Welcome to the next episode of my series about amateur observations of celestial bodies. Continuing the journey through the brighter galaxies of our sky, I would like to show you an interesting spiral galaxy, which we are able to see from the countryside with a telescope for around $300. Let's look at the galaxy marked in the Messier's catalog number 108.
By Sloan Digital Sky Survey link [CC BY 4.0 license]
In the constellation of Ursa Major there is at least some interesting objects. Some time ago I was describing to you the Owl nebula (M97), it is in its vicinity is the galaxy M108. We'll find her near the bottom of the Big Dipper. More precisely about 1 degree from the Merek star, visible on the map below. Both M108 and M97 have a similar brightness of around +10 magnitude, so they remain invisible to the unaided eye. In order to be able to see that these objects, we need a dark, rural sky during the new moon and 10 X 50 binoculars. Meeting these conditions will allow us to see both objects simultaneously in view. M97 will not be sharp, like a fuzzy star, and M108 will appear as a poorly visible. For the thirsty for real sensations, however, you need a stronger instrument, a telescope with a lens diameter of at least 8 inches (200 mm).
By IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg) link [CC BY 3.0 license]
For telescope owners, the size of the galaxy will be quite large, because it occupies an area of 9 X 2 arc minutes in the sky, for comparison the full Moon has a 30 arc minutes in the Earth sky. Using the smallest magnification with a wide-field eyepiece will allow you to see M97 and M108 together. This duet of nebula and galaxy is one of the coolest pairs of objects in the sky. In such a small magnification, the view resembles the one known from binoculars, but in the telescope we are sure of what we see: a fuzzy sphere and a fuzzy line. When we can get away from large cities and have a large 12-inch (300 mm) telescope or larger, a real feast awaits us. I saw a similar view to the simulation below in 2013 with my GSO 12-inch telescope during the astronomical rally in Roztoki Górne in the Polish Bieszczady mountains. The galaxy, at high magnification, showed its structure, dark matter bands and a few brighter stars visible in its background. To this day I remember this view, a distant object in such a quality, we see it as it was many millions of years ago.
(My modification) Original by Hewholooks link [CC BY-SA 3.0 license]
It is estimated that the M108 galaxy is located about 45 million light-years away from Earth, which is why we see it as it was 45 million years ago. M108 is moving away from us at a speed of 772 km / s. As you can see, galaxies are constantly changing their location. In galaxy M108 a supernova was observed. SN 1969B was observed in M108. On January 23, 1969, she reached the brightness of +13,9 magnitude (it was a very weak star, visible in the background of this galaxy only in large instruments). I hope that I have inspired some of you to be interested in the cosmos that opens over our heads every cloudless night.
