In 2003, I had temporary custody of a Mars MOLA globe and had my first real look at its surface. This started at the Blue Ash Airport Days, north of Cincinnati. A Guard member assigned to weekend security, SSgt Mike Harter, looked at the globe on Saturday and returned the next day with a new idea. The thought hit him overnight that Hellas Planitia isn't the result of an impact: “It's a sinkhole!” (collapse structure).

I found a picture of the Hellas Basin from NASA/JPL showing the full area which was taken from an angled view to show detail. The area strikes me as one that had sunken into the planet. The sides of the basin are very steep, practically straight up-and-down. There isn’t a raised brim around the basin as I would expect from a meteor; it looks more like a vacuum force sucked the land into the planet, such as by the settling of gases and elements in the cooling and forming of the planet.

Anyway, the globe came home with me after the event. With the new mindset from Mike's revelation, I had a revelation of my own: Mars had bubbles! Some of the “meteor” craters on the surface of Mars – and other planetary bodies - are the remnants of burst bubbles!

Robotic Exploration