Whirlpool Galaxy

Main Objects: Messier 51, NGC 5195, IC 4263, IC 4278, AT 2019ABN

The best known interacting galaxy pair

M51
M51 map
M51 annotation

Galaxies are densely located in the night sky of the spring months. It can take several years to capture the most beautiful galaxies in this season. In the spring of 2019, I decided to turn my reflector towards an object that I had photographed earlier. This object is the famous interacting Whirlpool Galaxy at 25 million light-years away. Its Hungarian name is false Whirlpool Nebula - due to the traditional name of deep sky objects, when they didn't know it is a galaxy.

Its discovery is linked to Charles Messier, who discovered the brighter member of the galaxy pair in 1773. This spiral galaxy is slightly smaller than the Milky Way and has an active galaxy nucleus. The strong light of the active galaxy is also visible in my photograph. 
The harsh appearance and distortion of the spiral arms is due to collisions with the NGC 5195 galaxy. Their first encounter was about 500 million years ago, and their second collision was a few million years ago. At the moment, NGC 5195 is behind Messier 51, but the gravitational attraction and tidal bridge between them will pull back to Messier 51 and become one galaxy in the future. These types of galaxy pairs are called interacting galaxies.

NGC 5195 was discovered in 1781 by Messier's friend Pierre Méchain. The spiral structure of the initially spiral galaxy is now difficult to recognize, as it is significantly distorted during the collisions with Messier 51. From the Earth's perspective, the tidal bridge between the two galaxies overlaps a small part of NGC 5195, giving us even more unusual sight. The structure of the dust surrounding the galaxies also shows the power of collisions.

The small 14.5 magnitude galaxy near the lower right corner is the IC 4263 spiral galaxy. Its distance is about 123 million light-years.

An interesting feature of the photo is that an unexpected guest appeared in the M51 galaxy. AT 2019abn, which was discovered on January 22, 2019, has not yet been classified as Intermediate Luminosity Red Transient (ILRT) or reddish Luminous Blue Variable (LBV). Its brightness around 17.3 magnitude, so it is clearly visible in the images

Name:

Whirlpool Galaxy, Messier 51, M51, NGC 5194

Constellation:

Canes Venatici

Coordinates:

R.A. 13 h 29 m 53 s Dec. +47° 11′ 44″

Type:

Spiral galaxy - SA(s)bc pec

Distance:

25 million light-years

Brightness:

8.4m

Apparent size:

11' x 7'

Size:

60,000 light-years

Observable: 

Spring and summer

Date:

30/03/2019

Total exposure time:

6.25 hours

Location:

Tápióbicske, Pest, Hungary

Camera:

Canon EOS 1300D (modified)

Telescope:

Home-made 200/800 mm Newtonian reflector

Mount:

Sky-Watcher EQ6-R Pro GoTo

Guiding:

Lacerta MGEN-II

Corrector:

Sky-Watcher f/4 coma corrector

Focal ratio, length:

f/4, 800 mm

ISO:

800

Light:

75 x 300 s

Dark:

10

Flat:

10

Bias:

10

Processing:

Astro Pixel Processor, PixInsight, Adobe Lightroom, Adobe Photoshop

Location

Annotation

Name:

Whirlpool Galaxy, Messier 51, M51, NGC 5194

Constellation:

Canes Venatici

Coordinates:

R.A. 13 h 29 m 59 s Dec. +47° 15′ 58″

Type:

Spiral galaxy - SB0 pec

Distance:

25.5 million light-years

Brightness:

9.5m

Apparent size:

4' x 4'

Size:

42,000 light-years

Observable: 

Spring and summer