(Maria de la Heras)

Since Johannes Kepler used Mars to explain the organization of the cosmos back in the 17th century, people have been royally obsessed with the Red Planet... Why everyone keeps talking about Mars. Weir’s film is certainly one reason Mars is front and center in the zeitgeist.“I’ve been a lifelong fan of space and space travel. So I don’t remember a time when I wasn’t interested in Mars. It’s endlessly fascinating,” he says. “For instance: The largest mountain in the solar system is Olympus Mons on Mars. It’s three times the height of Mount Everest. But it is also very wide. The base is about the size of Arizona. This means the actual grade, the steepness of the land, is so subtle that the curvature of Mars has a larger effect than the grade of the terrain. So if you were on Olympus Mons and looked all around you, you would think you were standing on a perfectly flat plain.”

What to make of the recent announcement about water on Mars. “NASA’s announcement means there’s a tangible place to look for evidence of life on Mars,” says Weir. “It’s pretty exciting.” Nonetheless, as Petranek points out, there’s no reason to get too giddy; the news is confirmation of previous suggestions that Mars has seasonal water flows. “Careful observers of research from Mars orbiters were not in the least surprised by the announcement from NASA, he says. “Furthermore, we know there is lots of water ice at the poles, lots of water bound up in the Martian soil as ice, and that there are entire glaciers of ice covered by a thin layer of dust.” What’s perhaps been missed in the excitement at any water on Mars is that actually, there might be a whole load of it there. “Jim Green, director of planetary science at NASA, told me last month over coffee that ‘Mars is loaded with water. There is an incredible amount of water on the planet,’” says Petranek.