Galaxies

A Note on Naming – Most, if not all, Astronomical objects have several names or designations depending on the type of object it is. The most popular objects often go by a popular descriptor, name, or moniker such as “The Pinwheel Galaxy” or “The Sombrero Galaxy”. For galaxies you will most often find them identified by a Messier, NGC, or IC number which are defined below:

  • M – “Messier Number” – The Messier Catalog is a list of 110 astronomical objects which was first compiled in 1774 by French astronomer Charles Messier. The list contains most deep-sky objects that can be easily observed from the Northern-Hemisphere.
  • NGC – “New General Catalog” – A catalog of 7,840 astronomical objects (Galaxies, Star Clusters, and Nebulae) first compiled in 1888. It should be noted that all of the Messier objects have a NGC designation as well.
  • IC – “Index Catalog” – A supplement to the NGC catalog describing a further 5,386 astronomical objects published in 1895.

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The Andromeda Galaxy (M31) is the largest galaxy of the “Local Group” which is comprised of 54 Galaxies of which our own Milky Way galaxy is a member. It is the most distant object that can be seen with the naked eye at 2.5 million light years and contains approximately one trillion stars. Our own galaxy – “The Milky Way” – is the second largest  member of the Local Group and is roughly half the size of M31.
The Triangulum Galaxy (M33) is the third largest member of the Local Group of galaxies and is located 3 million light years away.
This photo shows two colliding galaxies, M51 & NGC 5159. You can see the bridge of gas streaming between the two galaxies as a result of the interaction.  Our own Milky Way Galaxy and the Andromeda Galaxy will have this same sort of interaction 4 billion years from now.
This small cluster of three galaxies is located in the constellation of Leo and is 35 million light years distant.  All three members are spiral galaxies with NGC 3628 being viewed nearly edge on.
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M82 is also known as “The Cigar Galaxy” and is 12 million light years distant. It shines at magnitude 8.2 and has a rate of star formation that is ten times larger than our own Milky Way galaxy.
M100 is an spiral galaxy located 55 million light years away with a diameter of 107,000 light years. It is located in the constellation Coma Berenices.   Four fainter spiral and elliptical galaxies are in the field-of-view.
Known as the “Pinwheel Galaxy”, M101 is 21 million light years distant in the constellation Ursa Major (The Big Dipper).
M104, popularly known as the “Sombrero Galaxy” is 31 million light years distant and 50,000 light years in diameter – about 1/3 the size of our Milky Way galaxy.   The stars in the field-of-view are foreground stars in our own galaxy.
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The “Twin Quasar” is an example of “Gravitational Lensing”  – in effect it is an Interstellar Mirage.  The double image of QSO 0957+561 is created by an intervening mass concentration located between the earth and the quasar (Galaxy YGKOW G1) which bends the light from the quasar creating two separate images of the object.  The time of arrival of the light from the two images differs by 417 days.  At 7.8 Billion light years away it is the most distant object that I have photographed.
The Edge-on Spiral Galaxy NGC4565 – also known as the “Needle Galaxy” in the constellation of Comae Berenices.
The Galaxy NGC 6946 in the constellation of Cygnus is also known as “The Fireworks Galaxy” due to the colorful spray of stars that adorn the field of view. The galaxy is 40,000 light-years across and 100 million light-years distant. the galaxy has been very active with nine supernova observed within its boundaries since 1917.
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