NGC 185, also known as Caldwell 18, is a dwarf spheroidal galaxy located in the southern part of Cassiopeia. It's about 2 Million light-years distant and like neighbouring dwarf galaxy NGC 147 is a satellite of the Andromeda galaxy (M31) and therefore a member of the Local Group. NGC 185 shines at mag. +9.1.

Dwarf spheroidal galaxies are similar to dwarf elliptical galaxies except they are spheroidal in shape, generally of a lower luminosity and recognised only as Local Group satellite galaxies. They are also believed to contain large amounts of dark matter.

NGC 185 (credit - James Gregory Telescope, St. Andrews, Scotland)

Finder Chart for NGC 185 (credit:- freestarcharts)

Finder Chart for NGC 185 - pdf format (credit:- freestarcharts)

NGC 185 was discovered by William Herschel on November 30, 1787. It was first photographed between 1898 and 1900 by James Edward Keeler using the 36-inch (910 mm) "Crossley Reflector" telescope at the Lick Observatory in California, USA.

For a dwarf galaxy, NGC 185 is interesting as it contains an active galactic nucleus (AGN). It's sometimes classified as a type 2 Seyfert galaxy although this is debatable, but if correct, it would mean that it's the closest Seyfert galaxy to Earth and the only known galaxy of this type in the Local Group. Most galactic star formation in this galaxy took place an extremely long time ago.

A good starting point for locating NGC 185 is bright star, Schedar (α Cas - mag. +2.2), in the "W" asterism of Cassiopeia. An imaginary line extending 8 degrees southwards from this star leads to the galaxy. Omicron Cassiopeiae (ο Cas - mag. +4.5) is a degree east of NGC 185 with NGC 147 a degree west of NGC 185.

NGC 185 is within the range of small and medium size amateur scopes. It has an apparent size of 11.4 x 10.0 arc minutes, but visually it appears much smaller. Through an 80mm (3.1-inch) refractor, this galaxy is fairly simple to spot and considerably easier than NGC 147. It appears as a small faint oval patch of hazy light with no obvious centre that covers about 2 to 3 arc minutes. Through larger reflectors, of the order of 200mm (8-inch) or greater, the galaxy is slightly brighter and more defined, especially towards the centre. On good nights, it may be even possible to notice finer details such as surface mottling.

NGC 185 is best seen from the Northern Hemisphere latitudes during the months of October, November and December.

NGC 185 Data Table

NGC185
Caldwell18
Object TypeDwarf Spheroidal Galaxy
ConstellationCassiopeia
Distance (light-years)2.0 Million
Apparent Mag.+9.1
RA (J2000)00h 38m 58s
DEC (J2000)+48d 20m 27s
Apparent Size (arc mins)11.4 x 10.0
Radius (light-years)3,250
Notable FeatureSatellite galaxy of the Andromeda Galaxy (M31)

Sky Highlights - July 2017

The Planets
This Month's Guide

Algol Minima
Algol eclipse dates and times for July

Meteor Shower
Southern Delta Aquariids (Aquarids) meteor shower peaks on July 29

Northern Hemisphere
Evening
West:- Mercury (mag. -0.5 to +0.3) (second half of month)
Southwest:- Jupiter (mag. -2.0)
South:- Saturn (mag. +0.2)
Midnight
West:- Jupiter
South:- Saturn
East:- Neptune (mag. +7.8)
Morning
Southwest:- Saturn
South:- Neptune
Southeast:- Uranus (mag. +5.8)
East:- Venus (mag. -4.1)

Southern Hemisphere
Evening
West:- Mercury (second half of month)
Northwest:- Jupiter
East:- Saturn
Midnight
West:- Jupiter
North:- Saturn
East:- Neptune
Morning
West:- Saturn
North:- Neptune
Northeast:- Venus, Uranus

Deep Sky

Small telescopes:-
Messier 13 - M13 - Great Hercules Globular Cluster
Messier 92 - M92 - Globular Cluster
Messier 11 - M11 - The Wild Duck Cluster (Open Cluster)
Messier 7 - M7 - The Ptolemy Cluster (Open Cluster)
Messier 6 - M6 - The Butterfly Cluster (Open Cluster)
Messier 4 - M4 - Globular Cluster
Messier 8 - M8 - Lagoon Nebula (Emission Nebula)
Messier 16 - M16 - Eagle Nebula (Emission Nebula with Open Cluster)
Messier 20 - M20 - Trifid Nebula (Emission and Reflection Nebula)

Shop at Amazon US

Contributions

If you like the website and want to contribute to the running costs then please do so below. All contributions are most welcome.

PayPal - The safer, easier way to pay online.