esiegel | June 17, 2010"We are all captives of the pictures in our head -- our belief that the world we have experienced is the world that really exists." -Walter Lippmann
For a long time, humans have wondered about life on other worlds, and about worlds around other stars. Until the 1990s, this was mostly speculation and hope. But shortly thereafter, some clues started rolling in. In 1992, the first planet outside of our Solar System was detected, and three years later, the first planet around a solar-like star was found.
Only, something was awfully weird about this planet. You see, in our Solar System, Mercury…
esiegel | June 16, 2010"If anyone, then, asks me the meaning of our flag, I say to him -- it means just what Concord and Lexington meant; what Bunker Hill meant; which was, in short, the rising up of a valiant young people against an old tyranny to establish the most momentous doctrine that the world had ever known -- the right of men to their own selves and to their liberties." -Henry Ward Beecher
Yes, folks, on Monday it was Flag Day here in the United States. Like many flags, there's no shortage of stars on this one.
But these stars are merely symbolic, and not actually representative of stars in the night sky…
esiegel | June 13, 2010"All that I desire to point out is the general principle that life imitates art far more than art imitates life." -Oscar Wilde
It isn't only the wonders of the Universe themselves that impress me. Oftentimes, just as spectacular are the technological achievements that have brought those wonders to us. (Or, in the case of space exploration, brought us to them!) So for you today, I've got a fabulous song to go with this article: Weary Memory by Iron & Wine.
Weary MemoryAustralian artist Peter Hennessey has taken his appreciation to the next level. He's taken on many of the most famous…
esiegel | June 12, 2010"If we lived on a planet where nothing ever changed, there would be little to do. There would be nothing to figure out. There would be no impetus for science. And if we lived in an unpredictable world, where things changed in random or very complex ways, we would not be able to figure things out. But we live in an in-between universe, where things change, but according to patterns, rules, or as we call them, laws of nature. If I throw a stick up in the air, it always falls down. If the sun sets in the west, it always rises again the next morning in the east. And so it becomes possible to…
esiegel | June 10, 2010"A good heart is the Sun and the Moon; or, rather, the Sun and not the Moon, for it shines bright and never changes." -William Shakespeare
Did I ever tell you how lucky you are?
Lucky, indeed, to have the Sun for a star?
Our Sun -- the ultimate source of all the light, heat, energy, and life on our world -- is remarkable in how constant it is. In fact, we didn't even know just how constant it was until we launched the SOHO satellite, shown below.
SOHO has just released their results from more than 12 years of observing the Sun from space, and found that the size of the Sun has been constant…
esiegel | June 7, 2010"We can continue to try and clean up the gutters all over the world and spend all of our resources looking at just the dirty spots and trying to make them clean. Or we can lift our eyes up and look into the skies and move forward in an evolutionary way." -Buzz Aldrin
Sometimes, you go away for one weekend and you miss out on some awfully big news. So while I was competing in the USA Beard & Mustache championships (and I -- along with everyone else -- was put to shame by Willi Chevalier), some amazing news came back from our closest astronomical neighbor.
Back when the space race was in…
esiegel | June 3, 2010"Absence is to love what wind is to fire; it extinguishes the small, it enkindles the great." -Comte DeBussy-Rabutin
As many of you know, I'm not around for the rest of the week/weekend, as I'm off competing in the USA Beard & Mustache Championships!
But I wouldn't feel right without leaving you something to tide you through to next week, so here goes.
Image credit: ©2012-2013 ~Hitman35mm, via DeviantArt.
As unbelievable as it may sound, 100 years ago, this is what we thought the entire Universe was. Our collection of stars, known as the Milky Way, operating under Newton's Laws of…
esiegel | June 3, 2010"It isn't necessary to imagine the world ending in fire or ice -- there are two other possibilities: one is paperwork, and the other is nostalgia." -Frank Zappa
There are many websites around telling you that the world is going to end on the winter solstice -- December 21st -- in the year 2012. And one of the ways that people are saying the world is going to end is that, on this date, the Earth will pass through the plane of the Milky Way galaxy, destroying us all.
Where to begin with this? First off, let me show you what our galaxy looks like. When you look up at an extremely dark night sky…
esiegel | June 2, 2010"Vision is not enough, it must be combined with venture. It is not enough to stare up the steps, we must step up the stairs." -Vaclav Havel
It's arguable that vision is the most important tool that an astronomer can have. This was particularly important back before the invention of the telescope, as the greatest astronomers of their time (like Tycho Brahe) were renowned for their visual acuity.
How do you stack up? You were curious about learning how good your hearing was, but what about your vision? Well, you can always get your vision tested using a Snellen eye chart, and read the bottom-…
esiegel | May 30, 2010"Shave off your beard and wear a dress. You would be a great female impersonator." -Simon Cowell
No, this post has nothing to do with Simon Cowell, but like American Idol, I do have a song for you. Have a listen to Almost Cut My Hair by Crosby, Stills & Nash, while you enjoy the read. (And while Graham Nash has gone short, 40 years later Crosby and Stills haven't!)
Almost Cut My Hair.mp3Many of you were around last year, when I shaved my head (and then some) for charity. I went from having long, curly hair to having my head completely shaved. It was a brand new look for me, and although…
esiegel | May 28, 2010"You must live in the present, launch yourself on every wave, find your eternity in each moment. Fools stand on their island opportunities and look toward another land. There is no other land, there is no other life but this." -Henry David Thoreau
Maybe for you, Henry. But a century and a half later, we are explorers of many other lands, including this one.
Back in 2004, two rovers landed on Mars, Spirit and Opportunity. And while Spirit has gotten all the press with its trials and tribulations, Opportunity has quietly been, well, exceeding all reasonable expectations.
Opportunity landed in…
esiegel | May 27, 2010"Mortal as I am, I know that I am born for a day. But when I follow at my pleasure the serried multitude of the stars in their circular course, my feet no longer touch the Earth." -Ptolemy
When you look up at the stars in the night sky, perhaps the most striking thing that they do is rotate about either the North or South Pole, depending on which hemisphere you live in.
But what do you get if you look up at the same time each evening, night after night?
Well, unlike the planets Mars (in red) and Uranus (faint, to the upper right of Mars), the stars stay in the same exact spot from night to…
esiegel | May 24, 2010"Magic mirror on the wall, who's the fairest one of all?" -the Wicked Queen
For a galaxy, though, it's really not fair to ask which one's the fairest. It's simply too subjective of a question. But size, now that's something we can measure.
So, I ask you -- galaxies of the Universe -- to step forward and show yourselves! Galaxy, galaxy on the wall, who's the largest one of all?
Nice try, Andromeda. Our biggest sister, Andromeda, has about 400 billion stars that make her up. That's about 50% more than our Milky Way has, and it makes Andromeda the largest galaxy in our local group. Andromeda is…
esiegel | May 23, 2010"When a resolute young fellow steps up to the great bully, the world, and takes him boldly by the beard, he is often surprised to find it comes off in his hand, and that it was only tied on to scare away the timid adventurers." -Ralph Waldo Emerson
We definitely need a good song for this weekend, and the one I want to share with you is P.G. by Harvey Andrews. It turns out that this is an incredibly difficult song to find, but I heard it on internet radio (which I love, by the way) and did my best to record it and repost it here. (So that's why the sound quality is so poor.) But it's a…
esiegel | May 22, 2010"The moon's an arrant thief,
And her pale fire she snatches from the sun." -William Shakespeare
Let's assume you lived before we walked on the Moon. Before we had ever been to space, hell, even before the invention of the telescope. Why not go all the way back to before we knew the planets went around the Sun! You know, back when all you had to go on for knowledge of the sky was your eye.
Some nights, you look up at the sky, and what would you see? Instead of thousands and thousands of stars, something might be filling your sky with light pollution. Indeed, the closest astronomical body to…
esiegel | May 19, 2010"I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet. The function of man is to live, not to exist. I shall not waste my days trying to prolong them. I shall use my time." -Jack London
Most of you have seen a shooting star before, also known as a meteor.
They happen most frequently during (surprise) meteor showers, but occasionally (and sparsely) during other times of the year. Whenever a small bit of astronomical dust from outer space runs into the atmosphere -- even though it may be no bigger than a grain of sand -- it burns up in the…
esiegel | May 17, 2010"From the intrinsic evidence of his creation, the Great Architect of the Universe now begins to appear as a pure mathematician." -Sir James Jeans
Last time we met, I posed a mystery to you: why are globular clusters the smallest in the Universe?
And what's more than that, we never find them in isolation! We always find them bound to galaxies (or, if not bound to a galaxy, then within a cluster of galaxies; thanks Steinn), but never just off in deep space, floating on their own like some lone Death Star.
Like all structures in the Universe, everything we're talking about here -- stars,…
esiegel | May 16, 2010
You see that there is no war within you. You're on your own side, and you are your own strength. -Terri Guillemets
Many of you don't know this, but over the last couple of months, my wife and I have been taking night classes in partner acrobatics! Why? Just because it sounded like a fun, athletic and adventurous thing to do.
(And to make up the fun to you of not having a song last week, here's an amazing two-for-one, with The David Grisman Quintet's Flatbush Waltz / Opus 57, from a live performance during the summer of 2001.)
Flatbush Waltz / Opus 57
Although I don't think we'll ever…
esiegel | May 14, 2010"I may be an old lion, but if someone puts his hand in my mouth, I can still bite it off." -Wilhelm Steinitz
When you look at a typical galaxy, you usually find a disk, a bulge, and a few dots diffusely strewn about the exterior.
Like an old lion, these dots have been around for a very long time: often for longer than the galactic disk itself! Just what are these things? Well, we can learn a little more if we look in the X-ray (with Chandra) and the infrared (with Spitzer), in addition to a visible light image (from Hubble). Let's take a look at a composite:
Just what are these dots that…
esiegel | May 14, 2010I'm a great believer in luck and I find the harder I work, the more I have of it. -Thomas Jefferson
It's the end of the semester at my college as well as at many schools across the world, and I've spent the last week or so grading final exams. And while I was doing it, I noticed something astonishing. But let me start at the beginning.
Introductory physics -- without calculus -- is one of the most notoriously challenging and rigorous classes that students pursuing a career in health, including doctors, nurses, pharmacists, veterinarians, and physical therapists, face in their college career…