Mars Curiosity's Big Week: Evidence of Water, Radiation, and Lizards Discovered?

This has been a big week for Mars news, with some great (and not so great) videos coming out, made from the images provided by NASA's Curiosity rover. The news this week ranges from the groundbreaking, to the unwelcome, to the ridiculous. Let's start with the groundbreaking: Mars definitely once had water flowing over its surface.

Scientists now have definitive proof that much of mars once had water flowing across its landscape. While we've thought for a while that the red planet once held liquid water — and you can clearly see the ice caps at the poles of Mars — NASA announced on Thursday that Curiosity has provided the smoking gun. Well, more like the rounded pebbles.

A new study found that photos taken by Curiosity of several areas packed with rounded pebbles showed evidence the rocks had traveled long distances in water, and that the areas where the rocks were found were probably ancient riverbeds. The water-smoothed pebbles were snapped by Curiosity's cameras close to where the rover landed, in an area called Hottah, between Gale Crater and Mount Sharp. "We could see that almost all of the 515 pebbles we analyzed were worn flat, smoothen and round," said Asmus Koefoed, the co-founder of the study and research assistant at the Niels Bohr Institute at the University of Copenhagen in Denmark, in a statement, according to Space.com.

Another discovery this week, courtesy of NASA's Mars Science Laboratory, which delivered the Curiosity Rover to the planet, wasn't as exciting or encouraging as the confirmation that water once flowed on Mars. As we reported, humanity may never make it on Mars due to radiation poisoning.

A NASA study of radiation levels taken by Curiosity found that a person on Mars would be exposed to several hundred times more the amount of radiation on Earth. During a round trip to Mars, which would take several years to complete, astronauts would be exposed to cosmic rays and particles coming from solar flares and other big events on the surface of the sun. Both are sources of high radiation that could increase the astronauts' risk of cancer.

"In terms of accumulated dose, it's like getting a whole-body CT scan once every five or six days," said the study's leader, Cary Zeitlin, a scientist at the Space Science and Engineering Division of the Southwest Research Institute in Boulder, Colo., according to the Guardian. Zeitlin's study was published in this week's edition of the journal Science.  

Finally, we have the ridiculous, but fun, Mars-related "news" that may take your mind off of the radiation. A self-described "UFOlogist" has spotted what may be either a Martian rat or lizard hiding among the rocks in one of the images beamed back by Curiosity.

As we previously reported, the photo was taken by the Mast Camera on NASA's rover, and the "creature" was "discovered" by Scott C. Waring of UFO Sightings. Maybe it was a squirrel. Another post on UFO Sightings claimed that NASA is letting animals go free on the surface of Mars "to test how long it would live on the surface of Mars." A squirrel, a lizard, a rat, or a rock—I'm guessing what NASA continues to find by studying the rocks will be more significant than the pareidolic visions of UFO enthusiasts. But it sure is fun to think about.