January 19, 2025

NGC 7293 – The Helix Nebula is Aquarius

NGC 7293 – The Helix Nebula is Aquarius

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

Camera: Baader modified Nikon D610

Filter: 2” Radian Triad Ultra Hb, OIII, Ha, SII filter

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

Exposure: 23x180sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/5sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, poor transparency

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

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

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

The Helix is one of the closest planetary nebula with a distance of only 650 light years. It spans a diameter of about 2.5 light years and is relatively young with an age estimated to be about 10,600 years. NGC 7293 is one of those wonderful objects that hides in plain sight. It is so large (about half the size of the full moon) that its light is spread out over a large area, making it very difficult to see and all but invisible from my red-zone backyard.

NGC 7293 is currently in the southwest as the sky darkens.

M27 – Planetary Nebula in Vulpecula

M27 – Planetary Nebula in Vulpecula

Telescope: Light Switch 8 @ f/6.2 (Optec 0.62x focal reducer), altaz mode

Camera: Full Spectrum Modified Canon 600D, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 37x10sec, ISO 1600, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/10sec, Tee shirt flats taken at dusk

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

Lensed Sky Quality Meter: 18.6

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

M27, the Dumbbell nebula, is an expanding shell of gas that was ejected from a sun-like star as it exhausted its hydrogen fuel. Swollen into a red giant, the star shed its outer shell while its core collapsed into a white dwarf. Fierce UV radiation from the collapsed core sets the surrounds gas aglow with the blue/green light of doubly ionized oxygen. The diameter of the nebula is about 1 light-year with an estimated age of 9,800 years. Located between Sagitta and Cygnus, M27 is fairly easy to find with a small telescope. Visually, it shows two lobes connected by a neck of nebulosity, giving the nebula its characteristic dumbbell shape.

This is the last image in a very long series of 42 images taken to explore basic deepsky imaging using fairly simple equipment including a stock and a modified DSLR and several different 8” SCTs operating at f/10 and f/6.3, all on various altaz mounts (LX90, LX65, and Light Switch), and just an interval timer, no computer, no guiding. This has been a really fun journey and one that I’ll likely pick up again in the spring. It has also proven to be very helpful reminding me just how much you can do with relatively gear and it offers a nice option for a variety of different bright targets and projects such as monitoring asteroids and variable stars.

So much to try, so few clear nights…

NGC 188 – Open Cluster in Cepheus

NGC 188 – Open Cluster in Cepheus

Telescope: Light Switch 8 @ f/6.2 (Optec 0.62x focal reducer), altaz mode

Camera: Full Spectrum Modified Canon 600D, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 40x10sec, ISO 1600, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/10sec, Tee shirt flats taken at dusk

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

Lensed Sky Quality Meter: 18.4

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

Located less than 5 degrees from the north celestial pole NGC 188 is one of the most northern objects in the New General Catalog. It is also one of the oldest open clusters known with an estimated age on the order of 5 billion years. Open clusters usually slowly disperse as they interact with other stars in the surrounding galaxy. NGC 188, however, lies above the galactic plane where it is fairly isolated. Composed almost entirely of 12 and 13th magnitude yellow giants, I find this cluster to be quite delicate, requiring very good transparency to be visible in an 8” telescope. Under these conditions it blossoms into a rich field of tiny pinpoints of light on the edge of visibility and it is quite beautiful. In a larger telescope it becomes easier to see, but remains quite faint and subtle.

NGC 188 is currently well placed above Polaris in the evening sky.

NGC 7789 – Open Cluster in Cassiopeia

NGC 7789 – Open Cluster in Cassiopeia

Telescope: Light Switch 8 @ f/6.2 (Optec 0.62x focal reducer), altaz mode

Camera: Full Spectrum Modified Canon 600D, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 40x10sec, ISO 1600, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/10sec, Tee shirt flats taken at dusk

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

Lensed Sky Quality Meter: 18.5

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

NGC 7789 is a large and wonderfully rich open cluster located just west of Cassiopeia. It was discovered by Caroline Herschel in 1782 and is sometimes called Caroline’s Rose. It is a delicate object in small to moderate scopes, but blossoms into a rich field in large telescopes. When viewing this cluster I like to spend some time with the field. At first all I will see are the foreground stars and perhaps a soft glow in the background. As my eye adjusts, the first faint stars appear, and then it slowly blooms into a beautiful patch of stardust.

NGC 7789 is currently high in the northeast after sunset.

M52 – Open Cluster in Cassiopeia

M52 – Open Cluster in Cassiopeia

Telescope: Light Switch 8 @ f/6.2 (Optec 0.62x focal reducer), altaz mode

Camera: Full Spectrum Modified Canon 600D, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 22x10sec, ISO 1600, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/10sec, Tee shirt flats taken at dusk

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

Lensed Sky Quality Meter: 18.5

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

M52 is a relatively bright open cluster just to the west of Cassiopeia. Visually, M52 appears as a fine patch of stardust in small telescopes while larger telescopes show a broad expanse of fainter stars. The faint, rich field to the right of M52 is the open cluster Czernik 43.

M52 is currently high in the northeast after sunset

M81 & 82 – Spiral Galaxies in Ursa Major

M81 & 82 – Spiral Galaxies in Ursa Major

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

Camera: Baader modified Nikon D610

Filter: Orion Imaging Skyglow Filter

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

Exposure: 82x60sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/250sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, poor transparency

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

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

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

This is M81 (bottom) and M82 (top), two bright spiral galaxies lying about 12 million light years away in Ursa Major. At present, these two galaxies are about 150,000 light years apart, though a few hundred million years ago the two passed very close to each other. The dark dust lane slashing across M82 is one result of this close encounter with M81 as are the blue star formation regions in M81. To the lower left is NGC 3077, another spiral galaxy. Visually, M81 and 82 are fairly easy to see with a modest telescope even from my light polluted backyard. M81 shows its beautiful soft core similar to M31 while M82 shows its elongated shape interrupted by the dust lanes giving it a very irregular shape.

M81 and M82 is currently rising in the northeast as the sky darkens and is high overhead at dawn.

M42/43 and The Sword of Orion

M42/43 and The Sword of Orion

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

Camera: Baader modified Nikon D610

Filter: Orion Imaging Skyglow Filter

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

Exposure: 122x30sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/250sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, poor transparency

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

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

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

I like how this field shows how the Great Nebula is bracketed by NGC 1977 to the north and NGC 1980 to the south. Forming the Sword of Orion, this is a wonderful region to explore with a small telescope. Although visually the nebula shows a soft gray, it includes a wealth of fine detail. This is also a very rewarding region to photograph and even short exposures can show the beautiful range of colors. The red of the Great Nebula is the emission of hydrogen gas set aglow by hot young stars within the nebula, while the smoky gray/blue of M42 and the beautiful soft blue of NGC 1977 is starlight reflecting off of interstellar dust while the dark lanes are veils of dust in the foreground.

The Sword of Orion is currently well placed rising in the east as the sky darkens. (Photo credit; John Graham, 11/4/2021)

NGC 457 – The Owl Cluster in Cassiopeia

NGC 457 – The Owl Cluster in Cassiopeia

Telescope: Light Switch 8 @ f/6.2 (Optec 0.62x focal reducer), altaz mode

Camera: Full Spectrum Modified Canon 600D, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 39x10sec, ISO 1600, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/10sec, Tee shirt flats taken at dusk

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

Lensed Sky Quality Meter: 18.6

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

NGC 457 is one of my favorite open clusters in just about any size telescope. It makes a fine target for binoculars and small telescopes and becomes a very rich field in larger scopes. The two bright distinctive foreground stars makes it fairly easy to locate. In a small telescope it is worth taking some time with this field. At first your eye may only see the two bright foreground stars and a few of the brighter stars of the cluster. As your eyes relax you may start to see some of the fainter background stars and the cluster will begin to blossom into a beautiful field of stardust.

NGC457 is currently well placed high in the northeast after sunset.

M2 – Globular Cluster in Aquarius

M2 – Globular Cluster in Aquarius

Telescope: Light Switch 8 @ f/6.2 (Optec 0.62x focal reducer), altaz mode

Camera: Full Spectrum Modified Canon 600D, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 38x10sec, ISO 1600, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/10sec, Tee shirt flats taken at dusk

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

Lensed Sky Quality Meter: 18.6

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

M2 is a big, beautiful globular cluster that is well placed in the eastern sky in late summer and early fall. It is an easy target for a small telescope. Under dark skies it can even be glimpsed without a telescope or even binoculars. M2 is about 37,500 light years away and lies beyond the galactic center. Like most globular clusters M2 is an ancient relic of the early universe with an estimated age of about 13 billion years.

M2 is currently in high the southwest at sunset.

M31, 32, & 110 – Galaxy Group in Andromeda

M31, 32, & 110 – Galaxy Group in Andromeda

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

Camera: Baader modified Nikon D610

Filter: Orion Imaging Skyglow Filter

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

Exposure: (100 + 84)x120sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×3sec, LED Tracing Tablet covered with 3 layers of muslin

Average Light Pollution: Red zone, poor transparency

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

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

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

M31 is an iconic spiral in the constellation of Andromeda. Under dark skies it is easily visible to the naked eye and from urban skies it is an easy object for binoculars and small telescopes. At a distance of some 2 million light years, it is the farthest object visible to the naked eye. M31 also has several satellite galaxies, two of which are visible here. M32 is about as bright as the core of M31 and is located at the bottom center of this field. To the upper right is the much fainter M110. It is easy to be disappointed with the visual appearance of M31 since it is often shown in highly processed images such as the one I give here. However, the true appearance is quite beautiful in its own way. The core is relatively bright and almost stellar, surrounded by a soft luminous glow that I always think of as pearl.

I have always found that imaging the M31 group from my backyard and the associated processing to be surprisingly challenging due to its large size and the faint outer arms that tend to fade into my sky-glow. For this image I combined source images taken over two consecutive evenings. Unfortunately, the transparency on both evenings were relatively poor, but I’m happy with the result. This also does a good job showing the wide, flat field of the MN6 when used with a full frame camera.

M31 is currently well place high in the east at sunset.