M51 Whirlpool Galaxy (Rev. 1)

Spiral Galaxy in constellation “Canes Venatici”

Project #6

M51 – Object Description

The Whirlpool Galaxy, also known as Messier 51a (M51a) or NGC 5194, is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus. It lies in the constellation Canes Venatici, and was the first galaxy to be classified as a spiral galaxy. It is about 31 million light-years (9,5 Mpc) away from Earth and 76.900 ly (23.580 pc) in diameter.

The galaxy and its companion, NGC 5195 are easily observed by amateur astronomers, and the two galaxies may be seen with binoculars. The Whirlpool Galaxy has been extensively observed by professional astronomers, and its pair with NGC 5195 who study it to understand galaxy structure (particularly structure associated with the spiral arms) and galaxy interactions. Its pair with NGC 5194 is among the most famous and relatively close interacting systems, and thus is a favorite subject of galaxy interaction models.

M51 – Project Publications

Image Publications

Please find all project-related image publications for this revision below.

M51 – Project Findings

Having a closer look on [Image 1], you will find various faint galaxies like in my last project, NGC7023 Iris Nebula. If you’re interested – I wrote a short essay in its project page on how I was able to identify it.

So, making use of that knowledge I’ve combined all automatically retrieved annotations with my own to enrich the following [Image 2];

Let’s have a look into the yellow-ish labelled galaxies, that I added manually (data below was researched with NED);

The bright star to left of M51 Whirlpool Galaxy is HD117815, a pulsating variable star. I’ve looked it up in Stellarium – it’s 371,05 ly away from Earth and spectral-classified as “A5V”. That means HD117815 has about 1,86 solar masses (in relation to our sun) and a solar radius of of 1,79. It’s effective temperature is 8.100K which equals 7826,85°C (Source: Wikipedia).

M51 – Project Details

Please find all project-related details for this revision below.

I would like to thank my friend Daniel Nimmervoll for the great workshop where the final revision above was created.