NASA's Mars rover Curiosity used its Radiation Assessment Detector (RAD) to measure radiation exposure on the way to Mars. Now, it's recording similar data on Mars' surface. This image is a composite self portrait taken on Feb. 3, 2013.
There was great fanfare when the Mars Science Laboratory launched in November 2011, and again when its precious cargo — NASA's Mars rover Curiosity — touched down on the red planet in August 2012.
The eight months in between had drama of their own. Curiosity was constantly bombarded with radiation as it traveled through space — high-energy protons thrown out by the sun, and galactic cosmic rays slicing through the solar system from distant supernovas.
In the more than eight years since it was written, the open-source operating system Ubuntu's "Bug #1" has been seen as a rallying call. After all, the bug's title is "Microsoft has a majority market share."
But the entry was officially closed Thursday, partly because the "broader market has healthy competition" as Ubuntu leader Mark Shuttleworth writes in his comments on closing the bug today.