In just 80 seconds, NASA provides comprehensive insight about when to wear solar glasses during the total solar eclipse on August 21, 2017.

Note: This video only applies if you venture into the narrow, 70-mile wide path of totality. All of North America will be able to see a partial eclipse, where the moon will block out a portion of the sun. Under such conditions, you’ll never want to remove your solar shades during the celestial event.

Here’s the rundown:

Part 1:

Glasses on during the partial eclipse, which can last for an hour as the moon “invades” the sun.

Part 2:

Glasses on during the “Baily’s beads” (when almost the entire sun is covered), which are bright glimpses of sunlight that peek out from the valleys and mountains on the moon’s edge.

Part 3:

Glasses on during the “diamond ring,” when just a single flash of light pokes through the moon’s valley. This marks the last few seconds before “totality” hits.

Part 4:

Glasses off during totality, which will last as long as 2 minutes, 40 seconds on the West Coast but only 30 seconds in other locations. (Know before you go.)

Part 5:

Glasses on as the sun’s crescent begins to peek out from behind the moon.

Photos via Flickr / David Paleino, Flickr / Amy Loves Yah