Next time you're heading to Mars, bring your clubs. Am I right?!
Technically, the hole wasn't supposed to be a golf hole. As that beast of caption explains, it was actually the result of a test Curiosity conducted on Mars' soil which has produced some interesting early results.
The rover found a large amount of methane in the soil. Methane is very commonly produced by living organisms, so unless it was brought to Mars by astroids (as scientists accept may be the case), it was almost certainly left there by living microbes, or by organisms that once lived on Mars but have since gone extinct.
Exciting stuff. No word yet on whether the martians are golfers.