Science Friday

Today's New York Times carries an interesting feature about the $250 million EarthScope project -- and, in particular, its San Andreas Fault Observatory at Depth (SAFOD) component, which is drilling an observation hole to directly sample a seismically active fault zone. The drilling site, near Parkfield, was chosen because of its abundant microearthquake activity, and the researchers will be studying everything they can, right down to the helium isotopes in the cuttings, in the hope of gaining more insight into the earthquake process. (Though they claim they're not looking for a way to predict earthquakes, says the Times, the hope of advancing earthquake prediction "has been one of the biggest unspoken expectations since a test hole was drilled here two years ago.")

A team of researchers at the Howard Hughes Medical Institute, Harvard, and Caltech have put forth, in this week's Science, a new model for one of the more puzzling steps in the dawn of life: the creation, and evolution, of self-replicating, membrane-bound units -- that is, cells. In the past, most workers have assumed that cells evolved when primitive genetic material (probably RNA) started driving active synthesis of cell membranes. But Chen et al., performing experiments with artificial sacs of fatty acids, found that when RNA is encapsulated in fatty acid vesicles, it exerts an osmotic pressure on the membrane that drives it to scavange additional membrane from other, "relaxed" vesicles. Result: Fatty-acid "bubbles" that happened to contain bits of efficiently replicating RNA would grow faster than other vesicles, "leading to the emergence of Darwinian evolution at the cellular level." Most interesting. The abstract of the article is free with registration; you can also read more on Science Blog.

Another Science paper you'll be seeing a lot of in the next few days is the finding, published online (registration required for abstract), that the East Asian avian influenza A virus (the "Bird Flu") can infect ordinary cats -- which subsequently might be able to transmit the virus to humans (or, in the more neutral language of the report, which "may play a role in the epidemiology of this virus"). New Scientist writes up the report and its implications.

Also on New Scientist: The Search for Extraterrestrial Intelligence (SETI) project has apparently picked up "the best candidate yet for a contact by intelligent aliens in the nearly six-year history of the SETI@home project," the celebrated distributed-computing venture that harnesses the power of millions of ordinary users' PCs to analyze the signals received through SETI's radio telescope. Don't get too excited, however: The researchers still haven't been able to rule out the possibility that the signal is a previously unknown astronomical phenomenon, instrument problems, or even fraud by a renegade SETI@home user.

And, in any event, a new paper in Nature argues that extraterrestrials seeking to communicate with us would find it much more efficient to use "inscribed matter" (i.e., written docs) -- the old message-in-a-bottle approach -- than radio waves. "[O]ur initial contact with extraterrestrial civilizations," write the article's authors, "may be more likely to occur through physical artefacts . . . than via electromagnetic communication." In the related story on news@nature.com, SETI's Jill Tarter acknowledges that "We should look for artifacts of all kinds in our local neighbourhood, including packages on our doorstep" -- but also adds that, in terms of best bets, she's "sticking with radio."

That's all for now.