Astronomy
esiegel | November 10, 2009Yesterday, I talked about why we should look for a history of life on Mars, and had an article for SEED magazine to that effect. After all, we've made some recent geological finds that are surefire indicators of past liquid water on Mars, and possible indicators of past life.
While most of the article was about Mars' history as a planet and the argument that in the past, it was much more Earth-like than it is today, I had one sentence that appears to have touched off a firestorm in the comments:
I don't know whether there was life on Mars or not, but based on what I know about abiogenesis…
esiegel | November 9, 2009The Mars Polar Lander cost the average American the price of half a cheeseburger. A human lander would cost the average American more -- perhaps even ten cheeseburgers! So be it. That is no great sacrifice.
-JONAH GOLDBERG, National Review Online, May 3, 2000
This week, Seed Magazine is doing a special on extraterrestrial life in the Universe. They cover a lot of ground, including whether life would necessarily look like life on Earth, where the likely places are to find it, and endeavors towards that end.
And they approached me to write an article for them about Mars. An excerpt is below:…
pontiff | November 6, 2009I get a lot of press releases forward to me which usually get forwarded directly into my gmail archive. But this one I'm happy to pass along: Third Man Records is releasing A Glorious Dawn. You know the Carl Sagan remix (w/ guest appearance of the Hawkmeister) that I've been looping over and over again while I work:
Third Man Records is over the moon to announce the 7-inch release of "A Glorious Dawn" on November 9th.
...
The release is timed to coincide with the 75th anniversary of Sagan's birth. Also happening that day is a reception in United States' Congress with speeches by senators,…
esiegel | November 6, 2009It's hard to believe that until 1929, we were pretty sure that the Universe consisted entirely of our galaxy, and everything else was inside of us.
Hard to believe that you can look at something like this and not think it was another galaxy like our own, isn't it?
Yet when you look in the visible light -- which is all they knew how to do back then -- this is what the pinwheel galaxy (above) looks like through a modern advanced amateur telescope.
Is it really so clear to your naked eye that this image is so different from the one below?
Believe it or not, this image is of a planetary nebula…
rallain | November 5, 2009Very simply, parallax is an apparent motion of an object due to a change in observation position. Let me start with an example. Here are two photos. I took a picture of the cabinet in the background from two slightly different positions. In the foreground is a clone trooper that did not actually move.
I added the dotted line so you could see how the clone trooper appeared to change positions with respect to the background. Here is a diagram of the camera in the two positions along with the toy.
Since the camera changed positions, the object that is closer appears to have moved with…
esiegel | November 2, 2009My heroes had the heart to lose their lives out on a limb,
And all I remember is thinking, "I want to be like them!" --Gnarls Barkley
And here's a new discovery (to me): the Violent Femmes version to help you through your post-Halloween Monday:
The Ares I-X rocket has been all over the news recently. I'm not sure that the news coverage sufficiently showcases how impressive this rocket actually is. Sure, you've all seen a picture of the rocket on the launchpad.
Yes, the rocket has a long history. Yes, it's nearly twice as high as the space shuttle (at a whopping 327 feet, or 99.7 meters).…
esiegel | October 30, 2009I had a dream, which was not all a dream.
The bright sun was extinguish'd, and the stars
Did wander darkling in the eternal space... --Lord Byron, Darkness
Or, in other words, boo!
Halloween, believe it or not, is an astronomical holiday! The two solstices and two equinoxes are obvious astronomical holidays, since they correspond to the days of greatest, least, and equal daylight/night everywhere in both the Northern and Southern Hemispheres.
But halfway in-between each solstice and equinox lie the cross-quarter days. Just as we still mark the winter solstice (almost) with Christmas and the…
esiegel | October 29, 2009The farther backwards you can look, the farther forwards you are likely to see. -- Winston Churchill
Sometimes, we point our most powerful telescopes at the sky, peering as deeply as we possibly can, hoping to shed some light on what the Universe was like oh-so-long ago, as close to the big bang as we can. The Hubble Space Telescope can get us distant galaxies as they were just a few billion years after the big bang.
But Hubble still has never seen one of the elusive, Holy Grails of astronomy: a metal-free star.
You see, immediately after the big bang, the Universe was filled with protons…
esiegel | October 26, 2009Perhaps you've been following my ongoing series on dark matter. Perhaps, like many, you're still skeptical. After all, it's not like we've gone and made it in a lab or discovered it in an experiment. 15 years after David Weinberg composed the Dark Matter Rap, we still don't know exactly what dark matter is.
But there's a whole lot that we do know about it just from looking out at the Universe.
You see, there are a whole bunch of scales we can see, from galaxies to clusters to superclusters and the large-scale structure of the Universe as a whole.
And-- since the big bang happened just under…
esiegel | October 26, 2009I do not know what I may appear to the world; but to myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me. --Isaac Newton
Can you imagine what good ol' Sir Isaac would've said, done, and thought if he could've looked up at the stars and seen what we see today?
Image credit: Astronomy Picture of the Day.
Just inspiring, awesome, and yes, this was all undiscovered to him and subsequent scientists for centuries. The…
esiegel | October 23, 2009Seed Magazine (which I've written for) has just put out a space slideshow: Traveling Through Time and Stars.
Michael Benson gives an account -- in words and pictures -- of a journey outwards, from nearby stars to nebulae to other galaxies to clusters of galaxies. The pictures alone are worth having a look at.
Beautiful? I don't know that that even begins to describe it, but it certainly helps give me a great perspective on what these different regions look like.
The idea of zooming out and looking at things on larger and larger scales really appeals to me. In fact, I think the slideshow…
esiegel | October 19, 2009If people around you aren't going anywhere, if their dreams are no bigger than hanging out on the corner, or if they're dragging you down, get rid of them. Negative people can sap your energy so fast, and they can take your dreams from you, too.
--Earvin "Magic" Johnson
As far as science goes, we all have our own dreams. For me, it's to understand the largest scales in the Universe: the most massive structures, the highest energies, and the earliest times of existence.
Particle physicists are also after understanding the Universe at its highest energies, and that's one of the primary goals…
esiegel | October 14, 2009It's only natural to wonder why things are the ways that they are. Take a look at our Solar System, for example.
A central bulge with planets, moons, and whatnot moving in a disc around it. Is this the way things have to be? My friend Rich, a chemist, asks:
It seems that all the objects in our solar system orbit the sun in nearly the same plane. Why is that? Why doesn't the solar system have spherical symmetry?
In particular, Rich wants to know why our Solar System doesn't look more like this:
Our Solar System is definitely not shaped like a sphere; it definitely is a bulge at the center…
esiegel | October 13, 2009
Barney: Next they're gonna show my movie.
Bart: You made a movie ?
Barney: I made a movie? I wonder why there was a picture of me on the cover of Entertainment Weekly.
Earlier this year, a documentary film challenge was issued internationally. The goal was to make a movie about one of this year's two themes: hope or fear.
A group of Oregon filmmakers, The Cingulate System, called me up at work and asked if they could interview me for their film about Dark Matter. The challenge was to make a documentary, from scratch, in under a week. The film premiered April 8th right here in Portland…
esiegel | October 12, 2009My Very Educated Mother Just Served Us Nine Pickles.
--Children everywhere, up until very recently
Taking a look at the new ring discovered around Saturn made me realize something. Most of us don't realize how full of crap our Solar System is.
I don't mean planets, or moons, or comets or asteroids, although there are certainly plenty to go around. A brief recap of what happened around Saturn first. Saturn has seven glorious, inner rings that we're familiar with, that make it a magnificent sight for skywatchers everywhere.
If you look closely at this image, you will see a few white dots in…
ejohnson | October 12, 2009
Early Friday morning, NASA's Lunar Crater Observation and Sensing Satellite, or LCROSS, collided with the Moon at a speed of 5,600 miles per hour, in hopes that debris stirred up by the impact would provide valuable data about how much water might be hidden in craters near the lunar poles. While the plume of debris did not rise high enough to be visible to hopeful observers watching through telescopes, NASA scientists were able to collect a wealth of non-visual data. When the analysis of the data is complete, it could help them to determine whether enough water is present to sustain lunar…
esiegel | October 9, 2009One ring to rule them all,
one ring to find them.
One ring to bring them all
and in the darkness bind them. --J.R.R. Tolkien
Of course we're all familiar with the planet Saturn. Gas giant, many moons, and, of course, its prominent rings:
Note that word, rings. Sure, at a distance, it may just look like one elongated ring.
But our tools for measurement are better than our mere naked eyes. Saturn was known, very clearly, to have seven separate rings, many of which are separated by large moons in their orbits.
But very recently, a team of astronomers from Maryland and Virginia have discovered…
esiegel | October 6, 2009You're sweet as a honey bee
But like a honey bee stings
You've gone and left my heart in pain
All you left is our favorite song
The one we danced to all night long
It used to bring sweet memories
Of a tender love that used to be
Now it's the same old song
But with a different meaning
Since you been gone --The Four Tops
Those of you who've been with me since the start of our current series on Dark Matter, including parts I, II, III, and 3.5, know that I'm a big proponent of dark matter. I think, based on everything that we know, that it is the simplest, easiest, and most likely explanation for…
esiegel | October 5, 2009Though my soul may set in darkness,
It will rise in perfect light,
I have loved the stars too fondly
To be fearful of the night. --Sarah Williams
Everyone knows how you see things during the day: sunlight makes it possible. Delivering huge amounts of visible light to the entire "day" side of the planet, everything becomes illuminated to human eyes.
But things change rapidly once the Sun goes down. Even with a full Moon in the sky (like last night), the amount of light reaching the Earth at night is over 100 trillion times less than during the day.
Still, we have a great pair of eyes, and…
pontiff | October 1, 2009Via physicsandcake, on some days I wish I was as dorky and as elegant as Carl Sagan:
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every…