On Valentine’s Day 36 years ago, at the request of Carl Sagan, NASA turned Voyager 1's camera back toward home for one last look.

From 3.7 billion miles away, it captured this: a mote of dust suspended in a sunbeam.

Here is how Carl Sagan beautifully described it:

“Look again at that dot. That's here. That's home. That's us. On it, everyone…