Observing Log for 2007-04-04
www.astronomer.me.uk

Observing Logs

Latest Log
Related Links

2007-04-04


Location: Billingborough (South Lincolnshire, UK)
From: 2007-04-04 15:10 UT
To: 2007-04-04 15:15 UT
Equipment: Solarscope
Temperature: 10.8C ...
Dew Point: 4.6C ...
Humidity: 66% ...
Wind Speed: 0.8mph ...
Wind Dir: North ...
Pressure: 1022.6hPa ...
Notes:

Mostly cloudy day. Started to clear some later into the afternoon so took the Solarscope out to do a quick sunspot count.

Sun

From: 2007-04-04 15:10 UT
To: 2007-04-04 15:15 UT

No spots or other marks visible on the Sun.

Location: Billingborough (South Lincolnshire, UK)
From: 2007-04-04 19:19 UT
To: 2007-04-04 20:48 UT
Equipment: Sky-Watcher Explorer 130M
Temperature: 7.1C ...
Dew Point: 2.9C ...
Humidity: 75% ...
Wind Speed: Calm ...
Pressure: 1022.2hPa ...
Notes:

The day cleared further and resulted in a pretty nice evening. I decided to get the 130M out and have a look at Venus with it.

Venus

From: 2007-04-04 19:19 UT
To: 2007-04-04 20:05 UT

I'd put the 130M outside about 20 minutes earlier in the hope that it would cool off enough. Having only used the 905 to observe Venus I was keen to have a go with the 130M.

I first lined the planet up with the 25mm eyepiece. The planet seemed very bright and I could see four huge diffraction spikes coming off it. It was almost impossible to see any shape to the planet itself.

Next I switched to the 10mm eyepiece. I could now see some hint of shape but the planet was still very bright and was still mostly obscured by spikes.

I then switched to the 6mm eyepiece. Despite it being too bright a view still, and despite it still being marred by spikes, I could now easily make out the phase. I was also very surprised at how large the planet looked (the 6mm in the 130M gives 150x magnification).

In an effort to improve the view I placed the end cap of the 'scope back in place and removed the cap from the small aperture. This made a huge difference. The view wasn't anywhere near as bright and I was no longer bothered by spikes (for obvious reasons). While the view wasn't crisp, there was a well defined gibbous phase visible.

Next I added the barlow. The view was very soft with some false colour, not the best view but pretty magnificent when compared to the view via the 905.

I did some more experimenting, adding filters and the like, and found that a good view could be obtained with the 6mm eyepiece (no barlow), the ND25 filter and the cap in place (with the smaller hole open, obviously). While the image was still a little soft around the edges, and gave the odd hint of a red and a blue from time to time, it was a very good view.

As a comparison I then tried the contrast booster and the #80A medium blue filters with the 6mm (still with the cap in place). This also worked well (as I've found on the 905).

In all the experimenting I did none of the images I had appeared to be the sort of image that would allow me to do any sort of "serious" observation, I can't imagine managing to make the sorts of observations that avid Venus observers do. I will, with either 'scope, be able to follow the phase changes though.

At 20:05 UT I finished with Venus.

Saturn

From: 2007-04-04 20:10 UT
To: 2007-04-04 20:48 UT

Given that it was well placed and I had the 130M out I decided to move on to Saturn.

I first got the planet lined up in the 'scope with the 25mm eyepiece and I then switched to the 10mm eyepiece. The view was amazing! Easily as good as, if not better than, the best view I had last year. The Cassini Division stood out right away, there was no problem seeing it. I could also clearly see the shadow of the rings on the planet and the shadow of the planet on the rings. I could also see, without any real effort, some faint banding on the planet itself.

Keeping in mind all the problems I had in the past with the old barlow and the 10mm eyepiece I added the barlow to the mix and looked again. The view was stunning and there was no problem finding focus. There's little doubt that this barlow works far better with the 130M than the one that was supplied with the 'scope.

I then mixed the 6mm eyepiece with the barlow. The view was a little soft but I could see obvious variation in the rings, the Cassini Division stood out and the banding on the planet was still visible.

I noted that this must have been an exceptional sky tonight as I appeared to be getting better and more consistent views than I've ever had before.

Back on the 6mm with no barlow, I noticed to the left of the planet, about a ring diameter away, I could see a faint "star". Checking later with Starry Night is seems that this was Rhea. To the right of the planet, much further out, I could see Titan.

I spent more time just looking at Saturn, watching the really clear moments, the really steady moments, pop in and out of view (and there were many of them). Finally, at 2007-04-04T20:48Z, with some thin cloud starting to get in the way of the view, I decided to pack up for the night.


Page last modified: 2013-04-09 09:19:19 UT
Dave Pearson <davep@davep.org>
Valid XHTML 1.1 Valid CSS