关于这张图
This image of a rock target nicknamed "Thunderbolt Peak" was created by NASA's Perseverance Mars rover using the Planetary Instrument for X-ray Lithochemistry (PIXL) – an instrument on the end of the rover's robotic arm that determines chemistry and mineral composition by zapping a rock with X-rays. Each blue dot in the image represents a spot where an X-ray hit. By measuring the interaction of the X-rays with the rock, scientists can map which minerals are present in a rock's surface and how much of them, plus the size, shape, and crystallinity of the rock grains. In the case of Thunderbolt …
