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"Some painters transform the Sun into a yellow spot, others transform a yellow spot into the Sun." -Pablo Picasso
But the Sun will not always be a bright spot. Though it has shone for billions of years already, and will continue to shine for billions of years more, it's currently doing this by burning its hydrogen fuel -- through the fires of nuclear fusion -- into the heavier element of helium.
Image credit: retrieved from UFO et Science.
But after about 10-12 billion years total, all the hydrogen that can be burned in the core will be used up! (There will still be hydrogen in the outer…
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"Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity - in all this vastness - there is no hint that help will come from elsewhere to save us from ourselves. It is up to us." -Carl Sagan
Here on our planet, this is the one day that we take out of the year to stop and appreciate just how amazing the natural world really is, and how fortunate we are to have the Earth that we have. A wonderful but sad reminder of how fragile it is, and how quickly and easily we can affect it, comes through John Prine's great song,
Paradise.Here on our planet, there are countless…
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"April is the cruellest month, breeding
Lilacs out of the dead land, mixing
Memory and desire, stirring
Dull roots with spring rain." -T. S. Eliot
Of course you all know the refrain, "April showers bring May flowers," but there's one April shower that brings fireballs instead: the Lyrids!
Image credit: John Chumack, retrieved from Bob King.
Like all meteor showers, the Lyrids come from a comet's dust trail that forms a great ellipse with respect to our Solar System. Once per year, the Earth, in its orbit around the Sun, passes through this dusty debris. When this happens, the Earth, moving…
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"Science progresses best when observations force us to alter our preconceptions." -Vera Rubin
I want you to think about the Universe. The whole thing; about everything that physically exists, both visible and invisible, about the laws of nature that they obey, and about your place in it.
It's a daunting, terrifying, and simultaneously beautiful and wondrous thing, isn't it?
Image credit: NASA, ESA, S. Beckwith (STScI) and the HUDF Team.
After all, we spend our entire lives on one rocky world, that's just one of many planets orbiting our Sun, which is just one star among hundreds of billions…
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"Truth is mighty and will prevail. There is nothing wrong with this, except that it ain't so." -Mark Twain
"It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong." -Richard Feynman
Every day that you set forth in the world is a new opportunity to learn something about it. Every new observation that you make, every new test you perform, every novel encounter or piece of information you pick up is a new chance to be a scientist.
How so?
Image credit: Alan Chen.
You have a conception of how things work in this world…
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"You never need think you can turn over any old falsehoods without a terrible squirming of the horrid little population that dwells under it." -Oliver Wendell Holmes
As an astrophysicist, I get sent all sorts of (unsolicited) novel ideas and theories claiming to overturn everything from special relativity to quantum theory to the Big Bang. But the biologists get one very special type that I don't, that I was fortunate enough to have shared with me. This is not a case of physicists vs. biologists; on the contrary -- as the Be Good Tanyas might tell you -- this is what it sounds like
When Doves…
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"If we knew what it was we were doing, it would not be called research, would it?" -Albert Einstein
Our galaxy is but one among hundreds of billions in the cosmos, nearly all of which contain supermassive black holes at the center. Ours happens to be "only" a few million times as massive as our Sun, as well as quiet.
Image credit: ESO, R. Genzel et al. at MPI fur Extraterrestrische Physik.
In other words, our galaxy's supermassive black hole is behaving right now, by not viciously shooting off high-energy jets of particles and light at some poor, innocent passers-by.
But other galaxies are…
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"We were left with a picture of part of the sky with no stars or galaxies, but it still had this infrared glow with giant blobs that we think could be the glow from the very first stars." -John Mather
When you look out at the night sky, you're limited by the light pollution from your surroundings, the imperfections of our atmosphere, the light-blocking gas and dust throughout the interstellar and intergalactic medium, and the capabilities of your eyes. Still, what one can see is truly a sight to behold.
Image credit: IronRodArt - Royce Blair of NightScapePhotos.com.
What if you didn't have…
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"You cannot, in human experience, rush into the light. You have to go through the twilight into the broadening day before the noon comes and the full sun is upon the landscape." -Woodrow Wilson
Without a doubt, one of the most spectacular light shows of the cosmos happens when stars burn out -- reaching the end of their normal life cycle -- and die in a great supernova explosion. We've spoken in the past about the main ways that these stars die. Either a very massive star -- something more than ten times as massive as our Sun -- reaches the end of its nuclear fuel, and its core collapses,…
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"It's so fine and yet so terrible to stand in front of a blank canvas." -Paul Cezanne
All over the world, hundreds of millions of families are getting together this weekend for a variety of reasons. And a large number of them will have, as part of their nature, a big announcement made. Depending on the announcement and the family, reactions will vary greatly. As you keep this in mind, I'd like you to listen to the French band, Air, and their unheralded electronica masterpiece,
Talisman.
There are many possible answers to the following question, and there is no right or wrong answer.…
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"Well you run and you run to catch up with the Sun but it's sinking,
racing around to come up behind you again.
The Sun is the same in a relative way but you're older,
shorter of breath and one day closer to death." -Pink Floyd
For the last four-and-a-half billion years, the Earth has spun on its axis, orbiting its parent star: our Sun. Today, our home planet looks something like this.
Image credit: Reto Stöckli, Nazmi El Saleous, and Marit Jentoft-Nilsen, NASA GSFC.
Looking at our world, even from outer space, you see some very familiar features that we think of as essential parts of our…
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"...the publisher wouldn't let us call it the Goddamn Particle, though that might be a more appropriate title, given its villainous nature and the expense it is causing."
-Leon Lederman, author of The God Particle
The Higgs Boson: you know the deal. It's the last undiscovered particle in our current picture of all the fundamental particles in the Universe.
Image credit: Fermilab, retrieved from eurekalert.org.
If we can find it, we'll either have a big clue as to what the next step to take in physics will be, or we'll be forced to admit that physics works too well, and many of the great…
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"I think a strong claim can be made that the process of scientific discovery may be regarded as a form of art. This is best seen in the theoretical aspects of Physical Science... The theory of relativity by Einstein, quite apart from any question of its validity, cannot but be regarded as a magnificent work of art." -Sir Ernest Rutherford
Einstein's theory of relativity -- and in particular, the notion that no form of matter or energy can exceed the speed of light in vacuum -- has been one of the most thoroughly tested and most successfully robust scientific theories of all time. Have a…
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"A galaxy is composed of gas and dust and stars - billions upon billions of stars."
-Carl Sagan
Perhaps the most striking feature of the night sky under truly dark conditions isn't the canopy of those thousands of points of light, but rather the expanse of the Milky Way, streaking across the entire night sky.
Image credit: Richard Payne, retrieved from astro.wisc.edu.
With an estimated 200-400 billion stars contained within our island Universe, the Milky Way is just a regular, run-of-the-mill spiral galaxy compared to the rest of what's out there.
But it's our home. And, despite the…
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"[The black hole] teaches us that space can be crumpled like a piece of paper into an infinitesimal dot, that time can be extinguished like a blown-out flame, and that the laws of physics that we regard as 'sacred,' as immutable, are anything but."
-John A. Wheeler
To an astronomer on any other world, the most important object in our Solar System wouldn't be the Earth, but rather our Sun. Just one example of the hundreds of billions of stars in our galaxy, our Sun is a G-type star, burning at around 6,000 Kelvin and with a lifetime of around 10 billion years.
But stars come in a great variety…
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"Think binary. When matter meets antimatter, both vanish, into pure energy. But both existed; I mean, there was a condition we'll call 'existence.' Think of one and minus one. Together they add up to zero, nothing, nada, niente, right? Picture them together, then picture them separating--peeling apart. ... Now you have something, you have two somethings, where once you had nothing." -John Updike
Looking out at our Universe, at the myriad of stars, galaxies, and, well, "stuff" in our Universe, it's hard not to ask yourself where it all came from.
Image credit: Rogelio Bernal Andreo, retrieved…
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"You will be able to program a robot to follow a track on the ground and manipulate a hand. You can also write little programs that will give the robots goals." -Bill Budge
Ever since the very first robots were conceived, the robot apocalypse -- or a time where the robots will become intelligent enough to rise up and overthrow their human creators -- has gripped the popular imagination. Have a listen to Wyclef Jean's song,
Apocalypse,
while you ponder the implications of this great find.
A creative artificial intelligence (AI) engine, Angelina, can design and create its own videogames…
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"Deep into that darkness peering,
long I stood there, wondering, fearing,
doubting, dreaming dreams no mortal
ever dared to dream before." -Edgar Allen Poe
When you look out into the darkness of a moonless, unpolluted night sky, you'll of course notice that it's full of stars, planets, and the occasional extended object.
Image credit: Bob King at AstroBob.
But you'll also notice that there are plenty of regions that -- other than a few stars -- don't really have very much going on. One such region, visible in the southern skies pretty much year-round, is the constellation of Sextans.…
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"When I had satisfied myself that no star of that kind had ever shone before, I was led into such perplexity by the unbelievability of the thing that I began to doubt the faith of my own eyes." -Tycho Brahe
When stars reach the end of their lives, there are many possible fates that they can have. Among the most spectacular, however, are stars that end their lives by going supernova, where a single star can outshine even an entire galaxy for a brief moment in time.
Image credit: SN 2006gy, X-ray by NASA / CXC, Nathan Smith, Weidong Li et al., IR by PAIRITEL / Lick / U.C. Berkeley / J.Bloom,…
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"To use Newton's words, our efforts up till this moment have but turned over a pebble or shell here and there on the beach, with only a forlorn hope that under one of them was the gem we were seeking. Now we have the sieve, the minds, the hands, the time, and, particularly, the dedication to find those gems--no matter in which favorite hiding place the children of distant worlds have placed them."
-Frank Drake and Dava Sobel
Looking up at the canopy of stars in the night sky, and realizing that each point of light is a star system not so unlike our own, one can't help but wonder about those…