Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Astronomy, Physics
What I’ve Learned:

Albedo: upon further reflection, it keeps getting better.
“Albedo: upon further reflection, it keeps getting better.”

I used to think “albedo” was a term for sex drive in people without skin pigmentation. This led to some very uncomfortable conversations. And, as someone who doesn’t tan very well, a lot of unsuccessful pickup lines.

As it turns out, albedo means something a little bit different. It’s another word for “reflection coefficient”, which is the ratio of light reflected off an object to the amount of light pumped in. For a highly shiny object — Gwyneth Paltrow’s forehead, say — then you have a high albedo, close to 1. On a much darker surface — where light rays check in, but they don’t check out — the albedo will be very close to zero.

A partial list of substances on the low end of the albedo scale:

A 7-11 asphalt parking lot: 0.12
Charcoal: 0.04
Vantablack carbon nanotube substance: 0.00035
C. Montgomery Burns’ shriveled heart: 0.002
Black hole: 0(-ish)
Spinal Tap’s Smell the Glove album (revised cover): 0.000000001

(How much more black could it be? The scientific answer is: negligibly more black, allowing for measurement variability and prevailing experimental conditions. Nigel Tufnel wasn’t so far off.)

The albedo of most objects is affected by two things: the angle and the wavelength of light streaming in. Light glancing past is easier to reflect, and some materials have a preference for absorbing or bouncing back light of various colors.

In fact, that’s how we perceive objects as having colors; we only see the wavelengths bouncing off them that they neglected to absorb. If every substance sucked up every wavelength of light like some kind of solar paper towel, then they’d all be completely black.

Unlike non-solar paper towels, which are white. Because the Brawny man will clean up your coffee spills. But he’ll never take away your sunshine.

In astronomy, albedo is an important characteristic of faraway objects, and can be used to determine what they’re made of. One of Saturn’s moons, Enceladus, has a surface of nearly pristine ice, and an albedo of 0.99. You could basically use Enceladus as a mirror to see if there’s spinach stuck between your teeth, except that its 750 million miles from your bathroom and your face would freeze if you got anywhere close to it.

This week’s flyby — or more accurately, screamingwhooooshby — of Pluto by the New Horizons spacecraft is providing details and answers to a question first raised by albedo measurements of Pluto and its largest moon, Charon. These bodies (as well as Pluto’s other moons) are thought to have formed from a collision of two large objects many millions of years ago. But looking at light reflected from them, Pluto has an albedo in the range of 0.49 – 0.66, while Charon is much darker, at 0.36 – 0.39.

Why the difference? Are the two made of different substances, after all? Did somebody polish Pluto up to try to get it reinstated as a planet? Or is Charon just going through a “goth” phase?

These are answers that albedo alone can only hint at, for objects at the edge of our solar system and for planets many, many light years away. It’s not a perfect tool for astronomical discovery — but for the places our probes (and horny albinos) can’t reach, it’s an awfully good start.

Image sources: University of Washington (albedo spectrum), ChaCha (Gwyneth aglow), Brass Collar (“none more black”), Got a Nerdy Mind? (the Brawny menagerie)

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· Categories: Biology, Genetics
What I’ve Learned:

Optogenetics: science--invented, laser doge-approved
“With optogenetics, you won’t just ‘see the light’. You’ll feel it.”

The brain is a pain in the ass, scientifically speaking. And scientific-researchly speaking, which is probably a real thing.

Studying the brain is unusually tricky. It’s a complicated organ with billions of cells, electrical signals whizzing everywhere and neurotransmitters getting passed back and forth like the last beer at a tailgate. You want “simple”, go study an appendix. The brain is not for you.

Also, the brain comes not-so-conveniently wrapped in a hard candy shell called a skull. To reach it, you’ve got to drill through bone — and then dig through brain, if the bit you’re after is in the middle. For decades, brain science was like trying to yank grapes out of Grandma’s Jell-O without breaking the mold. As any eight-year-old can tell you, that’s damned near impossible.

Then there’s the scale. Most organs you study with a microscope, or even a camera. Drop a miniature Nikon down (or up) someone’s gut and watch a day in the life of a colon unfold in real time.

Or slower, if your test subject is a big fan of fiber.

But the brain operates at millisecond speed. Blink, and you miss a million firing synapses, lighting up the cerebellum. And the cerebrum. And that other bit — the one for remembering numbers and science facts and what parts of brains are called. Mine doesn’t work, apparently.

How can scientists possibly get around all these problems? Enter optogenetics, which allows neurocowboys a new way to put eyes on the brain. Literally. (Almost.)

The ‘opto-‘ part of the name suggests light (or eye doctors), and refers to light-sensitive proteins — like those in our eyes’ rod and cone cells — found in species like fruit flies, algae and bacteria. These proteins react to specific wavelengths of light; by snipping out the DNA sequences coding them (hence the “-genetics”) and linking them to genes in test animals, scientists can set off signals in those animals’ brains — just by turning on a flashlight.

A very special kind of laboratory flashlight. Very wavelength. Much science. Wow.

Now researchers can trigger — and measure — brain events at the speed of light. They’ve even developed wireless versions of their flashy-light and brain-detect-o-matic devices, allowing them to study animals running free in the lab. Or “free” in a cage. But not attached by the forehead to an industrial science laser. Which is nice.

The techniques are fairly new, but have already changed the neurobiology game. Among other things, scientists have used optogenetic methods to implant false memories (and sexy thoughts) in fruit flies, flip-flop social behavior in mice, relax muscles in worms, break habits in rats and kill pain (again in mice) with a flash of light. Creepy Island of Doctor Moreau vibe aside, this research could someday have important applications in human medicine. Also, with all the flashing lights and artificial mind altering, the lab animals just think they’re at tiny adorable raves.

One final measure of the impact of optogenetics: In 2010, it was named scientific “Method of the Year”. Presumably, it beat out “stash your samples on ice overnight so you can duck out for Happy Hour”. For scientists, that’s a huge upset.

Image Sources: ExtremeTech (lab mouse), Jello Mold Mistress (Jell-O mold), NoodlyTime (laser doge), Redshirt Knitting (mouse rave)

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