Today, it’s so cold on Mars that at its south pole, in winter, a meter-thick layer of carbon dioxide ice forms. It’s so cold that the atmospheric pressure dips because so much of the atmosphere freezes. It’s so cold that Fastook still looks at the polar ice caps, with their beguiling spiral cracks, shakes his head and moves on. Though Fastook has been able to model other glaciers on Mars, the ice caps are too thick, too complex for his equations to handle.
That could change soon. For the last two years, a radar instrument has been in orbit around Mars, measuring the thickness of the polar ice caps, among other things.
“I still look at the polar ice caps and think they’re too hard,” Fastook says, “But within the next few years, I might do a model.”
In the meantime, there’s one question that continues to drive him. It’s the question that captivated him in 1976, when those first images came back from Mars. It’s the question that he asks about the glaciers he models on Earth. It’s so basic, so fundamental, and yet the answer could hold the key to past, current and future life on the red planet.
“In terms of climate change on Mars, there’s all this evidence of surface water flowing across Mars. There are river valleys. There are lakes with shorelines. There are spillways. There’s all this evidence of a lot of liquid water flowing around the surface of Mars,” Fastook says. “But where’s the water now? If we want to go there, we need to know where the water is. We need water to make fuel to come home again. Was there ever life there? Is there life there now?”
Image Description: Mars polar ice cap