Day: June 27, 2009

Limits of Life

Life – but not as we know it – space – 06 June 2007 – New Scientist.

The Limits of Organic Life in Planetary Systems

These two, a “New Scientist” article and a short National Academies Press book, contain some of the more interesting concepts to hit astrobiology in a very long time. They discuss, in understandably limited terms, the limits of what Life might be like without the usual requirements of water, oxygen and even organic compounds – for example, gas-phase enzyme activity, life-in-sulfuric-acid, life using methylforamide, life in super-critical CO2 and life based on silicon in cryogenic conditions.

Let’s step back a bit. A certain Ph.D in Chemistry, one I. Asimov, also had a modest career as an SF writer. A short essay by him appeared in a SETI related magazine, in which he discusses possibilities for life-as-we-don’t-know-it…

Not as We Know it

…to which we can add some more possibilities now.

All this speculation, about which I will elaborate later, does make the Fermi Paradox seem a tad lame.

Neutrino Tricksters?

Solar ghosts may haunt Earth’s radioactive atoms – 24 June 2009 – New Scientist.

Ephraim Fischbach, searcher for “Hypercharge” fifth force in the 1980s, has produced an intriguing new analysis of radioactive decay data which indicates periodicities in various decay processes that shouldn’t exist. Radioactive decay is held to be “random” – in reality probabilistic because particles tunnel out of nucleii according to what energy they can borrow from the quantum vacuum, and that’s a ‘random’ thing. In operational terms it means radioactives should decay without respecting clocks, thus ideally we shouldn’t see seasonal and shorter term variations. But, of course, we live and experiment in a variable environment that does show such changes, which means most physicists are suspicious of the new results.

Some more related news-bites…

Radioactive Decay and the Earth-Sun Distance …John Cramer’s “Alternate View” article on the work. He also covered Fischbach’s Fifth-Force work in the 1980s.

The mystery of the varying nuclear decay …PhyicsWorld wades into the issue. Quotes Fischbach to the effect that ‘decay constants’ aren’t so constant.

Half-Life (More or Less) … ScienceNews does a similar piece, covering much of the physics community’s reaction.

Implications for C-14 Dating of the Jenkins-Fischbach Effect and Possible Fluctuation of the Solar Fusion Rate …a discussion of the possible ~200 year periodicity in C-14 decay and it’s possible relationship to the “Jenkins-Fischbach effect”. Indicates that archaeological dating by C-14 is thus probably in doubt – though by how much is guess-work. 200 years?

This is very much a “watch-this-space” kind of thing. Recent analysis of “Cassini’s” RTG output, which uses Pu-238, one of the variable isotopes, shows no variability – BUT Fischbach says that maybe due to power-variations from decay being masked by power-variations due to solar variability, which matches neutrino-flux variation in the model. Thus the signals counter-act. Maybe.

Global windfarm for Poverty Living…

Prof: Global windfarm could power entire human race • The Register.

Beware of wind-farm maniacs. Sure the Earth’s winds shift a huge mass of heat energy away from zones of net radiative input around the Equator towards regions of net radiative output around the Poles, but tapping those flows is a non-trivial matter for technologists to achieve. Covering the Earth in wind turbines might be able to supply 7 billion people with a European style energy supply BUT more realistic estimates suggest they’ll need to live like the poorest of the poor to get by. Rubbery figures mean the estimates of energy potential are, at best optimistic, and at worst misleadingly directing green opinion towards infeasible alternatives to fossil-fuels. Only space-based solar and green nuclear power can really supply humanity’s legitimate energy needs in the long-term.