
On Mars, you can't judge a book-shaped rock by its cover.
NASA's Curiosity rover ran across the hardcover-shaped feature on April 15, which happened to be the 3,800th Martian day (or sol) of the long-running mission.

On Mars, you can't judge a book-shaped rock by its cover.
NASA's Curiosity rover ran across the hardcover-shaped feature on April 15, which happened to be the 3,800th Martian day (or sol) of the long-running mission.