Inflatable dinosaurs

PZ Myers explains how birds' lungs work (commenter "Raven" quotes a friend: "our lungs are two-stroke, and birds' lungs are four-stroke"), and describes evidence that some dinosaurs had the same arrangement, with continuous one-way airflow through the lungs propelled by an extensive system of air sacs extending into holes in their bones.

Enceladus

Still no pictures up from yesterday's extremely close Enceladus flyby. Other space news in the past couple of weeks pushed it out of the spotlight, so I didn't get any advance information on when the downlinks were supposed to happen.

Popular interest in Cassini has been low in general over the past few orbits, as the spacecraft mostly sends back hundreds of medium-inclination pictures of the rings and Saturn itself; some of these have been beautiful, but they tend to look the same after a while. The main rationale for this part of the mission has been to periodically get the rings between Cassini and Earth for the purpose of radio occultations.

Aside from these Enceladus pictures, there will also be a pretty good flyby of Mimas in early August. Then, starting in the fall, the spacecraft will be right in the equatorial plane and the visual focus will shift back from the rings to the moons, with better pictures of several of the little irregular ice-chunk moons that haven't been very clearly imaged before, and also Tethys, Dione and Rhea.