Extrasolar Planet Could Harbor Life

BlueMorpho writes with a link to a Space.com article about a recently discovered extrasolar planet that may be able to harbor 'life as we know it.' Orbiting around the star Gliese 581 is a small rocky ball that might have the same liquid ocean and drifting continent configuration we're familiar with. The find may be unique in all of space exploration as this planet appears to be within a habitable band of temperatures for life, and is categorically not a gas giant. "The bottom line is exciting ...The conditions for life could be there, but is life itself? As yet, there's no way to know unless the planet has spawned beings that are at least as clever as we are. As part of the SETI Institute's Project Phoenix, we twice aimed large antennas in the direction of Gliese 581, hoping to pick up a signal that would bespeak technology ... Neither search turned up a signal."

Comments

Re:Space/Genetic Exploration

[RsG]

It's not terribly likely that alien pathogens could harm us. Remember that most plain old fashioned terrestrial diseases are only able to infect a limited variety of hosts. HIV originated in chimps (our closest living evolutionary relatives), rabies is limited to mammals, the flu (which is versatile by viral standards) is primarily limited to mammals and birds, etc. Even diseases like malaria which spend parts of their life cycle in very different hosts (us and mosquitoes) are fairly specialized.

Try and imagine dutch elm disease making the transition from trees to humans. Then remember that both host organisms are terrestrial - we're more closely related to trees than we would be to any alien. It's not totally impossible that some alien bacteria could, by some chance, find the human body hospitable (or vice versa), but it isn't very probable.

Plus, the human immune system has a habit of attacking anything remotely foreign. That's why you get problems like allergies and organ rejection. If an alien organism is enough like us to pose an infection risk, then it's also most likely similar enough to trigger an immune response. And the diseases that we face today have had millions of years of evolution to prepare them for our immune system, whereas anything alien has not. So even if life elsewhere is very much like life here, it'll have the same catching up to do that we will. Admittedly pathogens evolve faster than their hosts, but then again these hosts have medical technology to make up the difference.