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.
I somehow missed it when it came out, but the folks at IRrelevant Astronomy have a great video about how stars die, and it has Sean Astin (Samwise!) and Sandeep Parikh (Zaboo!).
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 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.
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.
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. (more…)
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. (more…)
Phil Plait, the creator of Bad Astronomy, is an astronomer, lecturer, and author. After ten years working on Hubble Space Telescope and six more working on astronomy education, he struck out on his own as a writer. He's written two books, dozens of magazine articles, and 12 bazillion blog articles. He is a skeptic and fights the abuse of science, but his true love is praising the wonders of real science.
The original BA site (with the Moon Hoax debunking, movie reviews, and all that) can be found here.
Contact me: The Bad Astronomer "at" gmail "dot" com
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