What does Mars's reddish hue have to do with its watery history?

We'll talk about it, this week on Planetary Radio.

I'm Sarah Al-Ahmed of the Planetary Society, with more of the human adventure across our solar system and beyond.

Mars has been read for billions of years,

but scientists may have finally cracked the case on what iron compound actually gives it that color.

This week I speak with planetary scientist Adomas or Adam Valentinas from Brown University.

He's the lead author on a new study that suggests that Mars's surface dust is dominated not by hematite, as we long believed, but by a different water-rich mineral, ferahydrite.

What does that mean for Mars's watery past?

We'll get into the science, the implications for future human explorers on Mars, and what it tells us about the red planet's timeline for habitability.

Then we'll revisit one of the most iconic discoveries in Martian history, the hematite

blueberries found by the Opportunity Rover in What's Up.

If you love planetary radio and want to stay informed about the latest space discoveries,

make sure you hit that subscribe button on your favorite podcasting platform.

By subscribing,

you'll never miss an episode filled with new and all-inspiring ways to know the cosmos and our place within it. For decades, scientists have studied the red dust coating Mars and developed a strong

working hypothesis about what gives the planet its distinctive color.

The leading idea was that iron in the soil reacted with small amounts of water and oxygen over long periods to form hematite.

It's a familiar form of iron oxide or rust that we have here on Earth.

This fits well with our broader understanding of Mars as a cold,

dry planet that once held water, but lost it billions of years ago. Earlier studies of iron

oxide and Martian dust, based primarily on spacecraft observations, did not detect any water

bound within the mineral structure. This led researchers to conclude that the dust must be composed of an

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