Saturday, November 18, 2006

Dark energy’s history, extraterrestrial messenger probe and creating believable aliens via scientific laws

Welcome! “Alien Life” tracks the latest discoveries and thoughts in the various elements of the famous Drake Equation. You may notice that this and future entries are shorter than usual; Career, family and book deal commitments have forced me to cut back some of my projects. Now, here’s today’s news:
g Stars - Scientists now have evidence that dark energy has been around for most of the universe's history. Using NASA’s Hubble Space Telescope, researchers measured the expansion of the universe 9 billion years ago based on 23 of the most distant supernovae ever detected. See http://www.space.com/scienceastronomy/
061116_darkenergy_infantuniverse.html
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g Life - Countering the widespread view of evolution as a process played out over the course of eons, evolutionary biologists have shown that natural selection can turn on a dime - within months - as a population's needs change. In a study of island lizards exposed to a new predator, the scientists found that natural selection dramatically changed direction over a very short time, within a single generation, favoring first longer and then shorter hind legs. See http://www.sciencedaily.com/releases/2006/11/061117124514.htm.
g Message - How might we detect an extraterrestrial messenger probe already in the solar system? See http://www.rfreitas.com/Astro/WhereAreThey1983.htm. Note: This article is from 1983.
g Imagining - Here’s an interesting tip sheet from the Science Fiction Writers of America about how to create believable aliens via scientific laws: http://www.sff.net/people/mmolvray/aliens.htm.
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, at http://adsabs.harvard.edu//full/seri/ASPC./0074//0000499.000.
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. Note: This article dates from 1995.