Hub of beauty

Hub of beauty

Hub of beauty

Bad Astronomy
The entire universe in blog form
Nov. 10 2009 11:03 AM

Hub of beauty


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!

Phil Plait Phil Plait




[Oh yes, you want to click to embiggen that-- what I show here is a very compressed version. Or you can go here for a massive copy. You can also get wallpaper versions here.]

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.

hst_spitzer_chandra_mw2There 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.



You might want to look at an annotated version of this image so you can get your bearings. It's worth it!




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.


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.
