This is an incredible Cassini photo showing two amazing phenomena. The blue areas are Saturn’s northern lights (aurora borealis, just like on Earth!). Underneath the blue there is a dark hexagon 15,000 miles in diameter. This is Saturn’s polar vortex (again, just like Earth, but six-sided instead of round.
Boundary Waters Canoe Trip 2008
I learned to canoe in Northern Minnesota and the BWCA. I recently returned for a five day trip with an old friend. We went to the extreme northeast corner along the Canadian border. The lakes in this area are mostly long and narrow, running west to east between steep hills. The water clarity was remarkable. We saw bear, beaver, loon, eagle, osprey, and many smaller birds. Our route included the Royal River, which was beautiful and very different from the large lakes. Wild rice was falling into our canoe as we passed. At one point we even had to pull over a beaver dam.
Better Passwords?
The best passwords are completely random—strong but almost impossible to remember. This report from the National Institute of Standards and Technology (NIST) suggests a better solution—long pass phrases.
Entropy is a measure of password strength. The more entropy a password has, the harder it is to crack. Many systems enforce dictionary and composition rules (numbers, mixed case, punctuation) on short (less than ten character) passwords. This graph on page 23 of the NIST report shows that dictionary rules do not improve longer passwords, and the boost from composition rules is fairly small. A simple twelve character pass phrase (a-z plus spaces) is as strong as an eight character rule-based password, but can be much easier to type and remember. Throw in one digit and you’ve got a very strong credential indeed! I’ve written a quick three step approach for the UF campus system (which unfortunately does not allow spaces).