Details: . The M51 pair of galaxies is about 30 million light years away, therefore with a visual diameter of about 10 minutes of arc (1/6 of a degree), simple trigonometry calculates a size of about 75 thousand light years or about 70% the size of our Milky Way galaxy. Its mass is only about 10% of our galaxy at about 150 million suns, compared to the 1.5 trillion suns of our galaxy. While these two massive galaxies may be passing each other and just shaking hands, most likely NGC 5195 has passed through the galactic plane of NGC 5194 multiple times, caused increased star formation along the arms, and currently lies behind the larger galaxy. Even through small telescopes the pair of galaxies is visible; through a 6-8" telescope you can start to resolve the wonderful galaxy arms. Note how the arms of NGC 5194 are slightly bent, likely due to the gravitational distortion of NGC 5195.

M51 is also a Seyfert galaxy, which accounts for about 10% of all galaxies. Seyferts have very active central cores powered similarly to those of quasars, but much closer by and less luminous. We now know that supermassive black holes surrounded by accretion disks of doomed material dominate the centers of these galaxies. Visible on the left side of NGC 5194 is a group of red colored emission nebula, contrasted over the blue spiral star arms. The red color indicates gas and dust being excited by nearby stars. The blue color shows areas of active star formation, where young hot stars glow blue-white. Finally the ghostly white areas around the galaxy are 100s of millions of stars, like our sun, so far away that they appear as faint cloudy puffs of smoke.

Annotations. In the image above, hover a mouse or curser over the image to show annotations of the galaxy with several enlarged insets identifying interesting features! Beginning at the top, 12 o’clock position, clearly visible are two visually smaller galaxies IC 4278 and IC 4279 in the Index Catalogue, or IC Catalogue, the first major update to the NGC Catalogue mentioned above. Continuing clockwise, next are two very exciting phenomena.

First, is the detection of a very distant quasar at 11.1 billion light years away, meaning it’s light left it when the universe was only 2-3 billion years old and way before our earth and sun even existed!. Today the universe is about 13.7 billion years old. Quasar is short for quasi-stellar object or QSO. They are extremely bright active galaxies powered by supermassive black holes of tens of billions of solar masses. This means 10,000,000,000 suns have been squeezed into an infinitesimally small point. Their brightness can exceed thousands of times the brightness of our whole Milky Way galaxy of 200 billion suns. Because they are so far away, they are likely the cores of very young, very active galaxies and since our universe is expanding faster the further an object is away from us, they have highly red shifted spectrums. This Quasar, designated J133004.71+472301.0 is a galaxy with a redshift near 3.0, meaning it is moving away from us at nearly 90% the speed of light, is 11 billion years old, and was 11 billion light years away at the time its light left it. Today however it is nearly 18 billion light years away from us and therefore outside of our visible universe. Light leaving it today will never reach us.

Continuing clockwise in the above image, a second exciting phenomena is an apparent jet of blue material that can be seen just to the right of the core of NGC 5195 as annotated. This is likely a jet of newly formed stars being disrupted, perhaps even expelled into intergalactic space by the merging galaxies. There are trillions of stars in intergalactic space not associated with a parent galaxy. Civilizations inhabiting these star systems would never know the beauty of the Milky Way like we do. Continuing clockwise are insets showing the neculei of both NGC 5195 and NGC 5195, as well as nebulae within the M51 galaxy. Some of these nebulae may be as large and bright as our own Orion Nebula, and someday space telescopes may resolve as much detail.

Below Images: In the first image below, the same image has been processed to remove all foreground stars as these stars are all within our own Galaxy. This is what the view would appear like if no stars existed along our line of sight and what we would see outside of our own galaxy. Using a mouse to hover over the image, brings all the stars back. The second image below shows an enlarged and cropped version of M51 and this time hovering a mouse makes the stars disappear. Finally, the third image below is the same image, same data with my previous pre- and post- processing workflow. Hovering over the third below image shows a direct comparison to the current processing workflow using PixInsight software for the majority of stacking and sharpening, with Photoshop use for final touch-up. Note the improved color throughout the image from object to stars, as well as the visibilty and more natural look of very faint stars and object details.

Object Statistics: Constellation: Canes Venatici, Right Ascension: 13h 29m 53.3s, Declination: +47° 11' 48, Magnitude: 9.0 (B), Size: 10.3'x8.1', Class: SA(s)bc pec.