More interesting data from our web statistics: rankings of the most popular images on our website. Some you’d expect to get lots of hits: special campaigns like Phoenix lander hardware and Phobos, and of course old favorites like a certain feature in Cydonia. Others have made a splash in the news, like the avalanche caught in action and a deep pit that might be the entrance to a cave – whether their popularity on our website is a cause or effect of the media coverage.

I find it interesting to see which “regular” images, out of the thousands we’ve taken, caught people’s attention – in May, for example, gullies in a crater wall and ridges in Huo Hsing Vallis (left) were popular. June saw lots of hits on this beautiful image of the north polar layered deposits (above) and this image of delicate-looking, multi-tendriled slope streaks.

In July, the “Mystery Mounds” (PSP_008778_1685 and PSP_008548_2205) were popular, presumably because they are so “mysterious” – ? (By the way, these two areas, despite their similar titles, are nowhere near each other on Mars.) Lesson learned: We should give more of our images “sexy” titles.

It seems the landslides in PSP_007338_2640 have caught a lot of attention!

There has been a lot of online and print news coverage: CNN, Time, Fox News, Astronomy, Space.com, New Scientist, National Geographic, and our local Arizona Daily Star, among many others. The New York Times made a really nice slide show that includes the avalanche, the Earth-Moon image, as well as other great images from our big PDS release. Blogs are talking about it (Cumbrian Sky and the Bad Astronomy Blog, to name just two). People over at unmannedspaceflight.com are discussing the avalanches a lot, too. (I’m sure there are tons I’ve missed – apologies – if you feel left out, post it in a comment below!)

A co-worker heard NPR’s Wait, Wait, Don’t Tell Me featured a question about the avalanches on Saturday. It was even the Astronomy Picture of the Day yesterday!

I’ve talked personally to a lot of people about it, too. It’s amazing how it’s caught everyone’s interest. I think most people who see it for the first time have the same “Holy crap!” reaction that we all had when we first saw it here at HiROC. Then they start trying to figure out what’s going on, what caused it, what it means, how we can take more data and look at past images to narrow down different hypotheses… which is exactly the process that scientists go through!

The best part of the story, I think, is how the landslide was serendipitously captured in an image, and then accidentally noticed! HiRISE has sent back such an incredible volume of highly detailed data, no one person has time to study it all in full resolution. We’ve released 17 Terabytes, thousands of images, and it’s very likely that more surprises like this are waiting to be discovered in them. So go look at more HiRISE images; let us know what you find! We can’t wait to see how Mars can surprise us further.

Thanks for being as excited about HiRISE and Mars as we are!

HiRISE caught an avalanche in action! http://hirise.lpl.arizona.edu/PSP_007338_2640

It was so exciting to find this image! The image was intended to be part of a series of seasonal monitoring observations of a dune field. We’re watching to see how the winter carbon dioxide frost disappears as spring comes to the northern polar areas (which is pretty cool in itself! See PSP_007043_2650, for example.) PSP_007338_2640 happened to be the first image we took after powering back on after a safing event. So we were examining the image to make sure the camera was still working OK (it is – as you can see from this beautiful image & the many others we’ve taken since!). If it hadn’t been for that, we might not have noticed this for weeks! (In case you haven’t noticed, we have a LOT of images to look at! )

My first reaction was just, “What is that?” So I asked some of the scientists around HiROC, and they got excited, too. Everyone was talking about it all day, putting together ad-hoc color products (the full color processing takes a while to get through our processing pipelines) and looking at other images nearby for similar events. Because this was part of a series of images in the same spot, we had a “before” image as well (PSP_007140_2640). It’s a little hard to compare the two images because the bright carbon dioxide frost is changing as well, and we took the two images from different angles. But you can see in the second image that there are some spots up above on the cliff that are missing their bright frost covering. Perhaps that’s where the rock (or ice) fall started? The springtime sun is warming these icy layers, which could cause sublimation (solid ice changing to gas). Certainly there is a lot of dust being raised to form this big cloud, too, whether the dust was mixed in with the ice blocks, or just kicked up off the lower, dustier layers. As we continue monitoring this site and other polar areas, we’re sure to learn a lot more about the processes captured in this image.

ETA: Emily Lakdawalla made a great animation of the before/after shots, posted on the Planetary Society blog. So cool!