Double impact: Sen article on icy Martian craters.

Icy Twin Craters on Mars

Icy Twin Craters on Mars

Bad Astronomy
The entire universe in blog form
March 10 2015 1:00 PM

Icy Twin Craters on Mars

Arima crater
Here's looking at you, red planet.

Photo by ESA/DLR/FU Berlin (G. Neukum)

I’ve mentioned a few times here that I write a biweekly column for, a site that has lots of news and blogs dealing with space exploration (Sen stands for “Space Exploration Network”). The news articles are free, but the blogs are subscription only.

My latest article there is one I’ve been meaning to write for some time: What phenomenon sculpted this weird pair of craters, each with a central pit in it? It turns out the answer is … layered.

Advertisement is worth the subscription price. There are a lot of good writers there, including my friends Emily Lakdawalla, Chris Lintott, and many more. Go check it out!