursday, putting two small NASA satellites onto a long, looping course to Mars to learn more about how the sun has slowly blown away the red planet’s once thick atmosphere.

A United Launch Alliance Delta 4 rocket will deliver the U.S. Air Force’s tenth Wideband Global SATCOM communications satellite to a supersynchronous transfer orbit around 37 minutes after lifting off from Cape Canaveral.

Launching for the 50th time, an Atlas 5 rocket flew a milestone mission Wednesday in deploying a Global Positioning System satellite for the worldwide utility.