Sneezing in Space

March 15, 2017

So in case you were wondering: yes, astronauts do sometimes sneeze in their spacesuits. And no, there’s nothing they can do about it when it happens. The sneeze just splatters on the helmet’s faceplate.

I believe I first read about this in one of those Time Magazine specials I reviewed last year (click here or here).

The thing I really want to know is how the force of the sneeze affects the astronaut’s motion, especially when the astronaut is not wearing a helmet. For example, what happens when an astronaut is floating freely aboard the I.S.S. or some other spacecraft and suddenly sneezes?

I’d imagine the force of the sneeze could have some amusing propulsive effects in microgravity.


Sciency Words: Ecotype

December 30, 2016

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Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us expand our scientific vocabularies together. Today’s term is:

ECOTYPE

Let’s say you discover two groups of antelope. Both groups are the same species, but one group lives on the east side of a mountain range and the other group lives on the west side.

Again, these antelope are all the same species of antelope. But because of a geographic barrier, the two groups rarely if ever intermix or interbreed. As a result, one group has developed thicker wool than the other, or they have slightly different antler shapes, or there’s some other distinctive characteristic that one group has and the other doesn’t.

When you find distinctly different groups within the same species, the groups are called ecotypes. Typically, this sort of differentiation occurs within a species because ecotypes are living in separate ecological habitats.

I first encountered this term in a recent article in Scientific American. As a science terminology enthusiast, I find this to be an interesting kink in the ongoing debate over how to define the word “species”—but the article I read was about something even more interesting than that.

Orca Ecotypes

If we ever learn to communicate with orcas (killer whales), we should tell them about Shakespeare.

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Orca ecotypes don’t mix, even though there’s nothing stopping them. They’re genetically compatible. Their territories overlap. They encounter each other in the open ocean all the time, but apparently they don’t like to intermingle due to what Scientific America calls “cultural differences.”

We should be careful about anthropomorphizing animal behaviors. When Scientific American says orcas have “cultural differences,” they mean they have different hunting and feeding practices. And also different clicking/whistling patterns for communication.

Actually, that does sound a little bit like orcas have human-like languages, and maybe even a primitive version of human-like culture. And those linguistic and cultural barriers are enough to keep them apart. We really should tell them about Shakespeare. They’d probably understand a lot of Shakespeare’s themes.

P.S.: You may have missed it, but I was trying to make a West Side Story reference with that thing about antelope.

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Sciency Words: Zoosemiotics

November 4, 2016

Sciency Words MATH

Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us expand our scientific vocabularies together. Today’s term is:

ZOOSEMIOTICS

Sometimes with these Sciency Words posts, I feel like I’ve bitten off more than I can chew. This is one of those times.

Semiotics is a field of study related to linguistics, but more focused on the creation of signs and symbols and how these signs and symbols can be used to communicate meaning. Zoosemiotics is the study of how animals do that.

Think of birdsong or whale-song, or the dance of bees, or ants laying down scent trails, or dogs marking their territory, or squid rapidly changing colors, or all the crazy displays animals put on to attract mates. Or think of the way pets very pointedly stare at you while you’re eating.

There are three basic types of communication that zoosemioticians study:

  • Intraspecies zoosemiotics: communication between animals of the same species.
  • Interspecies zoosemiotics: communication between animals of different species.
  • Anthropological zoosemiotics: communication between animals and humans.

In each case, we have an animal engaging in some sort of behavior that symbolically expresses meaning. On the other side of the equation, we have another animal (or animals) trying to interpret that behavior. If the behavior is interpreted correctly, we have communication!

And when animals communicate frequently, relationships can develop. A sort of culture might start to emerge. Animals may even form a kind of social order. Studying the culture and social orders of animal groups is also part of zoosemiotics’ domain, and this is where I think things get tricky.

It’s a little too easy to anthropomorphize animals, to assign human emotions and human motivations to their natural animal behavior. So just how human-like are animal communications? How human-like are animal “cultures” and “social orders,” according to zoosemiotics? Or should we rather ask how animal-like are humans?

This starts getting into a lot of heavy philosophical territory that I’m probably not qualified to talk about. I mean, I’m not a zoosemiotician. I only learned about this term a week ago, and I have a lot more research to do. For now, I’m just happy to have a new word to add to my scientific vocabulary.

P.S.: Xenosemiotics doesn’t seem to be a word yet, but it totally should be.


Sciency Words: Conan the Bacterium

October 7, 2016

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Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us all expand our scientific vocabularies together. Today’s term is:

CONAN THE BACTERIUM

Meet Deinococus radiodurans, a species of bacteria found in truly unexpected locations all over the globe. It’s said to be the toughest bacterium in the world. It’s so tough that it’s earned the nickname Conan the Bacterium.

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Don’t panic. Conan the Bacterium is nonpathogenic and does not represent a threat to humans.

Some microorganisms are referred to as extremophiles, because they’ve adapted to survive in some specific extreme environment. Conan is a polyextremophile, because it has adapted to survive in a wide variety of extreme environments. Among other things, Conan can endure:

  • Highly acidic environments
  • Airless environments
  • Waterless environments
  • Extremely cold environments
  • Extremely radioactive environments

Frankly, it sounds like this little bugger is perfectly adapted for life on Mars, but according to my reading, its genome suggests that it did in fact evolve here on Earth.

Conan’s resistance to radiation is of particular interest to science. It seems that whenever radiation damages Conan’s DNA, even if the DNA is shredded into tiny bits, Conan can stitch its DNA back together again in as little as twelve hours.

Lots of organisms, including humans, have some ability to repair their own damaged DNA. Conan is just a whole lot better at it than the rest of us, and no one’s sure why.

I first learned about Conan the Bacterium in a book called All These Worlds Are Yours: The Scientific Search for Alien Life. I’ll be doing a book review early next week.


Molecular Monday: Liquid Water vs. Liquid Methane

September 5, 2016

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Welcome to Molecular Monday! On the first Monday of the month, we take a closer look at the atoms and molecules that make up our physical universe. Today, we’re comparing some of the properties of:

LIQUID WATER AND LIQUID METHANE

So you’re a moon or other planetary body, and you want to get some biochemical action going on. First, you need some organic substances. Titan has set a great example with the tholin haze that forms spontaneously in its atmosphere.

Next, you need a liquid to dissolve that organic material in, in the hopes that the organic material will recombine as amino acids, peptide chains, and ultimately DNA. But which liquid should you choose? Liquid water (as seen on Earth) or liquid methane (as seen on Titan)?

Pick Water!

Water (H2O) makes an excellent solvent for our purposes because it’s a polar molecule. There are two big reasons for water’s polarity.

  • First, oxygen has an extremely high electronegativity, meaning oxygen atoms like to yank electrons away from other atoms. Within a water molecule, oxygen’s electron-hogging tendencies cause it to become negatively charged, while the two hydrogen atoms become positive.
  • Second, you know how water molecules have that Mickey Mouse shape? Because of that shape, with the two hydrogen atoms bent toward each other, the positive charges accumulate on one side of the molecule and the negative charge accumulates on the other.

Thus, water is a polar molecule, and it’ll go around interacting with other polar molecules, like tholins or amino acids.

Don’t Pick Methane

Unlike water, methane (CH4) is a nonpolar molecule. Why?

  • Carbon is slightly more electronegative than hydrogen, but not by much, so the atoms in a methane molecule share electrons almost equally. This minimizes the electric charges that might build up inside the molecule.
  • Methane molecules are symmetrical, with the carbon atom in the center and the four hydrogens evenly spaced around in, like the four corners of an equilateral pyramid.

Sp05 Methane vs Water

Any electrical charges in a methane molecule balance out, due to the molecule’s symmetry. And those charges are fairly weak anyway, due to the similar electronegativities of carbon and hydrogen.

I won’t be so bold as to say life can’t develop in a liquid methane environment, but the idea does seem a bit farfetched in light of the chemistry. Polar molecules like tholins just aren’t likely to dissolve in a methane lake, like the lakes found on Titan.

On the other hand, the universe keeps surprising us, and the giant lake monster I recently met on Titan might dispute my assessment of Titan’s biochemical potential.

P.S.: Titan’s lakes also contain liquid ethane, but that doesn’t really change anything. Ethane is also nonpolar.


Sciency Words: Endosymbiosis

June 17, 2016

Sciency Words MATH

Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us all expand our scientific vocabularies together. Today’s term is:

ENDOSYMBIOSIS

The story goes like this: long ago (roughly 1.5 to 2 billion years ago), two single-celled organisms reached a mutually beneficial arrangement.

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Or perhaps one single-celled organism imposed a mutually beneficial arrangement on another.

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Whichever way it happened, the result is what we now call endosymbiosis. It’s a term which comes from a bunch of Greek words meaning “living together” and “inside.”

The word endosymbiosis can be used to describe any mutually beneficial (non-parasitic) relationship where one organism lives inside another. Think of the bacteria living in your stomach helping you digest your food.

But typically, the term seems to be reserved for such relationships between single-celled organisms. One cell is called the host. The other—the one living inside the host—is called the endosymbiont.

Each individual cell in your body contains tiny internal structures called organelles. This is true not only for humans but all animals and plants, and many microorganisms, such as the amoeba or the paramecium. The presence of organelles is one defining characteristic for all eukaryotic life forms on Earth (as opposed to prokaryotic life forms like bacteria or archaea).

It is believed that, at some point in evolutionary history, all these organelles started out as endosymbionts. Some organelles, like mitochondria and chloroplasts, still have their own DNA separate from the DNA of the cell nucleus.

But at what point did the transition occur? At what point should we stop calling something an endosymbiont and start calling it an organelle? That question gets into some murky territory for biology. The distinction between organelles and endosymbionts is rather too poorly defined at the moment for a Sciency Words post.


Sciency Words: Equilibrioception

June 3, 2016

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Today’s post is part of a special series here on Planet Pailly called Sciency Words. Each week, we take a closer look at an interesting science or science-related term to help us all expand our scientific vocabularies together. Today’s term is:

EQUILIBRIOCEPTION

The best writing engages all the senses. That’s worthwhile advise most writers will get at some point in their careers, but how many senses do we humans have?

Thousands of years ago, Aristotle concluded that we have five senses: sight, hearing, taste, smell, and touch. That seems reasonable enough, and five continues to be the traditional number of senses. But depending on whom you ask, you might get a different answer.

Equilibrioception is a sense we rarely have to think about, unless something goes wrong with it. It’s governed by the vestibular system, which is located in your inner ear.

Basically, equilibrioception is your perception of up and down. It’s your ability to orient yourself in relation to gravity so that you can keep your balance while standing or walking.

If you’re writing science fiction—especially hard Sci-Fi—this is a sixth sense you may want to think about (telepathy just got bumped to seventh sense!). The experience of zero-G, or fractional Gs, or Gs greater than one, could really screw with your characters’ heads.

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Even experienced astronauts are known to have equilibrioception-related problems from time to time.

As for artificial gravity, it might “feel” a bit off too. If you’re simulating gravity by rotating your spaceship, as seen in movies like 2001: A Space Odyssey, you might experience a gravity-like pull that is skewed slightly relative to the floor. Or your feet might experience slightly more Gs than your head (especially on smaller spacecraft).

So science fiction writers, remember to engage all the senses in your writing, even senses like equilibrioception that we don’t normally think about. And if you manage to give your readers a bit of vertigo, you’ve done your job well.

Links

How to Pronounce Equilibrioception

Humans Have a Lot More than Five Senses from Today I Found Out

You Don’t Actually Have Five Senses from Modern Notion.