Dark energy, habitable planet sizes and ‘Vital Dust’

Welcome! “Alien Life” tracks the latest discoveries and thoughts in the various elements of the famous Drake Equation. Today’s news:
g Stars - For centuries, humans have looked to the heavens for their gods and goddesses and clues for finding the nature of the universe. Now, the largest ever-produced map of the universe gives those lost in the dark some direction, but is also confirms that the universe is full of dark energy, a strange force pushing galaxies apart at ever faster speeds. See http://www.space.com/scienceastronomy/060515_map_heavens.html.
g Abodes - A moon or planet with about 10 percent the Earth's mass has enough gravity to retain water vapor and other gases in a temperate atmosphere (As a counterexample, Venus has enough gravity but is much too hot to retain water - the speed of water molecules in the atmosphere exceeds the escape velocity of the planet.). Mars-sized or larger moons may therefore be able to sustain both atmosphere and liquid water, if their host planet is not too far from the star. See http://www.physorg.com/news65376545.html.
g Life - Book Alert: “Vital Dust: Life as a Cosmic Imperative,” by C. De Duve is about the history of life on Earth -- from its birth, shrouded in the depths of the past, to the variegated pageantry of living beings that cover our planet today. It is the most extraordinary adventure in the known universe, an adventure that has produced a species capable of influencing in decisive fashion the future unfolding of the natural process by which it was born. See http://www.questia.com/PM.qst?a=o&d=6991411.
g Intelligence - Several scientific studies have determined that light on the eye’s retina is the primary synchronizer of human circadian rhythms, the biological cycles that repeat approximately every 24 hours. Both the visual system and the circadian system respond to light as it is processed through photoreceptors in the retina. Similar light sources can have similar effects on each system, but recent research demonstrates that similar light sources can also affect each system very differently. See http://www.sciencedaily.com/releases/2006/04/060425015333.htm.
g Cosmicus - To get a feel for why using solar energy delivered from space is a good idea it helps if you use a little imagination and envisage where it will lead - the world humans will live in when solar power satellites are a major energy source. Then it's easier to understand why it would obviously be a good direction for technological development to aim at today - instead of being almost completely ignored! See http://www.spacefuture.com/power/business.shtml.
g Learning - There are some great teacher resources on space biology at http://www.spacebio.net/modules/index.html. The modules cover such topics as “Life in the Universe,” “Radiation Biology” and “Life in Space Environments.” Each module includes an introduction, readings and references, teaching resources and research and applications.
g Imagining - Like first contact stories? Then be sure to read Murray Leinster’s short story "Nobody Saw The Ship," anthologized in “The Big Book of Science Fiction,” edited by Groff Conklin and published by Crown in 1950.
g Aftermath - Add one more worry to the computerized world of the 21st century. Could a signal from the stars broadcast by an alien intelligence also carry harmful information, in the spirit of a computer virus? Could star folk launch a "disinformation" campaign -- one that covers up aspects of their culture? Perhaps they might even mask the "real" intent of dispatching a message to other civilizations scattered throughout the Cosmos. See http://www.space.com/scienceastronomy/space_hackers_031111.html. Note: This article is from 2003.