A False Alarm on ET

News conferences, be they political or otherwise, tend to be rather dull affairs. With this fact in mind, we can't fault NASA for the 24 hours of media-fueled (read Fox News Channel, et al) hype surrounding this afternoon's announcement that a team of NASA-funded researchers had found conclusive proof of what had been previously thought to be impossible: a life form that did not use the element phosphorus to produce the chemical energy necessary for its survival.

In a paper to be published concurrently in the journal Science , a team headed by NASA Research Fellow Felisa Wolfe-Simon describe their discovery of a bacterium that is only found along the shoreline of California's Lake Mono. In this bacterium, an obscure member of the Halomonadaceae family, the element phosphorus has been replaced by arsenic. This discovery is significant for several reasons.

Of greatest significance is the fact that, although arsenic and phosphorus can have identical chemical reactivity (because of the number of valence electrons in their atoms), phosphorus-based compounds are more efficient energy producers on a mass to mass basis. It had been previously thought that, since arsenic-based compounds were less efficient at energy production, organic life could have formed only around the more efficient phosphorus compounds.

Today's announcement proves nothing regarding the possibility of life at other locations than Earth but, rather, that the phosphorus-only hypothesis must be reconsidered. In the words of some unknown, but often quoted, newspaper editor "It was a good story until the facts got in the way."

Of far more importance to the question of life in solar systems other than our own is a study originating from the European Southern Observatory (ESO) and reported in today's online edition of the Christian Science Monitor .

Astronomers working at the ESO have announced that, due to a previous lack of suitable equipment, they had drastically underestimated (by up to 100 trillion ) the actual number of a particular type of star known as a "Red dwarf." Red dwarfs have a mass of less than one half of our sun and, due to their relatively cool surface temperature of about 4000 º Kelvin (~ 6800 - 7000 º F ) are both small and dim and thus very difficult to detect from earth-based observatories. However, newer technology such as the Chandra X-Ray Observatory and the Hubble Space Telescope have demonstrated these small stars are much more abundant than previously thought. Since recent observations have demonstrated the existence of Earth-like planets orbiting red dwarf stars, and today's announcement from NASA, the probability of life in other, distant, solar systems is far greater than previously thought.