[Over the past few weeks, I've collected a metric ton of cool pictures to post, but somehow have never gotten around to actually posting them. Sometimes I was too busy, sometimes too lazy, sometimes they just fell by the wayside... but I decided my computer's desktop was getting cluttered, and I'll never clean it up without some sort of incentive. I've therefore made a pact with myself to post one of the pictures with an abbreviated description every day until they're gone, thus cleaning up my desktop, showing you neat and/or beautiful pictures, and making me feel better about my work habits. Enjoy.]
IC 342 is a relatively close by face-on spiral galaxy. At 10 million light years distant, it should actually be easily visible in binoculars and would be renowned for its incredible beauty except for one small problem: we have to peer through the thick dust choking our own galaxy to see it. It’s like sitting in a smoky room and trying to see something out the window on the far side of it. Your view is obscured.
But infrared light passes through dust quite easily, so when you turn an IR telescope — like NASA’s Spitzer Space Telescope — toward IC 342, what you get is spidery magic!
[Click to embiggen.]
Holy wow! What you’re seeing is the dust in IC 342 glowing where stars are being born; giant gas clouds are star birth factories, and are shrouded in dust. The stars’ light warms the dust up and it glows. The vast complex of nebulae trace out the spiral arms, looking like a web knit by an astronomically-minded spider.
I’ve written about IC 342 twice before. Once was when the NOAO released a gorgeous image of it taken by my friend Travis Rector. Seriously, click that link. The image is spectacular.
The other time was last year when WISE, another infrared observatory, took a look at IC 342. The view is pretty similar, as you might expect — the parts of the infrared spectrum making up both images are nearly the same — but Spitzer’s mirror is twice the size of the one in WISE, so the resolution is somewhat better.
Still, the more the merrier! IC 342 is a dramatic example of a nearby face-on spiral, and there aren’t too many of those around. Even though our own Milky Way galaxy has photobombed it into relative obscurity, the prying eyes of science are pretty good at seeing through all that.
There are quite a few mysteries in astronomy; things we don’t understand. The vast majority of them are smallish in scope, things that can probably be solved with a little more work, more observations. These are more like questions than outright mysteries; things we just don’t have the answers to quite yet.
But then there are some that really are mysteries: unexpected oddities that, for now, defy explanation. One of these reared its head again recently, when observations by the ground-based Subaru and Keck observatories were combined with those from the space-based telescopes Hubble and Spitzer. It doesn’t look like much of a mystery — just a red smudge — but it pushes the boundaries of what we think the very Universe itself can do.
[Click to enbigbangenate.]
First, holy cow, what an image! Incredibly, nearly every single object in that picture is an entire galaxy, a vast collection of billions of stars. They’re also very distant; I doubt any of the bigger ones are closer than several billion light years away.
And lurking off to the side, where you’d hardly notice it, is that little red guy. Named GN-108036, it’s at the soul-crushing distance of 12.9 billion light years away. That means that the light we see here left that galaxy when the Universe was only a few hundred million years old.
As you might imagine, it may look faint, but at that distance it’s remarkable we can see it at all. But we do, because it’s amazingly luminous, perhaps the most intrinsically bright galaxy seen at that distance ever found. Of course, we don’t see too many galaxies farther away than this! And that’s part of the mystery.
IRrelevant Astronomy is a very funny web series about infrared astronomy put together by folks at Spitzer Space Telescope, and they’re all pretty good. This one is a followup for <a href="http://blogs.discovermagazine.com/badastronomy/2009/10/26/felicia-day-collides-galaxies/" target="_blank"a great video about galaxies featuring Felicia Day. They also have a couple with a guy named Wil Wheaton. Never heard of him myself, but he has promise as an actor, I think.
If you have the time, you should watch ‘em all. They’re funny, and well done, and you just might learn something.
Tip o’ the beryllium mirror to Jennifer Ouellette on Google+.
450 million light years away are two interacting galaxies. Both spirals, they are caught in each other’s gravitational claws. Already distorted and bound, eventually, to merge into one larger galaxy in a few million years, the view we have of them from Earth is both amazing and lovely… and hey: they’re punctuating their own predicament!
[Click to exclamatenate.]
Looking a lot like an exclamation point, the two galaxies together are called Arp 302 (or VV 340). This image is a combination of pictures from the Chandra X-Ray Observatory (purple) and Hubble (red, green, and blue). The bottom galaxy is a face-on spiral, while the upper one is seen more edge-on, giving the pair their typographical appearance.
Y’know, I’ve posted a lot of really pretty and cool pictures of spiral galaxies lately, and I’ve given descriptions of how they have black holes in their cores, and how the spiral arms form, and where stars are being born, and and and.
So you know what?
Boom! There you go. [Click to galactinate it.] No fancy explanations, no expounding on the ethereal beauty of dust lanes in an infrared picture from Spitzer, no lectures on anything. Just a really, really pretty picture.
I mean, I could mention how this galaxy, M63, is nearby at only 37 million light years, and how I’ve seen it myself through my telescope. But no, I won’t do that. Nothing about the prevalent short, stubby arms — called spurs — or ring of dust circling the core. And certainly nothing on how the starlight has been subtracted from the image so all you see is warm dust.
Nope. Just the picture.
Pretty, isn’t it?
Image credit: NASA/JPL-Caltech
When I was a kid, one of my favorite movies was "When Worlds Collide", about a rogue planet that collides with Earth, killing everyone (except for a few who escape on rockets).
Science fiction, right? Right?
Yeah, maybe not so much. It turns out, worlds really do collide. And we can see the shrapnel.
Binary stars are stars that physically orbit each other. They’re extremely common, but there are many types. One special kind are where the stars are very close together, like only a few million kilometers apart. Note that your average Sun-like star is well over a million kilometers in diameter, and you’ll appreciate that’s a pretty tight pair.
For centuries, scientists have wondered how stars were born. There were lots of ideas, but precious little evidence to back them up.
That’s changed recently. Oh baby, how that’s changed. Check out this gorgeous image of the star-forming compact gas cloud called GL490:
You have to click that to get the ginormous 6000 x 6000 pixel version! It’s stunning.
This image is a combination of pictures taken by the Spitzer Space Telescope and the 2 Micron All-Sky Survey, or 2MASS. Both telescopes scan the sky in the infrared, well outside what our eyes can see. In this false-color image, blue represents 2.2 microns (the reddest light our human eyes can detect is about 0.7 microns, so this is three times that wavelength), green is 3.6 microns, and red is 4.5 microns. At these long wavelengths, what you tend to see are objects that astronomers call "warm", but that’s compared to empty space. In non-geek terms, these objects are colder than 100 Kelvin: about -170°C, or -280°F!
The green glow is from PAHs, or polycyclic aromatic hydrocarbons. Again, in non-geek lingo: big molecules of stinky soot. Read More
Like astronomy? Like The Guild? Like Fwhil Fwheaton? Then you’ll love this:
This is the latest in a series of pretty funny videos from Spitzer Science Center called IRrelevant Astronomy. They’ve had lots of great folks on them, including Felicia Day, Sean Astin, and Betty White! Awesome.
In this one, Amy Okuda (Tinkerballa from The Guild) is the actor, and Wil voices the robot as well as a slightly more cheesy (not evil) version of himself. These are great videos, fun to watch, and also edumacational. I highly recommend them. Watch this one through all the way to the end…
When Galileo first turned his telescope to the sky, almost exactly 400 years ago, he could not possibly have known what he was starting.
Today, four centuries later, we’ve come a long, long way. To celebrate the anniversary of Galileo’s telescopic revolution, NASA’s Great Observatories — Hubble, Spitzer, and Chandra — have released a jaw-dropping mosaic of the very heart of the Milky Way galaxy. Behold!
This image is nothing less than a heroic effort of astronomical artistry. It’s a chunk of the sky 38 x 14 arcminutes across, or about half the size of the full Moon, and it’s aimed right into the core of our galaxy. See the bright spot just to the right of the center? Buried in there behind light years of dust and gas is the monster of the Milky Way, a black hole with four million times the mass of the Sun. But even that is dwarfed by the 400 billion solar mass heft of the entire galaxy.
There is so much going on in this image it’s hard to know where to start. But first… the Hubble images are in the near-infrared, with a wavelength a little more than twice what the eye can see (1.87 microns for those playing at home). That’s represented in the image as yellow. Spitzer contributed observations in four infrared wavelengths (3.6, 4.5, 5.8, and 8.0 microns), and those are depicted in red. Chandra sees X-rays which are normally written as units of energy, but to remain consistent with the other two images, they were at wavelengths of 0.0005, 0.00025, and 0.00016 microns, and are shown in blue.
What does all this mean? Different objects emit light at different characteristic wavelengths. Warm dust, for example, emits strongly in the infrared. Stars and warm gas emit visible and near-infrared light. Violently heated gas, affected by huge magnetic fields or shocked by colossal collisions glows in X-rays. So this image is a polychromatic view of the crowded downtown region of a bustling city: our galaxy.
You might want to look at an annotated version of this image so you can get your bearings. It’s worth it!
The huge arches of gas on the left are actually the edges of gigantic molecular clouds (dense nebulae where stars are born), lit up by the torrential blast of light from a clutch of massive stars nearby. This clot of stars, called the Arches Cluster due to the arcs it excites, can be seen as a small spot glowing blue just to the left of center in the picture. Don’t be deceived by its diminutive appearance: the Arches cluster has thousands of superstars in it, each dwarfing our Sun, and each capable of sleeting out vast amounts of radiation that lights up the gas surrounding it. Were this cluster much closer than its 25,000+ light year distance, it would blaze in our sky like a beacon. Replace the Sun in our solar system with just one of those stars, and the Earth would be fried beyond the capability of any life to survive. You might as well try living in the flame of an arc-welder.
Below and just to the left of the Arches is a clumpier, more twisted arc of gas called the Sickle. That’s a giant cavity being carved out of dense gas by the Quintuplet cluster, the pinkish glow in its center. It’s another nursery of stars like the Arches cluster, which is also blasting out light and stellar winds which eat away at the gas enveloping it. The Pistol Star resides there, perhaps one of the most massive stars in the Milky Way.
And there’s more! The blue glow on the left is from an X-ray binary called 1E1743.1-2834, what is probably a massive star being orbited by either a neutron star or a black hole. Matter is being stripped from the star and piling up outside the collapsed companion, where it gets heated up to millions of degrees and emits X-rays.
Supernovae remnants dot the image, as do stars, filaments of gas, clouds of dust, and more. This picture is an astronomer’s dream, a map of everything someone might want to visit with a starship — as long as the shields are at full strength. This image is also a map of violence, turbulence, and unrest… a typical scene, so we think, of any normal spiral galaxy like ours. And our Galaxy’s center is considered quiet by astronomers! Some are far worse.
But this is home for us. It’s a place of unimaginable fury but also astonishing beauty… and we see it now as we do because we have dared to examine the world around us, to use tools we invent to peer closer, to magnify the tiny, to extend our eyes into realms we once didn’t even know existed. And every time we do — every single time — we find more questions, more puzzles, more things to examine.
And we find art. Galileo wasn’t the first to turn his telescope to the sky, nor was he the first to record what he saw. But he was the one who made everyone see what he did, and for that, all these years later, he is owed a debt of gratitude.