> ## Content Index
> Fetch the complete content index at: https://www.cascadepbs.org/llms.txt
> Use this file to discover other available public pages before exploring further.

# Mars Used to Be Blue... Then Something Happened
- URL: https://www.cascadepbs.org/show/its-okay-be-smart/episode/mars-used-to-be-blue-then-something-happened-btsexi/
- Published: 2025-10-27T03:30:57.000Z
- Updated: 2025-10-27T04:00:13.000Z
- Description: Why is the Martian sky red by day… but blue at sunset?
- Author: Cascade PBS Staff
- Tags: Be Smart, Season 13, Episode 12, #ZZZ_Episode_b0fac8cb-c6c7-45f6-8c41-2c5dc8b8425d, #episode, #ZZZ_Show_dc38a6e9-266e-43c1-b647-45e7445fad27, #v1.16

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.