The 2011 film Another Earth, directed by Mike Cahill, explores very human questions against an improbable backdrop. Artists Public Domain/The Kobal Collection hide caption

itoggle caption Artists Public Domain/The Kobal Collection

The Universe of Particles exhibition at CERN in 2011. Fabrice Coffrini/AFP/Getty Images hide caption

itoggle caption Fabrice Coffrini/AFP/Getty Images