Archives for May 2021

Telescope: ES Comet Hunter MN6 at f/4.8, Orion Atlas EQ-G

Camera: Baader modified Nikon 610

Filter: 2” Orion Imaging Skyglow Filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 18x120sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/50sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency

Lensed Sky Quality Meter: 18.4 mag/arc-sec^2

Stacking: Mean with a 2-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard Nikon, Nebulosity, Deep Sky Stacker, Photoshop

To the upper right is NGC 4631 (The Whale) a large edge-on spiral galaxy with the much smaller dwarf elliptical galaxy NGC 4627 (The Pup) just to its north. These two galaxies form an interacting pair with the smaller galaxy distorting the disk of the larger, forming its distinctive shape. To the lower left is another distorted edge-on spiral galaxy, NGC 4656, nicknamed the Hockey Stick. Just off of the tip of the hook is an edge-on spiral far off in the background.

NGC 4631 & 4656 are currently well places high in the northeast early in the evening.

Telescope: ES Comet Hunter MN6 at f/4.8, Orion Atlas EQ-G

Camera: Baader modified Nikon 610

Filter: 2” Orion Imaging Skyglow Filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 36x60sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/50sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency

Lensed Sky Quality Meter: 18.4 mag/arc-sec^2

Stacking: Mean with a 2-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard Nikon, Nebulosity, Deep Sky Stacker, Photoshop

M92 is the ‘other’ globular cluster in Hercules. M92 lies to the northeast of the popular M13 globular cluster in a relatively lonely patch of sky making it a bit harder to locate, but well worth the effort. Interestingly, M92 is listed as being fainter than M13 (Mv 6.4 for M92 vs. 5.8 for M13), but I find the core of M92 to be a tad brighter than M13. This is likely the result the apparent size of M13 being larger than M92 giving M13 a higher total integrated brightness.

M92 currently rises in the northeast late in the evening and is high overhead at dawn.

Telescope: Meade 12” LX850 ACF @ f/8, Orion Atlas EQ-G

Camera: Baader modified Nikon 610

Filter: High Point 2” IR Blocking Filter

Guide scope: Astro-Tech 60mm, ASI290MM Mini, PHD2

Exposure: 11x120sec, ISO 200, saved as FITS

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/2sec, Tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency, haze

Lensed Sky Quality Meter: 18.3 mag/arc-sec^2

Stacking: Mean with a 2-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard Nikon, Deep Sky Stacker, Photoshop

At the center of this image is four galaxies that comprise the Hickson 44 Compact Galaxy Group located just north of the beautiful binary star Algieba in Leo. From left to right these NGC 3193, NGC 3190, NGC 3187, and NGC 8185. Of these NGC 3193 is an elliptical and the others are spirals. NGC 3187 is a barred spiral with a highly warped disk. Paul Hickson cataloged 100 compact galaxy groups, most of which form interacting groups with local concentrations of dark matter.

The Hickson 44 compact galaxy group is currently well placed high in the east as the sky darkens. (Photo credit; John Graham, 3/29/2021)