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The North American Nebula

Pardon the late afternoon post, I’m rocking some kind of stomach flu today. What an interesting day – this morning, not even water could take residence in my stomach.  I tried, but the water said “I’M OUT!”

Light from the universe is pretty cool.  There is a large nebula that has a quaint resemblance to the North American continent (which is funny enough called The North American Nebula) that is sometimes visible on really dark nights.  What makes this nebula cool is that as you filter out certain wavelengths of light (like the IR spectrum or UHC filters), our perception of the light from the nebula changes.  The shape really kind of goes away altogether, but who cares – that mass of points and bands of light and color is absolutely amazing.

Check out this image – it’s a quad image from wikipedia of the North American Nebula, but with filters in place for each image:

(You have got to see this one full size.  Seriously.)

This is an amazing thing – I know that there are some serious nerds who read JimOnLight.com, hopefully you all read the NASA Image of the Day gallery, this was the post from yesterday:

From the NASA Image of the Day post from October 18:

This swirling landscape of stars is known as the North America Nebula. In visible light, the region resembles North America, but in this image infrared view from NASA’s Spitzer Space Telescope, the continent disappears.

Where did the continent go? The reason you don’t see it in Spitzer’s view has to do, in part, with the fact that infrared light can penetrate dust whereas visible light cannot. Dusty, dark clouds in the visible image become transparent in Spitzer’s view. In addition, Spitzer’s infrared detectors pick up the glow of dusty cocoons enveloping baby stars.

Clusters of young stars (about one million years old) can be found throughout the image. Some areas of this nebula are still very thick with dust and appear dark even in Spitzer’s view. 

The Spitzer image contains data from both its infrared array camera and multi-band imaging photometer. Light with a wavelength of 3.6 microns has been color-coded blue; 4.5-micron light is blue-green; 5.8-micron and 8.0-micron light are green; and 24-micron light is red. This image is from February 2011.

This is totally worth a few minutes, check out this video – it breaks down the nebula with visible and invisible light filters and details. Unbelievably beautiful.

What A Fun… Unusual Cosmic Blast!

Have you seen the news stories about this “unexplained cosmic blast” that NASA’s Swift Satellite captured a few weeks ago?  NASA scientists have been checking out this crazy monstrous gamma ray explosion they observed back in March, but that continues to keep shining.  Typically these types of cosmic explosions go on for about an hour or so, maybe a little longer, but this one was huge and bright, with very high levels of radiation being emitted from the site.

Well, research is ongoing into this crazy little phenomena, but the general feeling towards this bright burst is that a star in another galaxy has gotten too close to its central black hole, and the black hole tore the star to smithereens – cosmic smithereens, that is.  I wonder if that’s the name of the new band by Jack Black and Judd Apatow.

When a star gets torn apart by a black hole like we think this one has, observers will notice a stream of radiation, light, and particles that makes a pretty good light show for a few hours.  This one has been going on for a few weeks, which is a bit puzzling, but scientists are thinking that we’re looking directly into the stream of light and particles that the star is giving off.  When a star is torn apart like this, a stream of light will be created along the star’s rotational axis – essentially we’re looking into a big bright stream of star destruction.  This is crazy pretty, no?

From an article at NASA’s Swift Satellite website:

That same day, astronomers used NASA’s Chandra X-ray Observatory to make a four-hour-long exposure of the puzzling source. The image, which locates the object 10 times more precisely than Swift can, shows that it lies at the center of the galaxy Hubble imaged.

“We know of objects in our own galaxy that can produce repeated bursts, but they are thousands to millions of times less powerful than the bursts we are seeing now. This is truly extraordinary,” said Andrew Fruchter at the Space Telescope Science Institute in Baltimore.

“We have been eagerly awaiting the Hubble observation,” said Neil Gehrels, the lead scientist for Swift at NASA’s Goddard Space Flight Center in Greenbelt, Md. “The fact that the explosion occurred in the center of a galaxy tells us it is most likely associated with a massive black hole. This solves a key question about the mysterious event.”

Most galaxies, including our own, contain central black holes with millions of times the sun’s mass; those in the largest galaxies can be a thousand times larger. The disrupted star probably succumbed to a black hole less massive than the Milky Way’s, which has a mass four million times that of our sun

Astronomers previously have detected stars disrupted by supermassive black holes, but none have shown the X-ray brightness and variability seen in GRB 110328A. The source has repeatedly flared. Since April 3, for example, it has brightened by more than five times.

Scientists think that the X-rays may be coming from matter moving near the speed of light in a particle jet that forms as the star’s gas falls toward the black hole.

“The best explanation at the moment is that we happen to be looking down the barrel of this jet,” said Andrew Levan at the University of Warwick in the United Kingdom, who led the Chandra observations. “When we look straight down these jets, a brightness boost lets us view details we might otherwise miss.”

This brightness increase, which is called relativistic beaming, occurs when matter moving close to the speed of light is viewed nearly head on.

I’m gonna hold off on stocking up for the end of the world another few weeks.  :)