Friday, June 30, 2006

Protoplanetary disk shapes, flipping life’s switch and Cassini at half-way mark

Welcome! “Alien Life” tracks the latest discoveries and thoughts in the various elements of the famous Drake Equation. You may notice that this and future entries are shorter than usual; Career, family and book deal commitments have forced me to cut back some of my projects. Now, here’s today’s news:
g Stars - Recent discoveries add yet more variety to the bewildering diversity of protoplanetary disk shapes - ranging from donuts to spirals - that astronomers are finding as they study the birthing grounds of planets around other stars. See http://www.astrobio.
g Abodes - New technologies are enabling scientists to determine precisely the extent and causes of Earth's short-term wobbling. Like a spinning top, Earth wobbles as it rotates on its axis. In fact, it displays many different wobbling motions, ranging in period from a few minutes to billions of years. Some of these are well studied, like the Chandler wobble of 433 days and the annual wobble, which together can tilt Earth's axis up to 10 meters [30 feet] from its nominal center. See
g Life - Somewhere on Earth, close to 4 billion years ago, a set of molecular reactions flipped a switch and became life. Scientists try to imagine this animating event by simplifying the processes that characterize living things. New research suggests the simplification needs to go further. See
g Intelligence - Can Darwinism explain the birth and extinction of art movements, or the enduring appeal of Jane Austen? See http://
g Cosmicus - As the Cassini spacecraft reaches the halfway mark in its four-year tour of the Saturn system, discoveries made during the first half of the mission have scientists revved up to find out what's in store for the second act. See
g Aftermath - Here’s an interesting book for some astrobiological reading: “After Contact: The Human Response to Extraterrestrial Life”by Albert A. Harrison. See
for some reviews.