No one likes feeling stupid, least of all the “smart” people. And yet, the Universe is a massive, unfathomable place which makes us into idiots daily. Remember, it’s not about having all knowledge between your ears, but knowing where to find it as you need it. The Internet makes that bit real easy. Before starting my recent project, Final Solution, there was much I knew of space only from hearsay. Both my father and grandfather are avid space enthusiasts, and so they spoke of space a great deal as I grew up. However, only a portion of this was based on hard facts, and my memory as a kid was a kid’s memory. Go figure.
So when I started Final Solution I wanted to get it right, like any good writer would. I challenged what I already knew and explored a whole lot of what I didn’t, or had forgotten.
(As a side note: I made an inter-generational space craft model for my 6th grade science fare project explaining how a self contained ecosystem could keep humans alive for hundreds of years while traveling through deep space. I won some sort of prize, I think.)
Here’s just a few questions I’d either forgotten the answer to, or had never known for truth. Until now…
1. How do we know how far away the stars are?
Parallax—because Pythagoras was one bad mother f*cker. This one baked my noodle for years, because, well, it’s not like we can stretch out a measuring tape thousands, sometimes, millions of light years away and see what happens. It’s not like we can shoot a radio wave at them and see how long it takes to bounce back either. It’s way too far away. So how do they do it?
Triangles. Solve for X.
“The first technique uses triangulation (a.k.a. parallax). The Earth’s orbit around the sunhas a diameter of about 186 million miles (300 million kilometers). By looking at a star one day and then looking at it again 6 months later, an astronomer can see a difference in the viewing angle for the star. With a little trigonometry, the different angles yield a distance. This technique works for stars within about 400 light years of earth.” Source: http://science.howstuffworks.com/question224.htm
But how do we account for the ones that are REALLY REALLY far away, like millions of light years?
“To measure the distance to a galaxy, we try to find stars in that galaxy whose absolute light output we can measure. We can then determine how far away the galaxy is by observing the brightness of the stars. Such stars can help us measure the distance to galaxies 300 million light years away.” – Source: http://hubblesite.org/reference_desk/faq/answer.php.id=45&cat=galaxies
When it’s laid out like that I feel as if…
2.How did we know space was a vacuum before exploration?
This was a question I’d had for years, but until the invention of the internet wasn’t exactly sure what book in the library to check. I was too busy with girls to dig at the time.
Here’s 2 ways:
“Pascal (1640’s) also predicted that this pressure would diminish at higher altitudes. He asked his bother in law Florin Perier, who lived near a mountain, to test the idea. Receiving proof, Pascal suggested that air would thin out into a vacuum at still greater altitudes…for centuries, it was believed that air had no weight. But in fact it exerts a measurable force per surface area of the earth. Blaise Pascal demonstrated atmospheric pressure by inverting a mercury filled glass tube over a mercury reservoir. The tube’s mercury falls to create an airless space (a vacuum), but atmospheric pressure pushes down on the reservoir to maintain a column: the bigger the pressure, the taller the column.” – DK “Science Year by Year”
“We can tell that most of the Universe is a vacuum because matter absorbs and scatters light. We can accurately measure the amount of material between us and stars, and that gives an average density of gas in the Galaxy of only one atom per cubic centimeter. That’s a better vacuum than we can achieve in a laboratory.” Source: http://helios.gsfc.nasa.gov/qa_sp_ms.html
Like all good science, we observed the little things and used that to get an idea of the bigger things. We observed light being reflected, and detected small changes in pressure atop mountains. Extrapolate that into the unknown and it seemed very likely the sky was a massive vacuum.
3.What really happens when your exposed to the vacuum of space?
Your head explodes instantly. Nahh, just kidding. Or am I?
There’s no air in space, that much is a given, but more importantly, there’s no atmospheric pressure. So, if you don’t exhale when entering a vacuum, the gas in your body will expand and make you explode. While this might not actually happen, it is possible. Without the atmospheric pressure the gases in your body will try and equalized to fill the space around you. That’s just what gas does.
Now, assuming you exhale, as the oxygen dissipates from your body within a few seconds, you will lose consciousness and air embolisms will appear in your blood (like divers). Your tissues will swell but not explode due to their elasticity, and even if you’re put back into a pressurized environment quickly, you will have one serious case of decompression sickness (the bends).
So basically, humans weren’t meant to be in space. Then again, we weren’t meant to climb Mt. Everest, or fly, but we do it all the time. It’s a calculated risk we take, and not so lightly.
4.How cold is space?
Technically, space has no temperature. That said, it’s around 3 degrees above absolute zero (in Kelvin). Confusing? Just a little. It’s all about perspective.
It comes down to 3 simple concepts. Temperature (heat) is essentially the movement or excitation of particles. It can only be transferred by conduction (touching), convection (through the air), and radiation (like the sun). Heat only travels through space by radiation, or photons being absorbed by an object (the more it absorbs the hotter it gets, the more it loses the colder it gets). This is why, say, the International Space Station will reach blistering temperatures on the sunny side, and frighteningly cold ones on the dark side. Barring air to conduct this transfer of heat, or a giant rod from the Sun being attached directly to the ISS, that leaves only radiation. And that radiation only reaches one side.
The vacuum of space is not cold, per say, it just has no substantial heat.
So, then why is space 3 degrees above absolute freezing, or the temperature at which all matter ceases to move? Simple, background radiation the result of “The Big Bang”. If an object is left in deep space for long enough, and is far enough away from the Sun or any other star, it’s heat will eventually equalize with that of the Universe’s background radiation and voila, we have just enough heat to keep matter from ceasing to move.
But 3 degrees above absolute zero isn’t anything to get excited about, I know the particles aren’t very excited at all.
See what I did there? *nudges you with an elbow* Ey?
5.Is a “Nuclear Battery” really a battery?
The short answer: Nope.
If you’ve recently watched The Martian or read its book by Andy Weir, you’ll remember the RTG or “Radioisotope thermometric generator”. That’s what is commonly called a nuclear battery, but its a bit of slang. Simple explanation, “The terms atomic battery, nuclear battery, tritium battery and radioisotope generator are used to describe a device which uses energy from the decay of a radioactive isotope to generate electricity. Like nuclear reactors they generate electricity from atomic energy, but differ in that they do not use a chain reaction.”
So basically, some pebbles of radioactive material decay, producing heat, which in turn runs a generator. Since Voyager, all of our deep space probes have contained one sort of RTG or another, most recently the Cassini Space Craft which actually has 3 RTGs, being that solar power is vastly less useful the further away from the Sun you travel. That said, NASA is testing the limits of our solar power’s reach with the Juno Spacecraft, a Jupiter probe which currently holds the record at 792 million kilometers from the Sun and still operating on solar.
But, the real question you want to ask, is could an RTG really keep Mark Whatney warm in his rover. Answer? Yes. Yes it could. There’s a reason they buried that bitch in the ground.
6. And the kicker, what’s a “period” like in space?
Yup, that’s right, and it’s been a topic of discussion for YEARS. I’m gonna thank NPR for answering this one, and not do so much editorializing (being that I was born with an XY chromosome). Apparently, though, this was a big concern in having women astronauts (though part of me wants to believe that it was just a male dominated society being dicks as well).
“They feared that microgravity might increase the incidence of “retrograde menstruation.” Blood might flow up the fallopian tubes into the abdomen, causing pain and other health problems. No one actually did any experiments to see if this really would be a problem, so there weren’t any data to support or refute these fears.”
Seriously? I mean, I guess we didn’t know but damn.
We all know lady folk have been in space (and they totally rock the killer micrograv hair), so verdict?
“…what does happen when you get your period in space? The same thing that happens on Earth! In the past three decades of female space flight, periods in space have been normal — no menstrual problems in microgravity.”
Rest assured my female kin. You will suffer just as bad as on Earth (I guess that’s the price you pay for being the Mothers of humanity).