A time-worn joke about humans is that we’re nothing more than water’s way of getting from one place to another. What if living things in general began as just another of nature’s ways of moving energy from one place to another? (Or more precisely, of minimizing energy differences by increasing energy flows from one part of their environment to another.) This article fromPhysOrg.com describes the work of a father-son team of Finnish scientists whose investigations into why life began blur the line between animate and inanimate matter.
Their recent paper in the International Journal of Astrobiology describes living processes as being simply one of the mechanisms by which entropy increases. Seen from a thermodynamic point of view, all the cool complexity that characterizes the natural world and that fascinates us is perhaps simply a byproduct, but, as with so many human behavioral and emotional phenomena, it’s quite a fascinating by-product. [Annila, Arto and Annila, Erkki, Why Did Life Emerge?, International Journal of Astrobiology 7 (3 & 4):293–300 (2008), available from arxiv.org]
While you’re pondering that, consider also some fascinating new bits of information about the possibility of life elsewhere in the universe. First, we have news from Hubble about the discovery of carbon dioxide in the atmosphere of a roughly Jupiter-sized planet orbiting another star (a planet where methane and water vapor have already been identified in the atmosphere). Although this particular planet is too hot to support life, this finding is an encouraging indicator of our growing ability to detect specific life-related molecules in the atmospheres of distant planets.
And, in a striking observational feat, a group of astronomers has been able to measure the size of an extrasolar planet using an extremely sensitive new detector. The news is summarized in this ScienceDaily article; the paper is available from arXiv.org. The camera, which can detect minute changes in the brightness of a star, imaged the transit of the planet across the star’s surface (like what we saw with the sun and Venus in 2004). From the resulting (tiny) drop in the star’s brightness as the planet progressed across its surface, the astronomers were able to determine the planet’s size, finding that it is smaller than previously estimated and in fact is one of the denser extrasolar planets found so far. Again, this new capability bodes well for the future.
Out of curiosity, how do they know how big the star is? There’s a relationship between spectrum & size (Hertzsprung-Russell diagram, right?), but I’d’ve guessed that this wasn’t a tight enough correlation to give much accuracy, and I’m not sure off the top of my head what else you’d have to go on in estimating size of distant stars.