Watch, then read the lesson.
Every lesson is also on YouTube: Sky Science playlists on YouTube.
How to predict a great sunset
Three clues decide whether tonight's sky catches fire, and one of them is 100 km away.
2:48
Why Kp 5 Doesn't Mean You'll See the Aurora
Kp describes a planetary geomagnetic disturbance. Aurora viewing also depends on the oval, darkness and clouds where you are.
2:47
How to See a Meteor Shower
A shower advertised at 150 meteors an hour may yield far fewer in your backyard. Learn how radiant height, light and cloud change the count.
The forecast that explains itself.
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More from Forecast Bar
Learn: two-minute explainers
Short videos on the sky and the weather, each with the lesson written out.
Storm Science
Storm cells and whether one will hit you, hail size and the storm report, and what Slight, Enhanced and Moderate risk mean on a severe weather outlook.
Weather Data, Decoded
The numbers and maps behind every forecast: reading radar like a meteorologist, how live radar reaches your phone, what AQI and PM2.5 mean, how apps predict rain to the minute, and why two weather apps can disagree.