James Turrell discusses his ongoing land art piece, Roden Crater, created within a pit formed by an extinct volcano in the Arizona desert. ART21: Where are we, right now? TURRELL: Well, right now ...

If it nails its touchdown on the lunar surface, Athena will unpack its payloads, including a Micro-Nova robot named Grace that will hop into a nearby crater and then hop back out. The robot is ...

Hazards include high levels of volcanic gas, falling volcanic fragments near the vents, unstable crater walls, ground cracking and potential rockfalls — especially around areas that have been ...