The Red Planet Is Only Red on the Outside

A rusty sheen turns Mars red, but beneath the rock is a plain gray

Curiosity’s scoop holds some of the grey rock freed up by the drill. Photo: NASA/JPL-Caltech/MSSS

Still trundling along on the surface of Mars, the charismatic Curiosity rover hit another milestone recently when it offered us our first glance beneath the planet’s red surface. Nicknamed the Red Planet for its characteristic rusty sheen, NASA scientists were surprised to see that beneath a thin exterior the planet’s crust is but a plain gray. NBC’s Cosmic Log:

We’re seeing a new coloration for Mars here, and it’s exciting for us,” Joel Hurowitz, sampling system scientist for the Curiosity mission at NASA’s Jet Propulsion Laboratory, told reporters during a teleconference on Wednesday.

That the subsurface rock is gray, not red, could be a good sign in the quest to find organic material on Mars. Oxidation, the chemical process that turns Mars’ iron-rich rocks red with rust, is hard on organic material.

A drill hole shows the gray subsurface. Photo: NASA/JPL-Caltech/MSSS

According to the Associated Press, the Curiosity team confirmed on Monday that the scooped rock was successfully moved into the rover’s on-board laboratory. Over the next few weeks, NASA scientists will test the drilled sample, trying to figure out its chemical composition.

More from Smithsonian.com:

How to Follow Every Second of the Curiosity Mars Mission
Curiosity Nails It: Mars Used to Have Flowing Water

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