Noctilucent clouds, SQM -measurements, Jupiter and variable stars

Observing session #3/11-12

During couple of last nights I was making some observations. During the night 29/30.7.2011 I was making observations in Turku. First at 01.00 I checked the NLCs from the Kerttulinmäki -hil, and indeed there was a small display going on in the northern sky. The display was restricted to small area in the northern sky and the maximum height of the display was 20 degrees. I also made measurements with SQM, and I got readings of about 17,68. NELM was about 4.0.

Then later that night I went into Kupittaanpuisto park to see, whether it is possible to do any observations from there. I noted, that it is possible to do some observations, although the place is very light polluted. Besides planetary- and lunar observations, it is possible to do observations of variable stars and of the brightest DSOs.

In Kupittaanpuisto, I was watching Jupiter and I also made my very first observation of a variable star! The star of my choice was R Cyg, which was shining with magnitude of about 10. While observing, I faced some difficulties. First of all, the sky was still very light, and there was also some light pollution in the area. Also there were some drunken people walking in the park once in a while which was causing some interference. And I also had printed accidentally wrong kind of maps for R Cyg, which was also a small problem. But anyway, I was able to make the observation!

Summary of obs session #3/11-12
Date: 29/30.7.2011
Time: 01.00-03.30
Place: Turku, Finland
Instruments used: L102/1000mm, naked eye
Objects observed: Jupiter, R Cyg, NLCs
Conditions: NELM: 4.0, SQM: 17.78, partly cloudy, light sky, warm air

Observing session #4/11-12

The observing session of last night (30./31.7.2011) was clearly more successful. This time I went into my favourite dark sky -observing place in Parainen, in the Archipelago of Turku. This time there was some butterfly -collector with his light trap, which was causing some point -type light pollution. Actually I saw the same guy once also in august of 2009. Luckily I was able to hide his light when I went into the sandpit in my observing place and it it wasn’t causing any interference.

Also during the last night, there was a beautiful NLC display at low altitude in the northern sky. This time the display was quite bright, and it was there during the whole night.

Then I also made some observations of the observing conditions. At 01.40, when the night was as dark as it gets, I was getting readings of 18.84 and I estimated that the NELM was about 5.0. During the darkest moment of the night, the altitude of the Sun was about -11, and thus it was still only nautical twilight. But still, it was dark enaugh to start doing some observations. This time I was also making observations of NLCs, variable stars and Jupiter.

The stars that I observed this time were R Cyg, R CrB and Z And. I re-observed R Cyg because the last time when I tried to observe it there were so much difficulties and interfernce that I wanted to be sure about my observation was correct. I was able to make only negative observation of R CrB, because it was fainter than 11.9, which means that it is now at least near its minimum!

Noctilucent clouds in the sky of Parainen, 30./31.7.2011

Summary of obs session #4/11-12
Date: 30/31.7.2011
Time: 00.20-03.30
Place: Stormälö, Parainen, Finland
Instruments used: L102/1000mm, naked eye
Objects observed: Jupiter, R Cyg,R CrB, Z And, NLCs
Conditions: NELM: 5.0, SQM: 18.82, clear, light sky, +14 C

This time there will be no pics, but I will add them later!

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