Location: The Back Garden
Weather: Clear skies, bit chilly for the time of year.
22:00 For the first time in ages I saw the Moon. I could see it peeking through a gap between the trees. Got the scope out and set up with some urgency as I knew there wasn’t much time. By the time it was set up it was just coming out from behind the fir tree and I’d probably got about 15 minutes before it went behind the next one. It was very low, probably about 30deg. The plane of the ecliptic is quite low during summer.
The Moon was just over 1/2 phase so I looked for interesting features near the terminator. I picked on the crater Gassendi on the northern edge of the Mare Humoroum. It’s a great looking crater with a central peak. Directly opposite on the southern edge or Mare Humorum is a flooded crater, the baylike Doppelmayer.
The image below is a screenshot from the Moon HD app on the iPad.
I’ve started doing the Lunar 100 and Gassendi is #13 on that. Sounds daft but I’m starting from scratch as as I haven’t seen the Moon for ages and that takes my tally to 2/100 observed.
And with that it was behind the tree again, but not before I got A out to take a look. People are always impressed to see detail on the moon through a scope.
22:15 I turned my attention next to the Summer Triangle, and in particular the constellation Lyra. Took a look at the double star epsilon Lyra. It’s actually a double double. I think I just about managed to split them both with a 10mm eyepiece.
Last weekend I bagged my first Messier object, M57, the Ring Nebula. I’m trying to spend time on each object rather than spot as many as I can, as quickly as possible, so I’ve been returning to it in my observations this week. Part of my reasoning is to familiarise myself with and to learn an object better by focussing on a small area of the sky. The other reason is that living in a city I have to contend with light pollution, street lights overlooking my garden, surrounding buildings and a lot of trees so the area of sky available to me is pretty much overhead and a bit to the north and a bit more to the south. This limitation can be frustrating but also means I can’t just go jumping all over the sky.
Really getting familiar now with Lyra and after my first attempts at star-hopping that took about 2 hours to spot, I was able to find M57 quite quickly. The Ring Nebula was quite difficult to see this evening. It was starting to get a bit hazy and the seeing wasn’t great – a bit ripplely. It was more obvious through the 25mm. I was able to get a cleare view sometimes with the 17mm Plossl but only with a bit of averted vision or when I tracked across the region. Then it would kind of pop in and out of view. It’s a fine sight, like a smoke ring. At first I wasn’t sure I’d got it but after returning several times in the last week, it’s a familiar and recognisable sight now.
I also tried a light pollution filter. Whilst it seemed to take out some of the orange glow, I’m not sure if it made the nebula clearer or not. But then I’m not sure if it’s supposed to enhance the view of a planetary nebula such as this.
Whilst moving away from and returning to M57 during this session I made myself familiar with the stars around beta Lyra, Sheliak, and gamma Lyra, Sulafat. M57 lies between these two.
I’ve just started playing with Sky Safari (more on that in a later post) so have matched what I sketched very poorly with what I was seeing around each of these as below.
There’s a line of three stars leading away from Sheliak, and Sulafat forms a triangle with two other stars.
23:25 It was getting cold by now. I was about to pack up and then noticed the Moon was just peeking through a low gap in the trees to the SSW. Took a final look at Gassendi. Noticed a further smaller crater on the northern wall of Gassendi. This was Gassendi A. Together they make what’s known as the diamnd ring.
Astro Ukenaut 