In 1927, twenty-nine scientists gathered at the fifth Solvay Conference. That's a lot of mental bandwidth all in one place, and now a user on Reddit has given the venerable photo a little modern love.

President Obama took to Reddit Wednesday afternoon, for a half hour session where users could ask any question they wanted. Of course, lots of people would jump at that chance, so it didn't take long before the system crashed.

Engineers and staff from NASA's Jet Propulsion Laboratory, including plenty of the folks responsible for landing the Curiosity rover safely on Mars, took to Reddit to answer any and all questions about the Mars Science Laboratory mission. Well, they tried to answer — the session exploded and right now has over 7,000 comments. Here, we've collected 10 questions and answers we felt stand out from the bunch. The questions from Redditors and answers from the team at JPL are presented unedited.