Thursday, December 22, 2011

"Only a Theory," and My Favorite Debunked Idea

If I had a nickel for every time I heard the phrase "only a theory..." well, I suppose I'd be on my way to having a good collection of nickels.  I might even have enough for a cup of coffee.  Am I right?

(The above is one of the many downsides to always wanting to be technically correct, but I'm going to get back on track now.)

"Only a theory" is pretty much the same as saying "only everything we know."  A theory, despite the colloquial definition, is not just some idea you had lying awake at night.  Theories are amassed from vast amounts of information, all pieced together into one model that explains everything.  And I mean everything.

If you look at the theory of gravity, or universal gravitation, the reason it was so amazing was that it connected the rules governing objects falling toward the Earth, and the rules governing the orbits of planets around the sun.  Nobody before Newton had ever connected those two phenomena, but many had tried to explain one or the other separately.  The problem was, without looking at the whole picture, a satisfactory answer was impossible.

So, let's be clear right now.  In scientific terms, a theory is a model that explains all the information we have, but is impossible to directly observe.  A hypothesis is an untested idea that, through research or experimentation, could be proved, disproved, or become a theory of its own (if it fits all the data yet is impossible to directly observe).  A hypothesis that does not fit the data is discarded, and a hypothesis that fits some of the data, but not all of it, is probably waiting for a better one to come around.

A current model of atmospheric electric currents.

An outdated model of atmospheric electric currents.

Tuesday, December 6, 2011

Extra-solar planets and you

I love that I live in this age of planet discovery.  In 1992, the first planet (or dwarf planet, minor planet, or Trans-Neptunian Object) in Pluto's neighborhood (besides Pluto itself, discovered in 1930) was discovered, and since then there are now more than 1200 on record, including Eris, Makemake, Haumea, Sedna, Orcus, and Quaoar.

Love those names.

Outside our solar system, planets are being discovered at record speeds by the orbiting Kepler telescope, which is watching about 150,000 stars and waiting for the amount of light they give off to dip.  The dip could be for a variety of reasons, but if it dips again, there might be a planet passing by in its orbit.  And if the light dips again, after the same amount of time has passed, you've found a planet for sure.  And if you know how big and bright the star is (which you can determine from its light spectra), you know how much light the planet is blocking, and therefore how big it is.

Some of the first planets discovered outside our solar system were discovered with similar techniques.  Watch a star, see if it dims, and see if it dims with regularity.  The other method involved careful measurements of the stars position, and seeing if it moved side to side with regularity.  That would indicate a planet's pull on its star, tugging it around as it orbits.  Both methods began rudimentarily, only detecting the biggest gas giants orbiting closer to their suns than Mercury to ours.  These are commonly known as "sun-grazers."  And when you're looking for Earth-like planets, you have to keep looking.

This is all prelude to the big news.  So far, Kepler (the satellite, not the long-dead astronomer) has discovered 708 confirmed planets (at least three passes) and over 2,000 planet candidates (only two passes so far).  These results were announced yesterday, and one of those 708 confirmed planets had some interesting features...

Monday, December 5, 2011

A Personal Update and a Holiday Science Book List

It's 10:47 AM, Monday, December 5th, and I'm sitting in my apartment in Albuquerque, New Mexico as a bitterly cold wind gusts dusty snow everywhere outside.  I have the day off today, but my wife is at work, and my Internet connection is acting dodgy at best.  I have my coffee, but my usual distractions are failing me right now.  It appears the universe is telling me it's time to update.

For the past couple months, I've been settling into a new routine of waking up late, going to work late, and coming home late.  My current job is the least enjoyable I've ever had, and I don't mind saying so, as I'll probably be leaving it soon.  In fact, I think I used to have nightmares about needing to take a job at a call center, and here I am.  (I was told it would be mainly email correspondence, which I think I would have enjoyed if it had turned out to be true.)