Also, on Mars: Just follow the road to the right from the Patrol Mars spawn point. You'll reach a Cabal stronghold where the Vex are constantly attacking the Cabal. Pop a Resupply Code and Blue Polyphage (so you can get extra Glimmer from both Vex and Cabal), and just make a big speed-kill-circle around the whole area. You should be able to get 4-5 circuits around the area before needing to pop more of the consumables. There's Cabal Centurions, Vex Hobgoblins... and a bunch of weaker mobs as well. It'll be like robbing Scrooge McDuck...