Life on Mars

Astronauts Helen and Tim have travelled from planet Earth on a mission to Mars. They are overjoyed to successfully touch down their landing module on the rocky martian surface. When they lift up the door to the landing module, the answer to their mission question "Is there life on Mars?" is answered a little sooner than they were expecting.

Two green aliens are waving at them. One stands on a large, red rock waving a red flag. The astronauts earthly instincts are telling them to run away from the red flag, for they have always signified danger. However, perhaps on Mars a red flag is a symbol of goodwill and friendship? 

Should they stay on the planet and learn more about these green aliens, or should they run back to the landing module and quickly get back into orbit?