Tuesday, March 29, 2011

What we don't know

The loose ends in science are at least as interesting to me as what we (think we) know.

Take the Higgs boson, the elusive quarry of the biggest experiment in science: the Large Hadron Collider (LHC). The Higgs boson is the remaining particle predicted by the highly successful standard model of nuclear physics -- and yet to be detected.

A very weird thing, the Higgs boson, so weird/elusive/mysterious that it's developed the nickname of "The God Particle," from the book of the same name. The Higgs boson is said to give the attribute of mass to some subatomic particles.

Tuesday, March 22, 2011

There is a tide in the affairs of spacefarers ...

Fate of Worlds is at an exciting point -- it's hard to tear myself away from working on the first draft. So: to make this a quick post, I'm sticking to a couple of keen bits of space news. (In a year or so, the Known Space fans among you will thank me.)

First, NASA recently released the highest res image ever of the entire lunar far side (a small version of which is shown at left). It's a composite image assembled from thousands of detailed images captured by the Lunar Reconnaissance Orbiter -- from an altitude of only about 30 miles! Seriously cool.

And much farther from home ...

Tuesday, March 15, 2011

Searching the solar sytem's attic

Where is everyone?

That simple question is the essence of the Fermi Paradox, posed (if only, perhaps, apocryphally) by nuclear physicist Enrico Fermi. More expansively: if life arises naturally on suitable planets, then why -- with so MANY stars around us -- hasn't intelligent life contacted or visited Earth? If aliens haven't, maybe the premise about life arising naturally and then intelligent life following naturally is suspect.

(Regular readers of this blog know that as an SF author I'm interested in the search for extraterrestrial intelligence (SETI) and in First Contact scenarios. This post is about one small aspect of the science of SETI. If you're curious about my fictional uses of SETI, check out my InterstellarNet series and Moonstruck posts.)

Traditional SETI, based on listening for radio signals, has been noticeable for its lack of success. It turns out listening isn't the only SETI option. There's a SETI offshoot called search for extraterrestrial artifacts (SETA). A subset of SETA is search for extraterrestrial vehicles (SETV). The dressed-up term for it is xenoarcheology. Like astrobiology, xenoarcheology is a science for which, to date, there is no proof of the existence of its subject matter.

Finding (or thinking one has found) physical evidence of aliens is an SF staple. Consider, for example, the black monoliths in the acclaimed 2001: A Space Odyssey. And I've always been partial to the cover at left, from James P. Hogan's Inherit the Stars.

The SETV argument goes like this. Signaling across interstellar distances takes a lot of energy.  Sending that (expensive) signal yields a benefit only if someone hears it. Sending a space probe is much more energy efficient -- albeit slower -- than beaming across the light-years. The visiting probe can gather data independent of the tech level of any creatures in the visited solar system. The probe can also choose to announce itself with a locally transmitted signal. Proponents of SETV advise us to look around our solar system for alien spacecraft.

Tuesday, March 8, 2011

Not about Charlie Sheen ...

... Except to the degree it's true of each of us.

Panspermia (from the Greek, literally "all seed") is the hypothesis that primitive life exists throughout the universe and thus that life on Earth may have originated elsewhere. Panspermia theory doesn't contradict evolution, because evolutionary theory deals with how life changes, not how (or where) it began.

Did life come to Earth on, say, a meteorite? While panspermia is not exactly the scientific mainstream, it has had prominent advocates over the centuries, including physical chemist Svante Arrhenius, physicist Lord Kelvin (aka, William Thomson), and astronomer Sir Fred Hoyle. It's commonly accepted that organic chemicals are widely dispersed in space, but there's been no proof of extraterrestrial life. (In 1996 President Clinton made a statement to announce NASA might have found fossilized bacteria in a meteorite of Martian provenance ...

but those findings were later downgraded to inconclusive.)

Now there's a new (March 5th) report: Exclusive: NASA Scientist Claims Evidence of Alien Life on Meteorite. These latest findings are from Dr. Richard B. Hoover, an astrobiologist at NASA’s Marshall Space Flight Center.  Briefly, he reports finding microstructures within a meteorite reminiscent of cyanobacteria. Ditto biochemicals.

Thursday, March 3, 2011

The winds of change

I'm often amazed at the perception that wind power is free and clean.

Not free, because the windmills/generators must:
  • be built, generally in some remote area (say, in the middle of the High Plains or miles off the coast),
  • have high-capacity transmission lines extended to them (and power lines take longer to build than the wind farms themselves),
  • have back-up power provided for them (for when the wind isn't blowing), 
  • have storage provided for them (so that power from night-time wind can be used when it's needed -- often, during the day),
  • be supported by a national grid made more robust to cope with the variability of the wind-driven power, and
  • be maintained (including those new transmission lines, storage, etc.).
Still, some say, the wind is free. It's true: in a strictly monetary sense, wind-as-fuel is free. No, if one takes into account what economists call  the "externalities." Those are costs that society bears but the asset owner does not. (In the same way, pollution from fossil fuels traditionally has been an externality for the gasoline refiner -- not so much once air-pollution-abatement controls were mandated.)

So what are some externalities of wind power?