Thundereggs look like regular rocks from the outside, but contain intricate and colorful mineral patterns inside — often made ...

Above Wenatchee, spires reveal volcanic history in 44-million-year-old rock. High above the city of Wenatchee, Washington, a group of spires made of a unique type of 44-million-year-old rock tell the ...

One of the largest canyons in our Solar System carved its way through several layers of ancient volcanic eruption debris, a recent study reports. Valles Marineris is a titanic network of deep cracks ...

A mosaic of two pictures showing the rover arm after scanning and sampling one of the rocks discussed in the paper. The rock itself is in the lower right and clearly shows the hole where the sample ...