Multiple-Intelligences Neural Interfacing Optimization Node
I'm a geek. No. Really. Really geeky. And I write poetry. And I read poetry. I'm an English teacher to-be.
(via APOD: 2012 September 27 - Stars and Dust Across Corona Australis)
Stars and Dust Across Corona Australis
Image Credit & Copyright: Marco Lorenzi (Glittering Lights)
Corona Australis is the Southern Crown. (Here in the northern hemisphere, we have Bootes holding Corona Borealis in the night sky. Bootes, the herdsman, is the constellation that Arcturus is in. Remember “arc to Arcturus and spike to Spica”. Spica is in Virgo.)
In any case, there’s a crown in the skies of the southern hemisphere too, and that’s where you can see this interesting collection of dust, along with a globular cluster…at least in the same line of sight.
The blue light you see in the nebulae is from the stars embedded in the dust, and is being reflected back toward us. Blue light scatters more readily in the dust of the interstellar medium, so more blue than red is being bounced off the “grains” (think something the size of soot) back at us.
The dark areas are where the dust is so thick between our point of view and the star field that we can’t see through it in visible wavelengths. An infrared image would see through it, and into it, to see what’s going on.
The cloud of dust creating this nebular complex is about 500 light-years away, but the globular cluster in the upper left of the image, while appearing close, is actually about 30,000 light-years away, far beyond the dust and stars of the nebulae. They’re very old, gravitationally bound collections of stars that orbit the galaxy, but not necessarily in the galactic plane. This one is NGC 6729.
(via APOD: 2012 September 12 - M7: Open Star Cluster in Scorpius)
Image Credit & Copyright: Dieter Willasch (Astro-Cabinet)
Look toward the center of the galaxy, and what do you find?
As in this picture, taken of the M7 open star cluster in Scorpio, you’re sometimes treated to a glimpse of young stars in loose formations (only 200 million years old!), with interstellar gas and dust creating very obvious dark nebulae around it, and those dark nebulae are obvious because the background is so completely filled with the millions of stars between us and the galactic center.
So, three big things going on here:
1) An open cluster of stars. These have formed out of the same cloud of interstellar gas and dust and are usually very young, since the tight clustering indicates an early generation of stars from a dust-cloud, who tend to be more massive and energetic, meaning they die off sooner, too. (This is compared to globular clusters, which are all very old.)
2) Dark nebulae in the surrounding areas, some of which may be part of the cloud that originally served as the nursery for this open cluster. (Take a look at the Eagle Nebula in Orion or at the multi-wavelength picture I posted of a star cluster being born in the Large Magellanic Cloud to see this process in early stages.) Of course, it could just be other dust in the line-of-sight of M7.
3) The millions of background stars, unrelated to the cluster, sitting between us and the center of the galaxy. It’s insanely dense with stars, gas, and dust when we look that way, since we’re a spiral galaxy with star formation happening all the time.
(via APOD: 2012 September 9 - Wisps Surrounding the Horsehead Nebula)
Image Credit & Copyright: Star Shadows Remote Observatory
See the little horse-head? That’s the Horsehead Nebula. It’s not exactly a little nebula off by itself. It’s part of a larger molecular cloud complex in Orion.
This show was taken with a very long (7 hour) exposure of hydrogen-alpha in red and overlaid on a broadband (full color) image taken over a 3 hour interval to capture the background star field.
(via APOD: 2012 August 28 - Colorful Clouds Near Rho Ophiuchi)
Image Credit & Copyright: Tom O’Donoghue
Oooh! A lesson in the forms and varieties of nebulae all in one picture. OK, so there are three main kinds of nebulae:
- Reflection
- Emission
- Dark
They’re produced by different processes too, so here’s what’s going on above:
Rho Ophiuchi, the bright blue star in the center of the top blue nebula is emitting regular light that is being scattered off the dust in the nebular clouds. Dust particles tend to scatter blue light more than any other wavelength of light, so the reflected light from the nebula is blue. Hence, reflection nebulae look blue.
To the lower-right, you can see Sigma Scorpii, a bright blue star in the middle of a red nebula. When the ultraviolet radiation from a star hit gas clouds, made mostly from hydrogen, they ionize the gas, stripping the electrons off the atoms. Atoms don’t stay that way forever, though, and they have a tendency to pull an electron back at some point, de-ionizing themselves. When that happens, it releases energy in the form of electromagnetic radiation, usually as red light. We see the light being emitted from the gas as it de-ionizes.
Finally, in all those spots, mostly in the middle of the picture, where you might be worried that the photographer’s camera has some sensing issues, where we’re not seeing any background starlight, or really anything at all, those are areas where there’s too much dust, in the way, making a dark spot in the sky.
Oh, a couple other things:
- Big, bright, red supergiant Antares in the lower middle is so red that even it’s reflected light is yellow-red.
- M4 is the globular cluster just to right of Antares, an ancient relic of the universe, as are all the globular clusters we’ve ever seen. They orbit the Milky Way and are generally around 12-13 billion years old.
Boy do I love this astronomy stuff.
(via APOD: 2012 August 5 - IC 1396: Emission Nebula in Cepheus)
Image Credit: Digitized Sky Survey, ESA/ESO/NASA FITS Liberator
Color Composite: Davide De Martin (Skyfactory)
In the constellation Cepheus, the King (which actually looks like a child’s drawing of a house when you connect the main stars), IC 1396 glows as the gas and dust within the stellar nursery is radiated by the newly-born stars, especially the big bright one in the center here.
This impressive compilation comes from black-and-white narrow-band shots composited.
They’re all from the Mt. Palomar Observatory down near San Diego.
Adding some extra interesting detail are the obscuring clumps of dust clouds blocking light.
(via APOD: 2012 June 1 - A Sagittarius Triplet)
At the top is NGC 6559, separated from the Lagoon Nebula by a dust lane, with M8 dominating the frame (that’s the Lagoon’s Messier designation), and the multi-colored Trifid Nebula, M20, off to the right.
All three of these are star-forming regions in Sagittarius, the centaur archer shooting his arrow at Antares, the heart of Scorpio. It happens that Sagittarius sits over the central Milky Way, so there is a lot of dust and gas.
As a final bonus, M21, an open star cluster, is sitting just above the Trifid. (The Trifid, in case you are wondering, is named as such because it shows off all three types of nebulae: emission (red), reflection (blue), dark (lack of light, obscured by dust).)
Image Credit & Copyright: Martin Pugh
(via APOD: 2012 May 16 - Star Formation in the Tarantula Nebula)
Holy! A wonderful mosaic composition of Hubble data is assembled here. Even at a small size, it is impressive, but blow it up…and prepare to have trouble containing the awesome.
This is the Tarantula Nebula, out in the Large Magellanic Cloud, a satellite galaxy to our own Milky Way. It’s actually the most active star-forming region in the entire Local Group of galaxies (our home cluster). If it was as close as the Orion Nebula, it would cover half the sky!
There’s a whole ton of stuff going on here. The pinks and reds are gas from emission nebulae (excited hydrogen de-ionizing and releasing electromagnetic radiation), but there are remnants of supernovae in here (as you might expect, when you birth a lot of stars, some of them die off rather quickly) and dark nebulae (dust that’s in-between you and a light source, creating a dark patch, but which is, in combination with the gas, quite useful for starting more stellar formation).
Happy 22nd anniversary of Hubble’s launch, indeed!
Image Credit: NASA, ESA, ESO, D. Lennon (ESA/STScI) et al., and the Hubble Heritage Team (STScI/AURA)
(via APOD: 2012 February 12 - Orion in Gas, Dust, and Stars)
Just 75 light-years worth of the Giant Orion Molecular Cloud Complex here. The big bright objects on the left of the image are the belt stars of Orion.
I’m willing to bet if you just look for a few moments, you’ll notice the Horsehead Nebula; its nearby companion, the Flame Nebula; M42, the Orion Nebula, with its newborn stars throwing off powerful radiation, causing the gas to glow and pushing the dust around; and, finally, its neighbor, the Running Man with its bright blue stars in a reflection nebula.
Image Credit & Copyright: Rogelio Bernal Andreo (Deep Sky Colors)
(via APOD: 2012 January 29 - Molecular Cloud Barnard 68)
That is not an imaging error that you are seeing. There really is a “hole in the sky”. Well, OK, it’s a really dark, relatively close (500 light-years) molecular cloud that obscures the background stars rather well. Barnard 68 is a very dark absorption nebula. Because it is so close, it effectively eliminates a region from the night sky, blocking the stars behind it.
But Barnard 68 is changing, and, relatively soon in astronomical time-frames, it will become a whole different kind of nebula.
Dark nebula are formed from gas and dust, in this case a lot of dust and a molecular cloud. The gravity inside a molecular cloud can cause slightly denser regions to go through a period of sudden material increase as they accrete more matter to themselves. As this goes on, the area becomes a proto-star, then a star. The ESO’s VLT has captured evidence of this happening in Barnard 68 in the infrared (IR is really good a going through dust clouds).
(ESO’s Very Large Telescope captures the Barnard 68 cloud in a variety of infrared wavelengths and combines the data to create this image of early star formation.)
In any case, don’t worry too much about a hole in the sky. It’s just gas and dust…and will be new stars someday.
Image Credit: FORS Team, 8.2-meter VLT Antu, ESO
(via APOD: 2012 January 11 - Little Planet Lovejoy)
Take a 360-degree panoramic from the southern hemisphere. Make sure you get one of the last views of Comet Lovejoy in the sky. Piece it back together in a spherical projection. Voila, a Little Prince-esque view of Earth surrounded by the cosmos. Click through for the roll-over as it points out Lovejoy, the Magellanic clouds (satellite galaxies to the Milky Way) and the Coalsack dark nebula.
