Oh, this is good.  I couldn’t resist putting this up today.  What an image!

NASA image of W340.

Here’s what NASA had to say about this amazing image (don’t forget to enlarge — it’s amazing):

VV 340, also known as Arp 302, provides a textbook example of colliding galaxies seen in the early stages of their interaction. The edge-on galaxy near the top of the image is VV 340 North and the face-on galaxy at the bottom of the image is VV 340 South. Millions of years later these two spirals will merge — much like the Milky Way and Andromeda will likely do billions of years from now. Data from NASA’s Chandra X-ray Observatory (purple) are shown here along with optical data from the Hubble Space Telescope (red, green, blue). VV 340 is located about 450 million light years from Earth.

Because it is bright in infrared light, VV 340 is classified as a Luminous Infrared Galaxy (LIRG). These observations are part of the Great Observatories All-Sky LIRG Survey (GOALS) combining data from Chandra, Hubble, NASA’s Spitzer Space Telescope and Galaxy Evolution Explorer (GALEX) and ground-based telescopes. The survey includes over two hundred LIRGs in the local Universe. A chief motivation of this study is to understand why LIRGs emit so much infrared radiation. These galaxies generate energy at a rate this is tens to hundreds of times larger than that emitted by a typical galaxy. An actively growing supermassive black hole or an intense burst of star formation is often invoked as the most likely source of the energy.

Work on the full GOALS survey is ongoing, but preliminary analysis of data for VV 340 provides a good demonstration of the power of observing with multiple observatories. The Chandra data show that the center of VV 340 North likely contains a rapidly growing supermassive black hole that is heavily obscured by dust and gas. The infared emission of the galaxy pair, as observed by Spitzer, is dominated by VV 340 North, and also provides evidence for a growing supermassive black hole. However, only a small fraction of the infrared emission is generated by this black hole.

By contrast most of the ultraviolet and short wavelength optical emission in the galaxy pair — as observed by GALEX and HST — comes from VV 340 South. This shows that VV 340 South contains a much higher level of star formation. (The Spitzer and GALEX images are not shown here because they strongly overlap with the optical and X-ray images, but they are shown in a separate composite image.) VV 340 appears to be an excellent example of a pair of interacting galaxies evolving at different rates.

These results on VV 340 were published in the June 2009 issue of the Publications of the Astronomical Society of the Pacific. The lead author was Lee Armus from the Spitzer Science Center in Pasadena, CA.

Image credit: X-ray NASA/CXC/IfA/D.Sanders et al; Optical NASA/STScI/NRAO/A.Evans et al

NGC 3521 in the constellation Leo from the ESO. Click for larger. Credit: ESO/O. Maliy

I decided to post this lovely image by the ESO thinking (apparently not too hard) this would be something to look for while watching the Perseid meteor shower.  The galaxy is about a magnitude 8.9, but perhaps with a nice dark sky with a lot of clarity I might be able to see it with binoculars and I could always use the scopes.

Then I remembered seeing and making a mental note of the moon rise about a week ago as I was playing with Holly (my getting large puppy) and realized there would be a full moon.  This will wash out the meteor shower some, still the moon is low in the sky and the Perseids are a fantastic shower so I’ll still be out there IF I have somewhat decent skies.

What about NGC 3521?  That’s the other part things not working out.  For one thing the galaxy is located 35 million light-years away in the constellation of Leo, specifically at:

RA 11h 06m 25s
Dec -00^o02’13″

and will be out of a viewing position for me by the time it’s dark enough to see it.  Oh well the image is incredible and way more detailed than any I’d get; I won’t say totally better than I would get because seeing it for myself is always more satisfying.

The caption below refers to Messier’s Catalog here’s the online version at SEDS.

Here’s the ESO caption for the image (you can larger versions at this link too):

This new picture from ESO’s Very Large Telescope shows NGC 3521, a spiral galaxy located about 35 million light-years away in the constellation of Leo (The Lion). Spanning about 50,000 light-years, this spectacular object has a bright and compact nucleus, surrounded by richly detailed spiral structure.

The most distinctive features of the bright galaxy NGC 3521 are its long spiral arms that are dotted with star-forming regions and interspersed with veins of dust. The arms are rather irregular and patchy, making NGC 3521 a typical example of a flocculent spiral galaxy. These galaxies have “fluffy” spiral arms that contrast with the sweeping arms of grand-design spirals such as the famous Whirlpool Galaxy, or M51, discovered by Charles Messier.

NGC 3521 is bright and relatively close-by, and can easily be seen with a small telescope such as the one used by Messier to catalogue a series of hazy and comet-like objects in the 1700s. Strangely, the French astronomer seems to have missed this flocculent spiral even though he identified several other galaxies of similar brightness in the constellation of Leo.

It was only in the year that Messier published the final version of his catalogue, 1784, that another famous astronomer, William Herschel, discovered NGC 3521 early on in his more detailed surveys of the northern skies. Through his larger, 47-cm aperture, telescope, Herschel saw a “bright center surrounded by nebulosity,” according to his observation notes.

In this new VLT picture, colorful, yet ill defined, spiral arms replace Herschel’s “nebulosity”. Older stars dominate the reddish area in the center while young, hot blue stars permeate the arms further away from the core.

Oleg Maliy, who participated ESO’s Hidden Treasures 2010 competition [1], selected the data from the FORS1 instrument on ESO’s VLT at the Paranal Observatory in Chile that were used to create this dramatic image. Exposures taken through three different filters that passed blue light (colored blue), yellow/green light (colored green), and near-infrared light (colored red) have been combined to make this picture. The total exposure times were 300 seconds per filter. Oleg’s image of NGC 3521 was a highly ranked entry in the competition, which attracted almost 100 entries.