Observing site: Ulvila Observatory, Finland
Instrument: C280/2750 mm (11” Catadioptric)
Darkness of the background sky: 3
Weather: Clear sky, calm, no Moon, no snow, 0 – -2C, aurora belt/arc in northern sky
Objects observed: NGC 3640, 3641, 3810, 3655, 3900 and 3912
This night was my last observing session in March 2017 and in observing season 2016-2017. During this night, I observed several galaxies in Leo, and I was able to finish Leo constellation in Herschel 400 observing list. During the night, I was observing in Ulvila observatory, and conditions were relatively good in terms of the site.
NGC 3640, 3641
My first stop at my journey in the starry sky during this night was pair of galaxies NGC 3640 and 3641. Of these two, my main target was NGC 3640, an elliptical galaxy located in southern part of Leo. This galaxy can be found when moving ~degrees south from sigma Leo. NGC 3641 is located only 2,5′ SE from 3640. This galaxy is rather faint and small, and it is classified also as an elliptical galaxy. Of these two I wrote following notes:
@165x: two galaxies in the field, NGC 3640 and 3641. NGC 3640 is the brightest and more dominant of these two. NGC 3640 appears as a bright, oval-shaped, diffuse glow of light with bright non-stellar core, long axis in W-E orientation. NGC 3641 appears as a small, roundish, featureless and faint nebulous patch slightly SE from NGC 3640.
NGC 3640 and 3641 observed with 11” Catadioptric
My next object for this night was NGC 3810, a galaxy located in southern Leo close to Virgo boundary. This galaxy can be located when moving ~4 degrees ENE from iota Leo. This galaxy with beautiful spiral structure has also been photographed by Hubble space telescope. This galaxy is classified as an Sc -type spiral galaxy, and the galaxy has a really nice spiral structure, see for your self! Unfortunately I couldn’t see the spiral structure with my modest instrument. About this galaxy, I wrote as follows:
@165x: this galaxy appeared as a rather faint, roundish and diffuse patch of light, the galaxy has a faint core, which doesn’t stand out much.
NGC 3810 observed with 11” Catadioptric
My third object for this session was NGC 3655, an Sc -spiral in the rear end of Leo. This galaxy can be located for example by moving ~2,5 degrees NE from theta Leo. About this galaxy, I wrote following notes:
@165x: this galaxy appeared as an elongated, oval-shaped glow, the galaxy has a rather bright core, long axis in N-S orientation.
NGC 3655 observed with 11” Catadioptric
My fourth object for this night was NGC 3900, a spiral galaxy of type S0-a R, located in north-easternmost corner of Leo, close to Coma Berenices boundary. It can be located for example by moving ~8,5 degrees roughly to west from gamma Com. About this galaxy I write as follows:
@165x: rather bright, oval-shaped, elongated galaxy, rather bright core, long axis in N-S orientation.
NGC 3900 observed with 11” Catadioptric
My fifth and last object for this session was NGC 3912, a barred spiral galaxy of type SBb, located only ~30′ SSE from NGC 3900. About this galaxy, I wrote as follows:
@165x: this galaxy appears as a faint, diffuse, nebulous and featureless patch of light. This galaxy is elongated and thin, long axis in N-S direction.
NGC 3912 observed with 11” Catadioptric
So, that was it! My last observing session in March 2017 and last in observing season 2016-2017. Now I had finished Leo constellation on Herschel 400, and I could tick off that constellation from the list!
This observing season had been also quite productive, I was able to more than 80 observations during the season! In late season during spring of 2017, I was having quite busy and hectic season again in my life, and that hindered my observing to some extent. I had to terminate the observing season prematurely partially because of that. But all in all, I was quite satisfied with my observing season! I might later publish a more detailed insight to my observing season statistics.
But at least I’m going to keep some time off from observing because of the mandatory summer break that we northern deep sky observers have. The skies are already very light, and it’s only about 3 weeks to summer solstice! Enjoy the summer, and have good time! See you again in Autumn of 2017!