Broadcast Outage: We're investigating a broadcast transmission failure affecting the San Luis Valley from Antonito in the south to Salida in the north. We're working to resolve this issue. You can stream our live broadcast HERE or via the RMPBS+ App.

Stream live and on-demand content now on our new app:

RMPBS+

Donate

Help tell more stories in 2026 - make a year-end gift!

Be Smart show's poster

Science and Nature

Mars Used to Be Blue... Then Something Happened

Join Joe Hanson as he explores curiosity and illuminates the science behind… well, everything.

Mars Used to Be Blue... Then Something Happened

Season 13 Episode 12 | 11m 8s | CC

Why is the Martian sky red by day… but blue at sunset? And how did it used to look more like Earth? The strange story of Mars’ skies can reveal a lot about the Red Planet's past, and the surprising ways it is more like Earth than you may know.

share

Be Smart

Watch more episodes

The Intelligence Test Where Ants Beat Humans

How thousands of tiny brains, obeying simple rules, solve problems no individual can understand.

The Weird Science That Lets Insects Fly in the RainThe Weird Science That Lets Insects Fly in the Rain

Insects and birds have an awesome superpower that repels water and keeps them airborne in the rain.

Why Your Grandma Is an Evolutionary Mystery

This is one of the weirdest mysteries of human evolution: Why do we have grandmas?

Subscribe to Our Newsletters

Get trusted Colorado stories, programs, and events from Rocky Mountain PBS straight to your inbox.

Set Your Preferences >