[s1e4] A Sky Full Of Ghosts Access

"A Sky Full of Ghosts," the fourth episode of Cosmos: A Spacetime Odyssey hosted by Neil deGrasse Tyson, explores the nature of light, gravity, and time, revealing how the night sky acts as a historical record . The episode explains that because light travels at a finite speed, observers on Earth are looking back in time, seeing "ghosts" of stars that may no longer exist . For educational resources and guided notes on this episode, visit Teachers Pay Teachers .