I recently went to a dark site (Bortle 2, near Marysville, Victoria, Aus) with my 18 inch f3.5 and had a few exciting firsts. The site’s at over 1000 m elevation. Here’s a quick report.
I haven’t been to this site since April due to the wet and cloudy winter weather and it’s only my second dark site trip since April, so I was keen! I only started observing at 11 pm, so it wasn’t going to be the longest session.
Transparency appeared good, seeing not so much.
Solar system observations:
Himalia, Jupiter moon m14.4 – My first observation of a Jupiter moon other than the 4 Galilean moons. I managed to prize it out of Jupiter’s glare with a 7 mm Delite. It was interesting to see how much glare there was in my 9 mm APM compared to the Nikon in 10 mm mode and the 7 mm Delite.
Trojan asteroids: 617 Patroclus (m15.6) and 3317 Paris (m15.9) – a trojan asteroid had been on my list for a while, good to find these two. Found both as two faint stars in the right location with the 7 mm delite. My limiting magnitude with direct vision for the night was around m16.1 based on star magnitudes in SkySafari. This was likely seeing limited.
Uranian moons – Found Umbriel, Titania, Oberon and Ariel. Again a first for these as I hadn’t tried for them before.
At the end of the session, I looked at Jupiter and caught an Io transit with the shadow clearly visible as a black pin. I couldn’t see Io itself as it was sitting right on top of one of the cloud bands. View of Jupiter was lovely.
Deep sky:
Had a good look at some old favourites, NGC253 (amazing), 1316 and 1365 with its lovely spiral arms, tarantula nebula. Viewed the Grus quartet – always a favourite with the grouping of 3 close galaxies and the 4th one sitting just a bit off. All four fitted into the field of view of the 22 mm Nagler and 17 mm Nikon.
Sculptor dwarf galaxy – A first for me, got really excited about tracking this one down. It was visible as a brightening of the sky that stayed in the same place when I slewed the scope along. It was best in the 22 mm Nagler. When I looked at pictures of the galaxy afterwards the sky brightening I observed had been in the right location. The galaxy appears to be bound by a grouping of 3-4 brightish stars on one side.
M42 – Amazing in the 17 mm and 12. 5 mm. Thought I saw some colour, maybe bluish-greenish in the centre. What struck me though was how much it affected my night vision. My observing eye was clearly blinded when I looked at the sky. Time to move on to Jupiter and pack up!
At this stage it was late and very cold (4 deg C), but it was great fun.
Great report and some really interesting observing targets. Seems you were quite successful - it’s amazing what some quality dark sky and a big scope can reveal!!