Astronomy
esiegel | June 30, 2012"Don't go around saying the world owes you a living. The world owes you nothing. It was here first." -Mark Twain
So, you've been around a while, seen all sorts of things, and learned an awful lot about the world, solar system and Universe that we live in. But how well do you know it, really?
Image credit: NASA / Lunar and Planetary Laboratory.
To scale and in order, these are the eight planets you know so well. There are the four rocky worlds of our inner solar system: Mercury, Venus, Earth, and Mars, and the four gas giants that dominate the outer solar system: Jupiter, Saturn, Uranus, and…
esiegel | June 26, 2012"We came all this way to explore the Moon, and the most important thing is that we discovered the Earth." -Bill Anders, Apollo 8 astronaut
From hundreds of miles up, the International Space Station speeds around the Earth, completing 18 orbits a day, looking down on us and returning some absolutely fabulous images.
Image credit: Fyodor Yurchikhin and the Russian Space Agency Press Services, of Greenland from the ISS.
But what you may not appreciate is that my favorite images taken from the ISS weren't taken by American Astronaut Don Pettit (better known as @astro_Pettit), but rather by a…
esiegel | June 22, 2012"Some prophecies are self-fulfilling
But I've had to work for all of mine
Better times will come to me, God willing
Cause I can't leave this world behind" -Josh Ritter
You sure can't leave this world behind. At least, not very easily. The reason for it, of course, is gravity.
Image Credit: Physclips, via the University of New South Wales' School of Physics.
Here on the surface of the Earth, the gravitational potential well is pretty large; large enough that there's no easy way off. Sure, you can pour a huge amount of energy into a rocket to try and overcome this gravitational potential…
esiegel | June 19, 2012"Soon the earth will tilt on its axis and begin to dance to the reggae beat to the accompaniment of earthquake. And who can resist the dance of the earthquake, mon?" -Peter Tosh
Every year, there are two special days where every place on Earth receives the same amount of sunlight -- 12 hours -- split evenly between night and day: the equinoxes!
Image credit: timeanddate.com.
Like all known objects that revolve around another due to gravity, the Earth rotates along its journey around the Sun. But on those two days of the equinox (from the Latin, meaning "equal nights"), the Earth's axis-of-…
esiegel | June 15, 2012"I would rather be adorned by beauty of character than jewels. Jewels are the gift of fortune, while character comes from within." -Plautus
When it comes to astronomy, there's no doubt that I've got a northern hemisphere bias. It's no surprise, of course; I live here. And while I often write about the skies that we all share, astronomy has a historical bias in favor of the northern hemisphere. You know this, too. Ask most people to name one single thing in the night sky, and you're most likely going to end up with this.
Image credit: Rich Richins of http://www.enchantedskies.net/.
The Big…
esiegel | June 14, 2012"Everyone is a moon, and has a dark side which he never shows to anybody." -Mark Twain
Back before the telescope was invented, Saturn was known as the Old Man of the Skies. The slowest-moving of the naked-eye planets, it's the only one that would reliably be in nearly the same location, year after year. You can find it all summer, after sunset, by following the "arc" of the handle of the big dipper all the way until you run into the brightest northern-hemisphere star, Arcturus, and then speeding on to the very bright Spica. Saturn is right next door.
Image credit: EarthSky.org.
But…
esiegel | June 12, 2012"I went into a clothing store, and the lady asked me what size I was. I said, 'Actual'. I'm not to scale." -Demitri Martin
When you look out at the Universe, what you can see is limited, at the most fundamental level, by the size of what you look with. This is why you can see dimmer objects at night -- when your pupils are dilated -- than you can when your pupils are constricted.
Image credit: National Institute of Health.
This same principle that applies to your eyes applies to telescopes as well. As telescopes have grown in size, so has our ability to see deeper into the Universe, as we…
esiegel | June 8, 2012"Building one space station for everyone was and is insane: we should have built a dozen." -Larry Niven
Here on the solid ground of the Earth, the Sun and Moon rise and set on a daily basis. During the hours where the Sun is invisible, blocked by the solid Earth, the stars twirl overhead in the great canopy of the night sky.
Image credit: Chris Luckhardt at flickr.
In the northern hemisphere, they appear to rotate around the North Star, while in the southern hemisphere, the stars appear to rotate about the South Celestial Pole. The longer you observe -- or for photography, the longer you…
esiegel | June 6, 2012"You don't use science to show that you're right, you use science to become right." -Randall of xkcd
In January of 2008, I began writing this blog, Starts With A Bang, both for myself and for all of you, because we all have something in common.
Image credit: © Stéphane Guisard, "Los Cielos de Chile", via astrosurf.com.
The same planet, the same heavens, the same laws of nature and the same Universe are something that we all have in common. And all of us, no matter how intrinsically smart, talented, or brilliant our instincts are, come into this world knowing absolutely nothing about it.
But…
esiegel | June 5, 2012
Image credit: NASA's Solar Dynamics Observatory.
Good luck, clear skies and great viewing for everyone out there trying to see the Venus Transit!
Update 1: Watch the event live here, or watch the embedded NASA video stream, below:
Live video from your Android device on Ustream
Update 2: here are the results of my Transit "expedition", where I didn't get any good photos directly through my protective eyegear, but the binocular trick paid off handsomely.
Image credit: Kelly Montgomery, from my crummy binoculars duct taped onto a tripod.
No, really, that's what this is. For those of you who'…
esiegel | June 1, 2012"The moon shuts off the beams of the sun as it passes across it, and darkens so much of the earth as the breadth of the blue-eyed moon amounts to." -Empedocles, ~450 B.C.
Less than two weeks ago, I saw my first annular eclipse, with some spectacular results at the moment of maximum eclipse.
From my first eclipse expedition, to False Klamath Cove, on the coast in northern California.
This happens, of course, because -- from our point of view -- the Moon appears to pass in front of the Sun, blocking a fraction of the light coming from it.
Image credit: NASA / Solar Dynamics Observatory.
And…
milhayser | June 1, 2012
On Dynamics of Cats, Steinn Sigurðsson sifts through Hubble's vast catalog of stars, gas, and galaxies, looking for a diamond in the rough. Many images captured by the Hubble Space Telescope have never really been looked at; Sigurðsson says "In some cases the PI died before doing so. More usually these are engineering test images, or 'parallel images,' where a second camera was set to take images of wherever it happened to be pointed." The European Space Agency wants your help to search through these pictures. In 2004, Hubble resolved the famous Ultra Deep-Field with 10,000 galaxies across…
esiegel | May 31, 2012"Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space." -Douglas Adams
Here inside the Milky Way galaxy, all you need are some dark skies and a decent set of eyes, and you'll be greeted of a spectacular, close-up view of the galaxy you inhabit.
Image Credit: ESO / Stephane Guisard, from http://www.astrosurf.com/sguisard/
But getting a handle on the size and scale of our Milky Way? Perhaps paradoxically, that's a question we're still figuring out the answers…
esiegel | May 28, 2012"Everyone must leave something behind when he dies, my grandfather said. A child or a book or a painting or a house or a wall built or a pair of shoes made. Or a garden planted. Something your hand touched some way so your soul has somewhere to go when you die, and when people look at that tree or that flower you planted, you're there." -Ray Bradbury
Today is Memorial Day here in the United States, where we honor all the soldiers who have fought and fallen for our country. The peace and prosperity that I have enjoyed my entire life is because of a price paid, many times over, mostly by people…
esiegel | May 26, 2012"This seems to be the law of progress in everything we do; it moves along a spiral rather than a perpendicular; we seem to be actually going out of the way, and yet it turns out that we were really moving upward all the time." -Frances Willard
As spring gives way to summer here in the Northern Hemisphere, one of the most beloved sights of the night sky becomes ever more prominent: the Big Dipper.
(Image credit: NASA, ESA, Z. Levay (STScI) and A. Fujii.)
These seven bright stars shine high above the horizon after sunset, and will continue to do so over the rest of the Spring and all Summer…
esiegel | May 24, 2012"Be still when you have nothing to say; when genuine passion moves you, say what you've got to say, and say it hot." -D.H. Lawrence
Here in our Solar System, the planet closest to our Sun is Mercury, speeding around in a complete orbit once every 88 days, with daytime temperatures reaching a sweltering 400° C, or around 800° F.
(Image credit: NASA / Johns Hopkins University / Carnegie Institute of Washington.)
With its size, temperatures, and distance from the Sun, Mercury has had its entire atmosphere stripped away by the Sun. And while these temperatures might seem hot, in comparison with…
catdynamics | May 23, 2012Just a quick heads-up for those who don't know yet: there is closed group "Astronomers" on facebook. It is by invitation only, ie some existing member must add any new member. You must have an fb account to be added.
The group has about 4,000 members, most all professional astronomers from around the world.
There is some interesting discussion going on in that group and some useful info being passed around.
The closed group feature seems to work well for some combination of intensity of topic focus and size - not too small, not too big.
'fraid I wouldn't tell how to monetize the feature…
esiegel | May 23, 2012"As always on this boulevard, the faces were young, coming annually in an endless migration from every country, every continent, to alight here once in the long journey of their lives." -Brian Moore
Even the Universe experiences a "great migration" every now and again, where giant, massive globules of interstellar gas are blown thousands of light years across the galaxy by their hot, star-forming surroundings.
(Image credit: R. Jay GaBany of cosmotography.com.)
And if I do say so myself, in the case of the Cone Nebula, it looks like the classic "V" pattern that migrating birds engage in. Of…
esiegel | May 21, 2012"A little more persistence, a little more effort, and what seemed hopeless failure may turn to glorious success." -Elbert Hubbard
I've had the great fortune in my life to see a great many wonderful things with my own eyes, including the rings of Saturn, the phases of Venus, a couple of faint, distant galaxies, and a large number of sunsets, sunrises, and lunar eclipses. But as far as solar eclipses go, I missed the only realistic opportunity I ever had to see -- as Cara Beth Satalino would say -- that
Shimmering Thing.Back in 1994, an annular solar eclipse happened just 300 miles from where I…
esiegel | May 8, 2012"There's nothing that cleanses your soul like getting the hell kicked out of you."
-Woody Hayes
There's no doubt that we lucked out when it came to the formation of our Solar System.
Image credit: Michael Pidwirny, retrieved from cosmosportal.org.
Our inner Solar System, where temperatures are ideal for liquid water and life-as-we-know-it, is full of rocky planets and devoid of any gas giants for many hundreds of millions of miles. But, as we know all too well from the last twenty years of finding exoplanets, this isn't the only way it could have turned out.
In fact, of the some 2,300…