Size of the cosmos, delays in verifying signal from ET and radiation risk to astronauts

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 - A new discovery is casting doubt on the idea that a type of star explosion shines with equal brightness wherever it occurs in the universe. The finding could have implications for estimates of the size of the cosmos. See http://www.space.com/scienceastronomy/
060920_supernova_atypical.html.
g Life - Coral-like mounds on the floor of a Canadian lake may make it easier someday to identify life on other planets. See http://www.
astrobio.net/news/modules.phpop=modload&name=News&file=
article&sid=113. Note: This article is from 2001.
g Intelligence - Even the tiny, mild-mannered fruit fly can be a little mean sometimes – especially when there’s a choice bit of rotten fruit to fight over. And, like people, some flies have shorter tempers than others. See http://www.sciencedaily.com/releases/2006/09/060920192543.htm.
g Message - Most SETI programs scan the sky looking for strong radio signals. Any signals that are deemed interesting are put on a list for follow-up observations weeks, months — even years later. Long delays in verification of potential ET signals sometimes generate tantalizing, but ultimately frustrating, stories. See http://www.space.com/searchforlife/seti_backus_rhythm_030320.
html. Note: This article is from March 2003.
g Cosmicus - It doesn't just matter how much radiation an astronaut is exposed to; time and the order in which charged particles strike human cells are important factors as well. That's the main finding of a study simulating radiation exposure conducted at the U.S. Department of Energy's Brookhaven National Laboratory and published in the September 2006 edition of Radiation Research. In the study, human cells were three times more likely to develop properties similar to those in the initial stages of cancer when they were exposed to two types of high-energy particles in a short period of time. See http://www.astrobio.net/news/modules.phpop
=modload&name=News&file=article&sid=2067mode=thread
&order=0&thold=0. For related story, see “One-two Particle Punch Poses Greater Risk For Astronauts” at http://www.sciencedaily.com/releases/2006/08/060824222016.htm.
g Learning - Here’s a great classroom resource guide, courtesy of NASA: NAI's team at NASA Ames Research Center has created Chapter 4 of the Yellowstone Resources and Issues Guide which tells all about thermophiles, their habitats in the park, and their relationship to both the history of life on Earth, and the search for life elsewhere. The guide is used to train park naturalists and rangers, and it can also serve as a valuable resource when teaching about extremophiles and astrobiology in the classroom. Download your copy at: http://www.nps.gov/yell/publications/pdfs/handbook/ch4.pdf.
g Imagining - Like first contact stories? Then be sure to read Robert Heinlein’s novel “Have Spacesuit, Will Travel,” published by Scribners in 1958.
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.