Thursday, July 30, 2009

Grains reveal solar system’s earliest history and ‘The Consequences of Discovery’

Welcome! "Alien Life" tracks the latest discoveries and thoughts in the various elements of the famous Drake Equation. Here's today's news:
g Stars - Like messages in a bottle, grains inside meteorites carry clues to the history of our solar system. Some of these tiny crystals are older than the solar system itself. A new study has determined the age of a set of grains from one meteorite. The results seem to indicate a galactic disturbance may have triggered the formation of our solar system. See article.
g Abodes - Iron and manganese compounds, in addition to sulfate, may play an important role in converting methane to carbon dioxide and eventually carbonates in the Earth's oceans, according to a team of researchers looking at anaerobic sediments. These same compounds may have been key to methane reduction in the early, oxygenless days of the planet's atmosphere. See article.
g Life - When we think of extrasolar Earth-like planets, the first tendency is to imagine weird creatures like Jar Jar Binks, Chewbacca, and, if those are not bizarre enough, maybe even the pointy-eared Vulcan, Spock, of Star Trek fame. But scientists seeking clues to life on extrasolar planets are studying various biosignatures found in the light spectrum leaking out to Earth to speculate on something more basic and essential. See article.
g Intelligence - Putative extraterrestrial planets are being discovered at the rate of one a month. A subset of these exist in the liquid water zone and are thus capable of evolving life similar to that with which we are familiar. While perhaps not common, the development of technological civilizations seems possible for some of these worlds. If we are typical, the evolution of technological civilizations proceeds from a condition where physical laws are unknown to a state where the limits imposed by those laws are reached within a few hundred years. These limits (molecular nanotechnology on solar system scales) allow the construction of Dyson shell supercomputers ("Matrioshka Brains') with thought capacities a trillion trillion times greater than that of a human brain and longevities measured in billions to trillions of years. Natural selection at stellar and galactic scales would, over time, eliminate any civilizations lacking these prodigious capabilities. We must consider that astronomical observations such as the missing baryonic dark matter and the gravitational microlensing observations may indicate that many such entities exist and that our galaxy is currently a Kardashev Type III civilization. See article.
g Cosmicus - Long-duration travel in space has many ill-effects for humans, including muscle and bone loss. Some scientists believe that astronauts on a mission to Mars could suffer loss of muscle so severe that they would be unable to walk upon their return to Earth. However, new research may provide a solution that will keep future explorers safe and healthy. See article.
g Learning - Here’s a neat classroom activity courtesy of NASA: “Interstellar Real Estate”. The lesson examines what makes Earth the perfect home for life as we know it as students explore the orbital characteristics a planetary home needs to support Earth-like life forms.
g Aftermath - Here’s an intriguing article that is frequently referenced in astrobiology papers: “"The Consequences of a Discovery: Different Scenarios" by astronomer Ivan Almar. Warning: it dates from 1995.

Get your SF book manuscript edited


Honoring the Past, Inspiring the Future

No comments: