Astronomical Observations #29: Messier 100

astromaniac (59)in #steemstem • 5 years ago (edited)

In the next episode of my cycle devoted to the observation of celestial bodies, I would like to show you an interesting spiral galaxy in the constellation of Coma Berenices. M100 lies at a distance of about 56 million light years from us. The diameter of this galaxy is estimated at around 120 thousand light years. Below is a photograph of this object taken by the European Southern Observatory.

Galaxy M100: A photo with a long exposure time

_{By ESO link [CC BY-SA 4.0 license]}

Messier 100 is a galaxy with a fairly low brightness of +9.4 magnitude. According to the brightness scale, the range of the human eye in good conditions is +6 magnitude, and the average 10 X 50 binoculars allow you to see stars up to +10 magnitude. Unfortunately, stars are points, and the M100 occupies an area of 7 X 6 minutes of angle in the sky. Therefore, with such a low surface brightness, this object is rather only within the range of telescopes. In small instruments we will only see a bright kernel. Of course, we are only talking about observations from rural areas. Underneath the city this object is inaccessible even for large telescopes. To find the M100 in the sky, you have to move about 8 degrees (the width of the thumb stretched out towards the sky measures 2 degrees) east of Denebola, a star of brightness +2 magnitude in the constellation of Leo. The galaxy's disc is perpendicular to us, so it presents its spiral arms very well. A very dark sky like in the Polish mountains of the Bieszczady Mountains and a telescope with a diameter of more than 12 inches (300 mm), allows you to see views of the M100 as simulated below. Such a live view is really amazing. Keep in mind how far this object is from the Earth and is available for amateurs.

Simulation of the M100 galaxy view in a large amateur telescope under a dark rural sky

_{By ESO/IDA/Danish 1.5 m/R. Gendler, J.-E. Ovaldsen, C. C. Thöne and C. Féron (My modification) link [CC BY-SA 4.0 license]}

The Messier 100 spiral galaxy is probably made up of around 100 billion stars. Photos of the M100 with a long exposure time show two large spiral arms. There are also bands of black dust. New hot stars are born in the main two arms, some of which will probably explode in the future in the form of supernovae. I must admit that I recommend this object to more experienced observers. In good conditions, this galaxy can surprise every observer with its beauty. Galaxies are the most distant objects visible in amateur telescopes. Hunting a galaxy requires a lot of sacrifice. We have to leave urban areas and find rural areas without artificial lighting. When we manage to find such a place and we have a large telescope, the views we will see will be an incredible reward for us. The true universe will reach our eyes. I recommend going to an astronomical rally to experience it.