After some moments the ghost light will appear down the road.

FORBES: Students Use iPhones to Debunk Ghost Story

Written by John Kamps ("Zathura") and David Koepp ("Indiana Jones and the Kingdom of the Crystal Skull") and directed by Koepp, "Ghost Town" is a light comedy about a misanthropic dentist, Bertram Pincus, who develops an unwelcome sixth sense after losing his vital signs for several minutes during a routine colonoscopy.

CNN: Review: Gervais gives edge to 'Ghost Town'

Dr. SCHAWINSKI: The reason we call it a ghost is because we believe it is something called a light echo.

NPR: What Makes Our Solar System Special?

So Gilder took to the quadrangle once more and read another ten dozen books, this time on light and the electromagnetic spectrum, until he could pass for the ghost of Richard Feynman, sans bongo drums.

FORBES: Digital Rules