NGC 7331 (Caldwell 30)

Telescope: Planewave 17" CDK reflector, 1940 mm FL
Camera: FLI-PL6303E, 3072 x 2048 pixels
Exposure: L:9x3m R:3x3m G:3x3m B:3x3m, HA:1x10m (ngc7331_HA_dr4.fits) from the Kitt Peak National Observatory 2.1-meter telescope to highlight the H-II regions in red. Stacked, aligned and processed with PixInsight.
Location: Mayhill, New Mexico (Elevation 7380')
Image Center (J2000): RA 22h 37m 02s, Dec 34° 25' 04"

Spiral galaxy in Pegasus, apparent size 10' x 3', mag 10.35. Spiral arms spin outward from a central bulge and can be traced almost to the nucleus. Blue spiral arms indicate star forming activity. The western half of the galaxy is outlined with a dark outer dust lane. One of the brighter galaxies not included in Charles Messier's list. Brightest Cepheid variables are about mag 25, too dim for this image. The smaller galaxies (NGC 7335, NGC 7337 and NGC 7340) in close alignment with NGC 7331 has occured by chance, they are all about 10 times more distant.
Raw data for this image can be downloaded.


NGC 7331 (Caldwell 30), Spiral galaxy in Pegasus, apparent size 10' x 3', mag 10.35. Spiral arms spin outward from a central bulge and can be traced almost to the nucleus. Blue spiral arms indicate star forming activity. The western half of the galaxy is outlined with a dark outer dust lane. One of the brighter galaxies not included in Charles Messier's list. Brightest Cepheid variables are about mag 25, too dim for this image. The smaller galaxies (NGC 7335, NGC 7337 and NGC 7340) in close alignment with NGC 7331 has occured by chance, they are all about 10 times more distant., acquired with a remote telescope at Mayhill, New Mexico (Elevation 7380')

Object Label Identifier Notes
Galaxy G2 2MASX J22365123+3423047 Galaxy, unclassified type
Galaxy NGC 7331B NGC 7331B Dwarf Galaxy Candidate, identified in 2012
Galaxy NGC 7335 NGC 7335 Galaxy
Galaxy NGC 7336 NGC 7336 Galaxy, 0.4' x 0.3', mB=15.0
Galaxy NGC 7337 NGC 7337 Galaxy, 1' x 1', mB=15.2, spiral
HII Region HII Regions HII Regions 11 are marked.
Star NGC 7333 NGC 7333 Error in NGC catalog, a 15th-magnitude star.

Click on the image to display the plate solved image with annotations. 3' across NGC 7331 is about 39,000 light years.


FITS files to create this image:

Luminance:

NGC 7331 Luminance

Image shown is Luminance 001.fits. Each file is 180 seconds, Planewave 17" reflector, 3072x2048 pixels, unbinned with Darks, Bias and Flats applied. Data acquired Aug 2, 2016.


Luminance 001.fits
Luminance 002.fits
Luminance 003.fits
Luminance 004.fits
Luminance 005.fits
Luminance 006.fits
Luminance 007.fits
Luminance 008.fits
Luminance 009.fits

Red:

NGC 7331 Red

Image shown is Red 001.fits. Each file is 180 seconds, Planewave 17" reflector, 3072x2048 pixels, binned 2x with Darks, Bias and Flats applied. Data acquired Oct 1, 2016.


Red 001.fits
Red 002.fits
Red 003.fits

Green:

NGC 7331 Green

Image shown is Green 001.fits. Each file is 180 seconds, Planewave 17" reflector, 3072x2048 pixels, binned 2x with Darks, Bias and Flats applied. Data acquired Oct 1, 2016.


Green 001.fits
Green 002.fits
Green 003.fits

Blue:

NGC 7331 Blue

Image shown is Blue 001.fits. Each file is 180 seconds, Planewave 17" reflector, 3072x2048 pixels, binned 2x with Darks, Bias and Flats applied. Data acquired Oct 1, 2016.


Blue 001.fits
Blue 002.fits
Blue 003.fits

HA:

NGC 7331 HA

Image shown is HA 001.fits. 600 seconds, Kitt Peak 2.1 meter, 3238x2019 pixels, stacked and flat fielded. Image taken Nov 15, 2001 as part of the Spitzer Infrared Nearby Galaxies Survey.


HA 001.fits


Files can be loaded into PixInsight directly from the PixInsight console. For example, in the PixInsight console enter:
    open "http://www.remote-astrophotography.com/NGC7331/NGC 7331-HA-001.fits"


NGC 7331 in Infrared


Processed from SPITZER Space Telescope data using PixInsight, IRAC Channel 1 (3.6 µm), ngc7331_v7.phot.1.fits, 1460x1860 pixels, 1500 second exposure, non-visible IR wavelength mapped to red, dynamic range reduced to increase core detail, contrast enhanced. Image data acquired Mar 30, 2007.


NGC 7337

NGC 7337

There are few high resolution images of this lopsided 15th mag barred spiral galaxy, about 5' SE from NGC 7331 and about 1' in diameter. The sharply brighter core is visible along with spiral arms apparently only on one side. An unrelated 15th magnitude star lies in front of the galaxy.