THE SOUTHWORTH PLANETARIUMAs for the name "change," this new e-mail system is using my first name, James, instead of my middle name, Edward, which I have used as my primary name since I was 15. (My wonderful mother still thinks its a phase I'm going through.)
207-780-4249 www.usm.maine.edu/planet
70 Falmouth Street Portland, Maine 04103
"Gee....we wonder what the number one movie this weekend will be?"
THE DAILY ASTRONOMER
Wednesday, December 16, 2015
Star Wars Astronomy
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Two personal notes:
Happy Birthday, Brother Richard!
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We just cannot resist any type of hype. This week, the planet's seven billion plus inhabitants are all camping out in front of theaters anxiously awaiting the opening night for Star Wars VII "The Force Awakens." From the children desperately engaged in light saber battles to the dyspeptic uncle who, having seen Darth Vader's face on a espresso flavored Coffee Mate container, now thinks the world could only be improved with a proximate supernova, Star Wars pervades the planet and nobody can escape from it. The current mania is somewhat reminiscent of the hysteria that attended the 1977 movie "A New Hope." Therefore, we want to join in the "fun," with a DA article pertaining to both the science and the fiction behind the Star Wars Universe. After all, Star Wars hasn't received nearly enough attention lately.
A LONG TIME AGO IN A GALAXY FAR, FAR AWAY
This famous opening line prompts the question: could alien life have existed a long, long time ago? We know that advanced life forms cannot exist without an abundance of complex molecules that, themselves, are composed of "heavy elements," such as oxygen, phosphorous, carbon, and others.* Only the simplest elements, primarily hydrogen and helium, existed during the Universe's infancy. The first generation of stars manufactured the "metals," defined astronomically as the elements heavier than helium. These stars, being the highly massive population III, would have exploded as supernovae, thereby enriching the galaxy with an infusion of all the heavy elements. This chemically rich material would have then become incorporated into other star/planet systems. On these heavy element laden planets the first life might have developed. The life might have evolved from the simplest prokaryotic cells to a galaxy-dominating empire. We assume, based on Earth's evolutionary time frame, that such a process would have required at least five to six billion years. As humans haven't yet become a star faring race, we haven't the faintest idea how long such a progression would require. After all, humans haven't yet ventured more than a quarter of a million miles from Earth. We're a long way from zipping between star systems.
The upshot of it all is that the Universe might well have produced mighty empires in distant galaxies that have long since vanished. We can't know if they existed, of course, but we can at least be confident that the necessary chemical building blocks have existed in the cosmos for billions of years.
The assumption we've made is that we're actually now observing the "Star Wars" galaxy as it was when all that transpired on film was happening. If it all occurred a billion years ago, the galaxy is a billion light years away from us. Then, again, there is a slight possibility that we're over thinking it.
LASER GUNS
As impressive as these weapons appear, we certainly hope they weren't expensive, because they truly don't work well. Let's assume you are surrounded by a doom of storm troopers,** but, fortunately, you're armed with a laser gun. You fire indiscriminately at your assailants, some of whom deftly dodge the rays, while others are slain by them. Then, of course, you realize: these accursed beams are moving very slowly! A beam of light travels at more than 186,000 miles a second in a vacuum and at nearly the same speed in air. If the storm trooper can avoid the beam, it is traveling thousands of times slower than lasers actually travel. It is true that a laser pulse can fry a nervous system and make short work of storm troopers, even though they are completely enclosed in the most expensive armor the Empire can buy. However, someone should tell the Empire engineers to remove the anchors from the beams because the light is moving like its 145 years old and doesn't really care any more.
WARP SPEED
Remember that scene when Han Solo was piloting the Millennium Falcon and then floored it to light speed? Well, how could one forget! The pinpoint stars rapidly elongated to luminous lines converging to the middle distance. If I might include a brief personal recollection. I remember my brother, Richard, took me to see the 1977 Star Wars movie and just before Han et al accelerated to warp speed, he nudged me and said, "Watch this!" I did and was, of course, astonished and said, to the delight of nearby viewers, "Wow, Dic, tell him to do that again!" Now, had I known then what I pretend to know now, I would have instead said, while pedantically waggling an index finger, "Now, Richard, you realize that if those oddly dressed people were actually traveling on board a vessel traveling at light speed, they wouldn't be able to converse because time stops at light speed. The Theory of Special Relativity tells us that time dilates on any moving object and that dilation relates directly to the speed. The faster the vessel, the greater the dilation. If the Millennium Falcon had achieved light speed, time would stop. Of course, the ship's mass also increases with increased speed, so its mass would essentially become infinite at light speed, which would preclude it from attaining that velocity."
And, we agree....the "Wow, Dic, tell him to do that again!" was the far less annoying thing to say.
RULING THE GALAXY
Alexander the Great would have liked this: he would never have run of out worlds to conquer. In the Star Wars Universe, the Empire ruled an entire galaxy with a particularly hard iron fist. Such domination would have necessitated the development of a particularly advanced hyperspace travel and communication infrastructure. Let's imagine that someone wants to govern the Milky Way Galaxy. According to recent estimates, our one galaxy contains more than 200 billion stars and, perhaps, an equal or even greater number of planets. Quite a lot of real estate to have under one's dominion. One would require untold trillions of minions to do one's bidding and one would also need the means by which to convey the latest dictates instantaneously to all your myriad underlings. If you were constrained by light speed, you wouldn't be able to maintain order. Let's just say a planet full of troublesome upstarts on the other side of the galaxy starts to go all Libertarian on you and resists the Empire. You decide to send them a placating message of "Shut up and deal with it!" Even if the message travels at light speed, it would require tens of thousands of years to reach them, by which time the original agitators will have long since perished. So, too, would you.
Of course, there is always the Von Neumann machine method. An advanced alien race constructs a vessel capable of traversing great distances and self replication. As it travels through the galaxy, it visits various planets and mines raw materials from which it manufacturers components to construct a copy of itself. Once completed, this copy proceeds to also make copies of itself. These, in turn, would be self replicating so that after a comparatively brief time, perhaps 200 million years, Von Neumann drones could be swarming through the galaxy. Let's be cheerful and further assume they've also been programmed to conquer inferior races (i.e. all of us) and, being incapable of empathy, have no compunction about slaying the disobedient. Perhaps through the agency of these surrogates, a race could conceivably become both prevalent and domineering. Good luck collecting the taxes, though!
Then again, maybe the Star Wars franchise is just brilliant science fiction designed to delight audiences, inflame imaginations, and enrich the movie studios. That is just fine by us because there is nothing more electric and elating than escapist escapades into the remotest hollows of outer space.
*The vast majority of life forms consist primarily of six elements: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur. As we lack any knowledge of extra terrestrial life forms, we cannot know if these elements will be as predominant in alien beings.
**Yes, there are collective nouns specific to storm troopers and yes, I actually took the time to look it up and yes, somebody else took the time to make one up and then post it on line and yes, if you were a socially awkward geek type you'd also have plenty of spare time at night to learn collective noun words such as a doom of storm troopers, a shortage of dwarves, a debauchery of hedonists, a metamorphosis of ovoids, a wiggle of Elvis impersonators (you can't unsee that), a tabula rasa of empiricists and, G-d help us, a handful of palm readers.