NASA's Curiosity Mars rover discovered sulfur crystals inside a rock after accidentally crushing it on the 4,200th Martian day of its mission. The rover drove over the rock on May 30, 2024, revealing the crystals. The discovery provides a unique opportunity for the rover to study Martian sulfur up close.

Source: https://www.nasa.gov/image-detail/nasa-iotd-curiosity-takes-a-close-look-at-martian-sulfur-crystals/