Wednesday, July 18, 2007

Collecting Martian soil samples, water in M dwarf’s habitable zones and nuts-and-bolts walkthrough of SETI

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 Abodes - A new paper by Jack Lissauer (NASA Ames) argues that planets inside an M dwarf’s habitable zone are probably lacking in water and other volatiles, and are thus unable to produce life as we know it. See
g Message -Would anyone deliberately beam high-powered signals into space? Can we assume that extraterrestrial societies would broadcast in ways that would mark their location as plainly as a flag on a golf green? See
g Cosmicus - NASA's Phoenix lander is designed to land on Mars and dig into the planet's subsurface to collect ice and soil samples. Researchers are now making sure that exhaust plumes during the craft's arrival on Mars will not complicate the lander's ability to collect and test its samples. See
g Learning -Here’s a neat classroom activity: “Designer Genes for a Designer World.” In this series of guided inquiry activities, students explore how organisms adapt to their environments through changes in their genetic codes. See
g Imagining -Among the more famous alien races from “Star Trek” are the Gorn, bipedal reptilians who are much larger and stronger than humans (for picture, see
). The Gorn are an unlikely alien species but a splendid example of how we so often portray extraterrestrials based not on scientific principles but our own psychology — like the insect alien, most humans naturally find the reptilian alien repulsive. For science fiction, it’s a good choice to create suspense: creatures out of our nightmares that we keep going back to out of a fascination over what frightens us. But could the Gorn evolve on another world? Probably not. The most troubling feature of the Gorn is the remarkable parallel evolution that would have to occur on Gorn Prime to Earth for a few billion years, at least up to our Age of Dinosaurs. Also disconcerting is the Gorn’s snout; this adds weight to the head and with a large brain size creates excessive and unbalanced weight for the neck muscles to hold up. Another problem is the Gorn’s slow movements; certainly a species that evolved to intelligence would have to move a little faster, or it could not succeed in hunting. A caveat here is that its lack of agility may in part have propelled it to intelligence, as it needed to outthink faster moving prey. Some “Star Trek” fans have speculated that Gorn Prime possesses a harsh environment and a relatively high local gravity (1.4 Gs!), which accounts for the Gorn’s increased strength and endurance levels. This seems unlikely, though, as the Gorn then would be able to move swiftly on the asteroid presented in the episode, which Kirk shifts about on as if it were Earth normal gravity.
g Aftermath -Book alert: As many Earthlings already know —including more than 2 million computer users with firsthand experience — our best hope for finding extraterrestrial intelligence might just lie with an ingenious little screensaver. So it's not surprising that “Beyond Contact: A Guide to SETI and Communicating with Alien Civilizations” (by Brian S. McConnell), an introduction to searching for and communicating with intelligent life, begins with some of the details behind UC Berkeley's groundbreaking, massively distributed SETI@home project, which processes intergalactic noise for pennies on the teraflop. But that's just the start of the story. Inventor and software developer Brian McConnell continues with an overview of whether and why we might find something out there, who's doing what to look for it (including the folks at Berkeley), and — once some ET picks up on the other end — what we might say and how we might say it. This last problem, which occupies the final half of the book, proves to be the most thought provoking, and McConnell has put together a methodical, nuts-and-bolts walkthrough of both the challenges involved and how binary code might be enlisted to solve them. For reviews, see