NGC 55 – 200+ Hours

This image of NGC 55 represents one of my favorite galaxies, captured using three different telescopes and four different cameras, over 3 years with a cumulative exposure time of 223 hours. The data was contributed by several collaborators, enabling the creation of my first comprehensive SHOLRGB galaxy image, aside from previous work on the Large and Small Magellanic Clouds, which involved 16 panes each and moderately less exposure per pane.

The image was processed using the SHO palette—assigning S to Red, H to Green, and O to Blue—with additional RGB stars and luminance data integrated. The result reveals extensive detail for a galaxy located approximately 6.5 million light years away. For context, the Small and Large Magellanic Clouds are situated between 160,000 and 200,000 light years from Earth. Comparable imaging efforts I have seen include M33, which is roughly 2.7 million light years distant, similar to the Andromeda Galaxy as well as NGC 300.

NGC 55, also known as The Whale Galaxy and designated Caldwell 72, is a barred irregular spiral galaxy in the constellation Sculptor. Due to its nearly edge-on orientation, the galaxy appears asymmetrical, resembling a cigar. Its bulge is diffuse, broad, and slightly elongated. Notably, this image highlights a prominent hydrogen outflow emanating from the galaxy's core. With numerous clouds of gas and dust, NGC 55 exhibits highly active star-forming regions characterized by pink hues, as well as young blue star clusters.

 Interspersed among these stellar populations are over one hundred Cepheid variable stars that undergo periodic changes in brightness. This characteristic makes them valuable as cosmic distance indicators, extending up to several tens of millions of light-years due to their consistent relationship between luminosity and period.

 Together with NGC 300, NGC 55 belongs to the Local Group of Galaxies, which also includes the Andromeda Galaxy (M31), the Large and Small Magellanic Clouds, and approximately forty other members.

 It is probable that NGC 55 and its neighboring galaxy NGC 300 orbit each other, forming a gravitationally bound pair.

Taken from SWOS in El Sauce, Chile

Equipment and exposure times:

24” PlaneWave CDK (Sbig 16803) SWOS Group (LRGBHA) 8 - 5 – 5 - 5 - 10 Hours

Total 43 Hours

24” PlaneWave CDK (Moravian C5) SWOS Group (LRGBHaO3S2) 13 – 4 – 4 – 4 – 28 – 28 - 20 Hours

Total 101 Hours

24” PlaneWave CDK (QHY600M) From Matt Dietrich, (Red Ha O3) 4 - 25 - 25 Hours

Total 54 Hours

1 Meter ASA RC-1000 (Chilescope T1) (FLI PL 16803) From Alaxander Zaytsev (LRGBHaO3S2) 2 - 2 -1.5 - 2 - 7 - 5.5 - 5.5 - 5.5 - 5.5 Hours

Total 25 Hours

Grand Total Hours: 223 Hours

Image Processing: Mark Hanson

Image Data: Hanson, Dietrich, Zaytsev, Mazlin, Parker, Forman, Magill

Enjoy,

Dietrich, Zaytsev and the SWOS Group

NGC 55 – The Whale Galaxy

New Updated Image: This is a new version with the help of Matt Dietrich wonderful Ha data 28hours, thanks Matt. This really made this galaxy pop.

NGC 55, also occasionally referred to as The Whale Galaxy and Caldwell 72, is a barred irregular spiral galaxy located about five million light years away in the constellation Sculptor. Along with its neighbor NGC 300, it is one of the closest galaxies to the Local Group, probably lying between the Milky Way and the Sculptor Group. It is likely that NGC 55 and its neighbor NGC 300 orbit each other and form a gravitationally bound pair.

Along with NGC 300, NGC 55 is part of the Local Group of Galaxies that also includes the Andromeda galaxy (M31), the Large and Small Magellanic Clouds, and 40 other galaxies.

NGC 55 is nearly edge-on and appears asymmetrical, like a cigar. Its bulge is diffuse, broad, and somewhat elongated. The bright core is crossed with clouds of gas and dust, and it has a lot of pinkish active star forming regions, and young blue star clusters. Among all these stars are over a hundred Cepheid Variables.

NGC 55 is thought to be like our galactic neighbor, the Large Magellanic Cloud (LMC), although the LMC is seen face-on, whilst NGC 55 is edge-on.

Taken from SWOS in El Sauce, Chile

24” PlaneWave CDK (LRGBHA) Hanson LRGBHa  8-5-5-5-10 Hours

24” PlaneWave CDK (HA) From Matt Dietrich Ha 28 Hours

Total Hours: 61Hours

Image Processing: Mark Hanson

Image Data: Hanson, Dietrich

Thank you,

Mark and Matt