NASA’s Hubble Space Telescope cracked a “glittering cosmic geode” in a new image of a triple-star system. One of the stars gives us a glimpse of what our own sun might have been like ...

Geodes are hollow rock formations often with quartz crystals, such as amethyst, inside. Amethyst geodes in Uruguay have been found in cooled lava flows, which date from the original breakup of the ...