Do you remember the movie Avatar?  Do you remember the precious metal the humans were mining for?  They called it unobtainium, which is the stupidest name any precious metal could have.  I mean… you’re never going to obtain it!

But lately I’ve been studying the periodic table of elements, and it turns out there are a bunch of elements with names like ununseptium or ununoctium.  And scientists are searching for elements 119 and 120, to be named ununennium and unbinilium.

Suddenly, the name unobtainium seems almost believable.  Then I did a little more research, and to my surprise found that unobtainium is a real thing!  Or at least a real term.

When scientists or engineers need a special material with specific properties, but the material does not exist, they call it unobtainium.  It’s the stuff that will magically solve whatever problem they’re working on.  They name is a placeholder until the required material is discovered or invented.

Science if full of stupid and inaccurate names, but once people get used to those names it’s hard to change them.  Planetary nebulae have nothing to do with planets.  Gluons and glueballs have nothing to do with glue.  Maybe Avatar’s unobtainium is another example.  They discovered a material that fit some specific purpose (like levitating mountains), and the placeholder name stuck.

Tomorrow, Mass Effect’s Element Zero.

Here are this week’s sciency links.

• At Long Last, Gravity Probe B Proves Einstein Right from Science Magazine.  Turns out pi doesn’t always equal 3.141592…
• Abell 2218: A Galaxy Cluster Lens from Astronomy Picture of the Day.  This picture shows further proof of Einstein’s theory.
• Building Curiosity: Going for a Spin from NASA’s Jet Propulsion Laboratory.  Work continues on a new Mars rover.
• Northern Fur Seal Release from the Island Wildlife Natural Care Centre.  It’s really cute.
• Calculating the Elements of Life from Photonist.  Why is there so much carbon in the universe when certain lighter elements are so rare?
• Bring Science Home from Scientific American.  Simple science experiments anyone can do.

Awhile back, my friend’s cat interrupted me while I was writing a story about quantum mechanics.  I think I know why.

Quantum mechanics is a difficult subject, full of rules that defy common sense.  A scientist named Erwin Schrödinger proposed a thought experiment to help explain it.

You put a cat in a box with a small device that will either release a deadly poison, killing the cat, or do nothing at all, sparing its life.  The cat has a 50-50 chance of surviving the experiment, but until someone opens the box both possible outcomes exist simultaneously.  The cat is both alive and dead at the same time.

As odd as this seems in the real world of cats and boxes, it is true of atoms and subatomic particles.  They exist in all possible positions, doing all the things they could be doing, until someone observes them.

This is the reason my friend’s cat interrupted my writing.  He was concerned that, since no one was observing him, he might turn out to be dead.  That’s why cats crave attention so much.  They understand quantum mechanics… maybe better than we do.

P.S.: I don’t know much about Erwin Schrödinger, but I really hope he didn’t own any cats.

The next few years may brings us spectacular new discoveries about antimatter.  CERN has gone from creating a few dozen atoms of anti-hydrogen at a time to making hundreds, and the Space Shuttle Endeavor will soon deliver a new antimatter and dark matter detector to the International Space Station.

Here are some articles that try to predict what we might learn.

• CERN makes 309 anti-hydrogen atoms.
• The Alpha Magnetic Spectrometer (AMS): looking for antimatter in space.
• NASA’s mission summary for Shuttle Endeavor’s last mission (pdf file).
• Would antimatter give us antigravity?
• Get news about the AMS on Twitter by following @astroparticle or @ams_02

Normally on this blog, I try to share some interesting new thing I’ve learned about science.  Today, I have a question.  Why do kids love dinosaurs?  The answer might give us a clue about how to get kids interested in science.

My guess is that kids like words that end in -est.  Biggest, tallest, strongest…  Maybe it has something to do with being so little.  Maybe kids admire dinosaurs because they want to grow up to be the biggest, tallest, and strongest themselves.

Picture courtesy of wpclipart.com

When I was a kid, my favorite dinosaur was the Plesiosaurus.  It had flippers instead of feet, and in my mind that made it the weirdest.  I’m not sure what that says about me.

Anyway, what’s your theory?  Why do you think children love dinosaurs?

I’m stealing an idea from fellow blogger Jon Gibbs.  Every Friday on his blog, An Englishman in New Jersey, he posts links to some interesting blog posts about writing.  So starting today, every Friday I’ll post some links to interesting articles (or other things) about science.

• Does Quantum Mechanics prove we have free will?
• The Earthquake in Japan shifted the Earth’s axis by about 6 inches.  How does that affect our weather?
• City pigeons: are they smarter than you think?
• Who’s the better rap artist: Albert Einstein or Stephen Hawking?
• Vote for the best spaceship of all time.

Please leave a comment if you enjoy any of today’s links.

Any science enthusiast, and probably any science fiction fan, has heard of dark matter.  80% to 90% of the matter in our universe is invisible.

You may be wondering, as I did, how we know about it if it’s invisible.  The answer is that we’ve observed it by its effects.

As Earth orbits the sun, its motion is controlled by two forces: the sun’s gravity and the Earth’s momentum (velocity).  These forces are perfectly balanced, and if Earth’s momentum were a bit higher it would escape the sun’s gravity and fly off alone into space.

In the same way, stars orbit the center of the galaxy, their momentum balanced to the center’s gravity.  Except the balance is wrong, and the stars are moving too fast.  They should fly off, yet they don’t; thus, some invisible stuff must be increasing the gravitational force of our galaxy.

There could be a simpler explanation.  Perhaps our laws of gravity are incorrect.  We’ve only studied how gravity affects falling objects, planetary orbits, and the interactions of stars.  Maybe there’s more to gravity than we can see on such small scales, and we require a galactic perspective to see our error.

As far as I know, most scientists are not ready to rewrite gravity.  Not without more evidence.  Personally, I think the existence of dark matter is easier to believe, but science fiction writers should be aware of crazy new ideas in science.  They may become the basis for a great story.

Links:

• Observations of the Bullet Cluster, a group of galaxies colliding with each other, may prove that dark matter exists.  Click here.
• Other scientists say a Modified Gravity Theory can explain the Bullet Cluster.  Click here.
• The theory of dark fluid combines dark matter with dark energy, another big, invisible part of our universe.  Click here.

I’m seeing more and more commas out of place, and not just on the internet.  Published authors don’t know how to use them right either!  Every book I read I seem to find at least one comma someplace it doesn’t need to be.  Usually a lot more than one.

The thing is, English is a living, evolving language.  If enough people keep making the same mistakes over and over, the mistakes become part of English grammar.  Just like how the definition of irony has changed because everyone (especially Alanis Morissette) used it wrong (I remember when irony only had two definitions; now dictionary.com says it has eight).

Most people assume languages become simpler as they age.  But maybe that’s not always true.  If the rules of how to use a comma get more complicated, to accommodate all the people who use them wrong, then maybe future English will be even more complicated and confusing than the English of today.

Good story telling involves overcoming obstacles.  In sci-fi, those obstacles often include aliens, robots, various anomalies in space or time…  We forget that every cubic light-year of space is full of danger even before we start making stuff up.

Pictured above: our galaxy, the Milky Way.  Part of the image is obscured.  You see those dark clouds?  That’s dust.  Cosmic dust.  Vast clouds of it—enough to block out the stars behind.  Our galaxy is a very dirty place.

If you want to travel anywhere near the speed of light, that dust becomes a huge obstacle.  A collision with a particle smaller than a grain of sand—at high enough velocity—would punch a hole through your ship.  Passing through a cloud of such particles would be like walking into a spray of bullets.

Find that hard to believe?  Think about hitting a deer.  At ten miles per hour, it’s not so bad.  At thirty-five, it’ll probably leave a dent.  At seventy, your car is lucky to be alive.  The greater the speed, the more damage the deer will do.  Now imagine hitting a deer—or anything—at the speed of light, 10 million times faster than any car can go.

With so much dust in our galaxy, the navigators of any interstellar spaceship will spend a lot of stressful hours dodging particles too small to even see.  That, combined with the cosmic radiation from yesterday’s post, makes “empty” space as dangerous as any alien, robot, or space-time anomaly.

Links:

Click here for the Iris Nebula, a place where clouds of cosmic dust are clumping together to form new stars.

Click here for some computer simulations of what cosmic dust particles look like at the molecular level.

Click here for a glossary of terms related to cosmic dust and other things found in “empty” space.

Good story telling involves overcoming obstacles.  In sci-fi, those obstacles can include aliens, robots, various anomalies in space or time…  We forget that every cubic light-year of space is full of danger even before we start making stuff up.

In addition to normal background radiation, empty space is full of other dangerous particles like high-energy helium ions (alpha particles), high-energy electrons (beta particles), and high frequency photons (gamma rays).  These particles spew out of stars constantly and often get trapped in the magnetic fields of our planet and solar system.

Despite all our technology, astronauts are exposed to that radiation every time they go into orbit; so much so that NASA has safety guidelines to limit exposure during any individual’s lifetime.

Here on Earth, we are protected by the ozone layer and Earth’s magnetosphere (and yet too much sunlight… ultra violet radiation… can still give you cancer).  Without some similar protection, any brave explorer in deep space will die a slow and un-dramatic death.  Below are links to PDF files from NASA about radiation in space.

Minimizing Space Radiation Exposure During Extra-Vehicular Activity

Radiation Exposure and Mission Strategies for Interplanetary Manned Missions

Tomorrow, we’ll look at another obstacle out there in “empty” space.