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 secondhandscience@gmail.com with comments, suggestions or wacky cold fusion ideas. Cheers!

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

Fast radio burst: and you thought Sex Pistols songs were short and confusing.
“Fast radio burst: and you thought Sex Pistols songs were short and confusing.”

If you’re like Fox Mulder, you believe the truth is out there.

That’s great and all, but what happens if you’re not fast enough to read it when “the truth” finally whizzes by?

That’s the sort of problem astronomers have faced since 2006, when the first “fast radio burst” (or FRB) was detected in radio telescope data recorded five years earlier. Poring over archived pulsar survey data, they found a brief spike in the signal across a range of wavelengths. It lasted less than five milliseconds, quick as a Ruby Rhod *bzzzzzz*. And then it was gone.

That may seem weird. But pulsar-hunting astronomers are used to this sort of now-you-see-it, now-you-don’t radio signal Whack-a-Mole. Pulsars are rapidly spinning neutron stars that emit radio signals, and their twirling makes the detectable signal come and go at regular intervals. Only with this particular fast radio burst, it came once… and it never came back.

Kind of like Jesus. Or Nelson Muntz’s dad.

Oh, no, wait. Nelson’s dad did come back eventually. Scratch him.

That was just the beginning of the mystery, though. The spread of the signal across wavelengths suggested that this fast radio burst had traveled across space and through interstellar gas, which can spread signal out, the way a prism does with light. Based on the spread, astronomers calculated that the signal had come from more than five billion light years away. Which meant whatever had created it must have been ginormously powerful, for the signal to make it so far through the cosmos.

That opened up a whole new can of WTFs. So far as we can tell — meaning as far as we can see with our various telescoping gadgets — there’s nothing in the region where the fast radio burst came from. No stars. No black holes. No outposts with Marvin the Martian plotting our destruction. Nada. If there’s something — or somethings — there, we’re not able to see it with our equipment. And we have no idea why it would scream at volume 11 for an instant, and then stop seemingly forever.

I mean, sure — Obi-Wan would tell you it was Alderaan. But what does he know? He doesn’t have an astrophysics degree.

The first fast radio burst was weird enough to make people skeptical. When we didn’t see another one for a few years — and when one team discovered they could make similar signals by opening a microwave door just right — astronomers wondered whether it was a technical glitch. Flying bird farts. Space voodoo. Something.

But in the past few years, ten more fast radio bursts have been detected. Now, there’s corroboration from a second radio telescope — and the last one, in 2014, was detected live as it happened. Now, scientists calculate that if we could point radio telescopes at the entire sky, full-time, we’d see hundreds — maybe even ten thousand — of these fast radio bursts per day.

That still doesn’t tell us what causes them — but there are some pretty cool theories. Each source is calculated to be no more than a few hundred kilometers wide, so these big (and quick) things are coming from some pretty celestially small packages. Some think it might be colliding black holes, or neutron stars collapsing together. Or black holes exploding, if that can even happen. Others blame them on blitzars — though why we have to bring Santa’s reindeer into this, I don’t know. We’re trying to do real science over here.

Whatever it is making fast radio bursts, astronomers are now agreed that they exist and are doggedly looking for more. Someday, with enough evidence, no doubt they’ll finally find “the truth” behind these weird astronomical aberrations.

Or they’ll find the Death Star. And I’m pretty sure Mulder wasn’t looking for that.

Image sources: PBS (fast radio burst [artist’s rendition, apparently]), QuickMeme (truthy Fox), Simpsons Wiki (Nelson and papa, haw haw!), Giant Bomb (Alderaan, we hardly knew ye)

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· Categories: Biology
What I’ve Learned:

Laser capture microdissection: the best use of lasers this side of the Death Star.
“Laser capture microdissection: the best use of lasers this side of the Death Star.”

The problem with biology is, it’s messy.

You can open up some animal or person — well, not you, necessarily, but a surgeon or researcher with explicit permission, which is kind of important — and pluck out something you’re interested in. A tumor that needs diagnosis, say. Or a part of the brain not behaving itself. Maybe a gall bladder, because it’s infected or malignant or the doctor has a really weird Pandora bracelet thing going on.

It’s all well and good to decide what you want to carve out. But that’s where biology goes and gets messy.

Take the tumor example. Tumors don’t ordinarily grow in nice neat little balls inside the body, just waiting to be sliced away and stored in formaldehyde or used in a macabre match of bocce. Instead, they ooze between other tissues. They spread tendrils through organs and hop from one body part to another, like some kind of inner-space kudzu. To cut out the tumor, you’ve got to cut other stuff, too. And it’s not always clear which bits are which until the globs of flesh are sliced thin, slapped on microscope slides and diagnosed by a pathologist.

Even normal tissues have the same problem. Say you’re a brain researcher, because you’re a smart cookie and a Futurama fan and you don’t want to rely on Philip J. Fry to save the universe some day. That’s kind of a weird path to a career choice, but hey, it’s your life. Who am I to judge?

Anyway, you might want to study neurons pulled from the brains of lab mice or rats. But in that same brain sample are cells of other types. Glial cells. Skull cells, if you’re a little careless with the scalpel. Liver cells, if you’re a lot careless. The point is, to identify the neurons — and just the neurons — you’ll probably have to slice the tissue up, make some slides and find them under the microscope.

The question is: then what?

For decades, scientists could go through the procedures above and figure out that this sample over here was thirty percent pure for the cells they wanted, and that sample over there was ninety percent pure. But if they wanted to study those cells — pull out DNA or RNA or proteins and see what made them tick — they had no way to get rid of the contaminating schmutz scattered around them.

That’s where laser capture microdissection, or LCM, comes in. It sounds like something Darth Vader might do to torture information out of a Wookie, but it’s not. It’s actually more of a way to get rid of blemishes and impurities in a biological sample. Like an Oil of Olay for microscope slides.

So how many scientists does it take to perform a laser capture microdissection? Three, in principle. First, some smart brave person hooks an ultraviolet or infrared laser to the controls of a microscope, so moving the field of view back and forth will burn a line through the sample. Then a very patient careful person stares into the microscope for an hour or two, twisting the controls like an ungodly-expensive Etch-A-Sketch, tracing around the parts of the sample they want to carve out.

Finally, some brilliant crazy person figures out how to get that laser-jigsawed piece off the slide to do more science. Current methods include melting wax and sticking it to the piece (fairly awesome) to using gravity to shake the piece away (more awesome) to something called a laser pressure catapult (ridiculously awesome). This last procedure involves shooting an unfocused laser at the sample, literally punching the cutout into the air with photon force. Which, again: Wookie torture. But no. Science.

So that’s laser capture microdissection. You get just the bits you want, and none of the bits you don’t. And then you can look at just the cells you like, without anything else getting in the way. It’s as easy as Photoshopping George Costanza out of a vacation pic.

Just don’t try it on a Wookie. That would not end well.

Image sources: University of Gothenburg (laser capture microdissection), ikdoeict.be (Fry and the brains), Hurtin Bombs (angry Chewy, vengeful Chewy, purr purr purr), Woosk (Costanza photobomb)

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