Text image: Now I understand what is it dark matter!
I don't think you have to be an astrophysicist to know how to flush a toilet so the next user is not left to discover your "dark matter"!
Dedicated to whoever defecated (and left an enormous, stinky shit) in the toilets in the lobby of the Faculty of Science of the Universidad Autonoma de Barcelona on 14 April 2009.
Special thanks to wordreference people!
Additional information: Dark matter UAB Wordreference
