Monday, July 11, 2011

Space, Outer and Inner (Part I)

Since May of last year, after the abyssal horror of the Final Fantasy XIII experience forced me to reevaluate how I spend my time, I've been stargazing and reading up on astronomy as an alternative hobby. Among the most remarkable observations I've made is how little the topics of astronomy and outer space seem to interest people.

Last February I showed a few acquaintances the Orion Nebula through my fancy binoculars. (Around that time I was habitually taking a peek at it nearly every evening. Not that it changes or does anything perceptibly different on a night-to-night basis, but the sight of it is astonishing -- all the more so, I felt, because I could see it with my own eyes.) When I mounted the binoculars on a tripod and invited these folks to see it for themselves, they each look for a few seconds and went back inside. Their reactions ranged from underwhelmed to disappointed.

(Here we find an unfortunate side-effect of the Hubble Space Telescope. People unaccustomed to looking through telescopes become familiar with fantastic images like the Pillars of Creation and the Hubble Deep Field, thereby setting expectations that a regular telescope simply can't match. By the time you finish explaining to them that it's unrealistic to expect a portable optical device to match the quality of images produced by a multimillion-dollar roboscope looking out from above the atmosphere through a lens with a 0.05 arc-second resolving power and enhanced by computer processing, your guests have already gone in to watch Nyan Cat for another half hour.)

I don't expect that everyone should be as fascinated by the heavens as I am, but I would think that they should hold at least some interest to most people. Instead, I've found that the subject usually arouses mild indifference or antipathy. During a car ride when I had a Richard Feynman lecture on gravitation in the CD player, my friend in the passenger seat asked, with some exasperation, why I chose to concern myself with something that made no practical difference in my life.

"You're going to stay home and look at the stars? What, you wouldn't rather come out to a bar? Why don't you go out and meet people? You should be trying to meet girls. You need a girlfriend, Pat. If you had a girlfriend, why, you wouldn't be so lonely that you'd choose to stay at home by yourself and look at the stars instead of coming out to the bar."

That which is most immediately useful about studying space (in any degree of intensity) is also what makes it such a tantalizing subject. It lends a certain perspective to your view of the world that is difficult to attain elsewhere in your day-to-day life. (I use "world" in the subjective sense, as opposed to the objective "Earth.")

Here's something you might do for yourself to see what I mean. Go outside tonight around 11:00 or so. (Actually, it might help to wait a week or two so that the moon isn't so damned bright) and find the Big Dipper. (Hint: look north.) If you follow the stars of its "tail" and keep moving in the same curved line, you'll bump into a bright star. Trust me, you'll know it when you see it.
This image, courtesy of Astrobob, will give you some idea of what to look for.

Do note that it won't be as far west as the picture (taken in mid-September) indicates.

This star is Arcturus, the second-brightest star in the night sky of the northern hemisphere, and the centerpiece of the constellation Boötes, the plowman. (Regrettably, the name isn't properly pronounced as "boots;" try "boh-OH-is," instead. However, I will forgive you for saying "boots," as I am guilty of doing it even though I know better.)

Anyway. Once you find Arcturus, begin moving your gaze eastward. The next bright star you find will be Vega (like the Street Fighter character), of the constellation Lyra. If you move your gaze to the southeast, you'll see a second bright star: Altair (like the Final Fantasy village) of the constellation Aquilla. Returning to Vega and looking toward the northeast, you will find a third bright star forming the "head" of a cross-shape formed by three dimmer stars. This bright star is Deneb, of the constellation Cygnus. (As far as I know, no video games reference Deneb.)

Vega, Deneb, and Altair form the corners of the Summer Triangle. Again, from Astrobob:


You should be able to see these three stars even if you live in an urban area with a lot of light pollution. This next step, however, requires you to look from a suburban or rural area, and be carrying a telescope or pair of binoculars.

As you probably know, our galaxy's shape is that of a flat disc. "Flatness," especially in this case, is a matter of proportion. Compared to its 575,205,347,300,000,000-mile (or so) diameter, the Milky Way's 76,694,046,300,000,000-mile (or so) thickness is quite flat.

Since we're looking out at the disc from an object inside the disc (and located toward its outer rim), we perceive the bulk of it a wide band arching across the firmament. In the absence of light pollution, it is dimly visible to the naked eye as a pale streak stretching from one horizon to the next. Not understanding the nature of what they were looking at, the ancients named it the Milky Way and invented a myth to explain it. When we came to realize that the arc represented the largest visible portion of our parent galaxy, we came to identify that galaxy by the name given to the visible arc.

(I apologize if I am repeating something you already know. But from what I recall from my thirteen years in the United States' public school system, I don't believe the curriculum ever addressed anything beyond Pluto in much detail. I can't be certain what anyone else reading this knows or doesn't know.)

The Summer Triangle is superimposed over the Milky Way band. If you're looking from a sufficiently dark region, you don't need me to point this out to you. It can be visible from the suburbs, but you'll need an optical aid. (More powerful is always better, but you can still get a decent glimpse using a pair binoculars designed for, say, watching a football game from the nosebleed section.)
All you have to do is point your scope or your nocks into the center of the triangle and look. If you've never tried it, you might find yourself shocked at how much stuff is out there -- how much light from how many stars are hitting your optic nerves all at once. In a place with moderate light pollution, you might see hundreds. In a place with little or no light pollution, you may see thousands.

If you attended public school in the United States (as I did), you probably received a crash course in astronomy. Chances are that curriculum botched it, as my school's did. The lesson probably went something like this:

"The Moon orbits the Earth. The Earth orbits the Sun. The Sun is very large and made of incandescent gas. The other stars are like the sun, but they are very far away. Are you writing this down? The true/false quiz is on Thursday."

We make a grave mistake by teaching students the facts without informing them as to how we arrived at them. This is like making them memorize the solutions to math problems without teaching them how the problems are solved.

Teaching the facts of science without teaching the methods is only marginally better than pointless.

The purpose of science is to arrive at a more accurate understanding of the physical world though repeated observation, testing, and logical reasoning, with methods that are available for anyone (with the proper know-how and materials) to duplicate themselves. When the answers are given without reference to the process, the student cannot properly appreciate them. For all he knows, the facts in his textbook came from some Neo-Delphic Oracle sealed in a wine casket in some Princeton basement.

On a political note: if science wants to assert itself as the superior alternative to religious dogma where finding out the physical facts is concerned, scientific education must make a better effort toward demonstrating to students that it can do one crucial thing that dogma cannot -- it can show its work.

For instance:

We know that the moon orbits the Earth because of how is path across the celestial sphere differs from those of the sun, the planets, and the stars. We know the Earth orbits the sun for the same reason, and by the same logic we find that the other planets orbit the sun as well. (Mr. Copernicus outlines it very succinctly and eloquently, even though he does fudge a few relatively minor details.)

We deduce that the sun is very large because, for starters, we can use radar to acquire a precise measurement of Venus's distance from Earth in kilometers, and then use that number in conjunction with Kepler's Third Law (p^2 = a^3) to find the a value of a (in this case, 1 A.U., or one "Earth-distance") in kilometers. Knowing exactly how far away Venus is from Earth, and knowing exactly how far away the Sun is from Earth, we observe that the sun appears thirty times larger than Venus in the sky, despite being 2.6 times farther away. The conclusion draws itself.

We understand that the stars are very far away because of observations involving stellar parallax. (Hold your raised index finger six inches from your eyes. Close your left eye. Now open it and close your right eye. Notice how drastically the apparent position of your finger seems to change in relation to object behind it. This is parallax. When we view objects like the Moon or planets from different positions on the Earth's surface,and compare where they appear to lie relative to the stars, we observe a similar displacement.

We know that the stars are similar to the sun in composition because spectroscopic analysis turns up evidence of the same basic materials in the sun and in pretty much every other star we can find.

(I should mention that I am by no means whatsoever an expert or authority. I am only an amateur who wants to share what he has learned.)

Before you take a good look, it helps to know what you're seeing, especially in this case. An object like a star is impossible to touch, approach, turn over, smell, etc. When we tell a student that the star he sees is one particular thing as opposed to numberless other particular things, it is no less important that he gets some understanding of how we came to this conclusion. Otherwise, he has as much a basis for believing that the twinkling dots he sees in the night sky are tremendous fusion-fueled orbs billions of miles away as he does for believing that the weatherman is telling the truth when he smiles, winks, and pulls up the Santa Radar on Christmas Eve. (Do weathermen still do this?)

So what are we seeing when we aim our scope into the middle of the Summer Triangle? The short answer is "stars." Thousands upon thousands of the billions upon billions of stars composing the Milky Way galaxy. Most of these stars are at least similar in size to our Sun, whose diameter is somewhere in the vicinity of 64,950 miles. (Our entire world's diameter amounts to 7,926 miles, remember.) Though they appear close together, the distances between each of these points of light you see are so tremendous that to reckon them in miles would make about as much sense as measuring the length between city blocks in millimeters.

What you're looking at is Eternity. But only a sliver of it.

Thanks to advancements in optics, we now understand that the Milky Way is just one galaxy out of billions and billions.

Here's a fun experiment! This BBC article might be outdated and/or inaccurate, but that's okay. It gives us a number to play around with: 156 billion. Let's say that the universe is 156-billion light-years wide. If we're assuming it's a sphere (the truth is probably a lot more complicated and far beyond my ability to approach), that gives it a radius of 78 billion light years -- or 458,200,000,000,000,000,000,000 miles. Now if we calculate the volume of a sphere with a radius of 458,200,000,000,000,000,000,000, we get...

(4/3) * (π) * (458,200,000,000,000,000,000,000)^3 = oh jeez.

Uh...I'm getting 40,295,250,862,323,019,768,114,206,530,184,000,000,000,000,000,000,000,000,000,000,000,000,000 cubic miles. This is a very sloppy, simplistic, and definitely incorrect approach (it doesn't account for any relativistic space-stretching voodoo, for one thing), but it gives us some idea of how far existence might go. (Earth's volume is about 259,875,899,200 cubic miles. Subtract that from the "number" up above and contemplate how much stuff that's not us is.)

It is very easy not to think about this in your daily life. Most of us probably don't give it a second thought. Stargazing is a pursuit that rather forces you to confront this reality -- though usually in small doses. (When faced with a number as large as the one above, the size of the Milky Way is no less piddlingly infinitesimal than that of the Earth.)

I don't know of anyone who has not been taught that the Earth revolves around a massive Sun and that the universe outside our neighborhood is bigger than we can possibly imagine. Most of us are even used to the idea, but the fact is so rarely brought to bear on our day-to-day existence that we rarely appreciate the significance of this fact.

You can look at Hubble images and listen to Carl Sagan wax poetic about the cosmos, but neither brings you into direct contact with the subject. This is why you need to sometimes go out and be touched by it -- to see, with your own eyes, a thousand stars stretched out over billions of miles.

When formulating an opinion or viewpoint on any subject, it is important to consider as much of the whole of the situation as possible. Otherwise you risk an incomplete conclusion.

When we evaluate ourselves, our world, and ourselves in the context of our world, we cannot omit the underlying facts of the situation. Though we rarely have any direct contact with it, Eternity is there. When assessing himself and his environment, the average person fails to factor it into his personal equation.

Why should he, though? Why fuss over something that brings no immediate (or even perceptible) weight upon his health, his friends, his career, and his hobbies?

This has already careened far enough along for now, but for now I'll close with a question. Even if a person has not given it any direct thought, he is very likely to have already arrived at his answer without being asked.

"Which is more real: the part(s) of reality existing closest to me, or the parts of reality occupying the greatest percentage of the whole?" 

[cont.]

Edit: Says a commentator on Twitter:

they're both equally real this question is dum

I was afraid of this. Maybe that's not the question I want to ask. Maybe what I'm turning over in my addled brain is a matter of significance.

Are the constituents of reality which exist in closest proximity to my experience more significant than the overwhelmingly larger span of reality (matter, energy, time, space, et al) existing outside of my environs?

Why or why not?

And why should this question strike most as an "empty academic point?"

5 comments:

  1. In relativity, everything is measured based on our perspective or what is relative. Since everyone's perspective is different, the constituents of reality that are closest to us would have the most effect on each individual perceives and, therefore, their experience. Since we give great importance to the differences between our experiences, rather than the fact that we all experience cosmological constants, (in your example, the larger span of reality) the differences are more important.

    Why should this question strike most as an "empty academic point?"
    Short answer: People are sheep.

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  2. As you've probably deduced, astronomy does not hold the attention span of most because it is quite literally out of our reach. As soon as you ponder enough to realize just how vast the universe actually is it becomes distant and seemingly unimportant. You can try and explain to people why understanding the stars is in fact relevant, but many have a hard time wrapping their heads around that. Most of us will never go higher into space than what your standard airplane can achieve and most of us will never know exactly what it is we're looking at. Space is "out there"; life is "down here". The fact that they are really one and the same seems to get missed quite often.

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  3. It is far easier to believe in God than to fathom the significance of a quasar, or cosmic strings. Even in first world countries, where we owe it to the continued survival and dominance of our species to fully consider, appreciate, and be awed at the complexity, chance, beauty, and depth crystallized within the life of one homo sapien - rather than live for the promise of something better, after, like our more ignorant ancestors. Summed up, stop searching for Jesus and start looking for quasars.

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  4. The other Adam says: "As soon as you ponder enough to realize just how vast the universe actually is it becomes distant and seemingly unimportant."

    It's weird, this tends to give me the opposite feeling, that my little corner of the universe is unimportant. Makes me want to drop whatever I'm doing and study astronomy, but then I go to sleep and forget it on waking. I get those "dedicate life to studying X" moods more and more lately.

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  5. Metal Machine Mage: Makes sense to me!

    Adam #1: Also true, but it rather seems like intellectual laziness on behalf of the greater section of the populace. At least it does to me, anyhow.

    Phanto: Here, here. That's an excellent starting point. It is my humble opinion people shouldn't live expecting something better after life, but should work to make life better for everyone else. To this end, expanding the general populace's understanding of the physical world and humanity's place in it (how we affect it and how it affects us) is crucial.

    Adam #2: Maybe your soul is trying to tell you something!

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