Saturday, January 03, 2004
In search of a slice of life
While U.S. astronomers anxiously await tomorrow's scheduled arrival of their latest probe to search for life on Mars, a study by Australian scientists is casting new light on where to look for advanced life elsewhere in our galaxy.
Their analysis argues that a slice of the Milky Way, including the region around Earth, is a "Goldilocks zone" for life to evolve. "That is, it is not too hot and not too cold; it is just right," jokes Charles Lineweaver, lead author of the study, which appears today in the journal Science.
If the analysis is correct, life in many places could have been evolving for a billion years longer than on Earth.
What the Australian astronomers and physicists did is to look for four physical features they believe are necessary for advanced life to evolve:
There must be enough heavy elements -- notably carbon, oxygen and nitrogen -- to build Earth-like life forms.
Conversely, there cannot be too much of these heavy elements, because they would produce a large number of Jupiter-sized planets. Recent analysis of extraterrestrial planetary systems suggests that the movements of these giant bodies toward their suns would obliterate all Earth-type planets in their path. Full Article>>>
Their analysis argues that a slice of the Milky Way, including the region around Earth, is a "Goldilocks zone" for life to evolve. "That is, it is not too hot and not too cold; it is just right," jokes Charles Lineweaver, lead author of the study, which appears today in the journal Science.
If the analysis is correct, life in many places could have been evolving for a billion years longer than on Earth.
What the Australian astronomers and physicists did is to look for four physical features they believe are necessary for advanced life to evolve:
There must be enough heavy elements -- notably carbon, oxygen and nitrogen -- to build Earth-like life forms.
Conversely, there cannot be too much of these heavy elements, because they would produce a large number of Jupiter-sized planets. Recent analysis of extraterrestrial planetary systems suggests that the movements of these giant bodies toward their suns would obliterate all Earth-type planets in their path. Full Article>>>
