21 August 2017 Last updated at 19:15 BST
A total solar eclipse is sweeping across the States, plunging whole areas of the US into complete darkness for a few short moments.
Here is the moment when some of the first pictures of the total solar eclipse were seen from a special Nasa aircraft.
You can hear how excited everybody is!
For more updates from the Great American Eclipse 2017, click on this link.
Millions of people across the US are enjoying one of the most incredible space sights that you can see from the Earth.