Messier 51 ~ The Great Whirlpool Galaxy
Optics: |
Ritchey–Chrétien 20" F/8.2 (4166mm FL) |
Processing: |
PixInsight, Photoshop |
Camera: |
SBIG STXL-11000 with Adaptive Optics |
Date: |
May-June, 2020 |
|
11 Megapixel (4008 x 2672 16-bit sensor) |
Location: |
Columbus, Texas |
Exposure: |
LRGB = 480:100:60:100 minutes |
Imager: |
Kent E. Biggs |
Probably the best
known, most often observed galaxy in the northern hemisphere,
the Whirlpool Galaxy is one of the brightest and most beautiful
of spiral galaxies. Also known as M51, it is another example of
colliding galaxies where the larger galaxy on the left, NGC
5194, may absorb the smaller right side galaxy, NGC 5195,
annotated by hovering over the image. While these two massive
galaxies may be passing each other and just shaking hands, most
likely NGC 5195 has passed through the galactic plane multiple
times, caused increased star formation along the arms, and is
currently lies behind the larger galaxy NGC 5195.. 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 visible over the bue spiral star arms. The red color indicate
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
so far away thay apear as faint cloudy puffs of smoke. Note
also visible are two visually smaller galaxies IC 4277 and IC
4278.
Two very exciting phenomena are also visible in this
image. First, is the detection of a very distant
quasars at 11.1 billion light years away, meaning it’s light
left it when the universe was only 2-3 billion years old; today
the universe is about 13.7 billion years old (see annotation by
hovering over the image). 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 large 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.
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 by hovering over the image. 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.
Below is the same image, same data with my previous pre- and post-
processing workflow. Hovering over the below image shows a direct comparison
to the current processing workflow using PixInsight software for the
majority of stacking and sharping, 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.
The stats for M51 are Constellation: Canes Venatici, RA: 13h 29m
53.3s, Dec: +47° 11' 48, Magnitude: 9.0 (B), Size: 10.3'x8.1',
Class: SA(s)bc pec.