Date: 19./20.1.2017
Time: 20:15-00:00
Observing site: Ulvila Observatory, Finland
Instrument: C280/2750 mm (11” Catadioptric)
NELM: 5.7
SQM: 19.85-20.05
Darkness of the background sky: 3-4
Seeing: 2
Transparency: –
Weather: Some high clouds in the beginning of the session, later the sky cleared up, fresh breeze, surprisingly warm and dry air, only thin layer of snow on the ground, no Moon, surprisingly good conditions considering the time of year
Objects observed: NGC 2194, 2261, 2024, 2175
This was my first observing session in year 2017. During this session, I made four observations, all observed objects were listed in Herschel 400 list. Conditions were relatively good considering the season.
My first object of this session was NGC 2194, an open cluster located in northern part of Orion, near Gemini border. The cluster can be located 1,5 degrees SE from xi Ori. Of this object, I wrote following notes:
@117x: faint-starred open cluster, which is moderately detached, the cluster is mostly visible as a starglow, some individual stars were visible.
My second object of this night was NGC 2261, the famous reflecting nebula known as Hubble’s variable nebula. Of course the nebula itself is not variable, but the star illuminating it is. The illuminating star is R Mon, a variable star of type T Tauri, varying from 10 to 12 magnitudes. This nebula is located in Monoceros, very close to famous Cone nebula, and it can be located ~1 degree SW from the nebula. Of this fascinating object I wrote following notes:
@165x: this famous nebula is known as Hubble’s variable nebula, it appeared surprisingly large and bright, the shape is clearly wedge-like or comet-like, the nebula extends northwards from star R Mon. The star R Mon is like the nucleus of the comet, and the nebula is like the tail of the comet. The nebula was easily visible without filters. Nice object!
My third object of this session was very challenging in thse observing conditions, but nevertheless, I decided to give it a try. This object was NGC 2024, also known as Tank Track Nebula, a famous bright nebula in Orion. This nebula is located very close to Alnitak, zeta Ori. About this challenging object I wrote following lines:
@117x: This nebula was poorly visible in these conditions. The nebula appeared as a very faint, diffuse glow of light slightly east from Mintaka. The nebula was weakly visible without filter, UHC filter enhanced the view slightly. The nebula was visible all the time only with averted vision and sweeping.
This observation left me hungry for more, and I need to observe this one again in better conditions!
My fourth and last object for this session was NGC 2174/2175, an open cluster/nebula in northernmost part of Orion, near Gemini border. This cluster can be located ~1,5 degrees ENE from Chi2 Ori. The name of this object is quite ambiguous, and it is not very clear, which designation is for the nebula and which one is for the cluster. The nebula is also widely known as Monkey Head nebula. Of this object, I wrote following notes:
@117x: a rather scattered, poorly concentrated, poor open cluster. The cluster is weakly detached, with OIII filter I suspected very faint nebulosity around the brightest star of the field.
So know I had finished this observing session. There were two objects, that left me a little bit unsatisfied because of poor observing conditions. These objects were NGC 2024 and NGC 2174/2175. I need to re-observe these objects during next season!
After this, there was one more observing session in January 2017. More about that later!
Celest1al Sphere 