Last night members of my society, Macclesfield Astronomical Society hosted a "Jupiter" watch at Kerridge Cricket Club, Bollington. I am the society's observation co-ordinator, and decided last month it would be a good idea to get together in a public place to show members of the public, and our beginners to astronomy, Jupiter.
This event was, despite the annoying cloud, a success. We had a total of five telescope's set up ranging from my Orion (UK) 10" a 7.5" Mak-Newt a 6" SCT an 8" SCT and our chairman's Andrew Greenwood's 12" Meade Light Bridge.
Because of the slight haze in the sky, the seeing was for once superb. I estimated it to be Antoniardi (ANT) two. The Ant numbering is the scale used for judging the seeing conditions for the night. ANT 1 is excellent whilst 5 is very poor (why are you out side)
And because the seeing was very good, Jupiter was very sharp when viewed with a good high power eyepiece. At one time last night, I had the planet at x300 (4mm Vixen LV) but my best views of the planet were at x160 (7.5mm Plossl)
I said the planet was sharp, and what a view! When Jupiter came into view and rose higher in our sky the view's were simply stunning. I saw clearly the GRS which was very bright pink to my eye, together with the shadow of Io and various cloud features.
Later in the evening towards midnight. We were treated to a view of Io, that nobody could have predicted or have ever seen before. The moon was suddenly visible before it broke free of the planet, and we watched as Io slowly separated from Jupiter. The view is hard to describe; Io was a tiny disc that looked iridescent against the backdrop of Jupiter's invisible South equatorial belt, it really was an amazing sight through the telescope.
The evening was a great success and, with luck, I hope to be there again tonight for stage 2 of our Jupiter watch; sadly though the weather doesn't look fantastic for tonight, but you never know.
Here is a report from the Chairman of Macc Astro, Mr Andrew Greenwood.
Chairman's note: As Paul has mentioned, the event was extremely successful, it was very gratifying to be treated to some wonderful views. It has been a long, long time since Jupiter has looked so good through a telescope at our latitude.
The changing sky itself was quite dramatic. The veil of Cirrostratus produced a number of subtle optical effects. We saw a paraselene (moon-dog) and part of a 22 degree halo, upper tangent arc and upper and lower Moon pillar. All three are infrequent night-time displays. The most striking optical effect was telescopic. Looking at Jupiter it was clear to see a beautifully coloured, oval-shaped halo around the planet. As Paul has mentioned, the seeing was amazing. The GRS and inky-black shadow of the transiting moon was striking. It has been a long time since the GRS appeared so orange/red. I expect this is because of the absence of the SEB. A multitude of subtle details were visible within the polar regions of the planet, and even after the GRS had exited the disk, there was a large oval in the NEB, which to my eyes had a very defined dark area, much smaller than the transiting shadow.
After waves of thicker Cirrostratus came and went, something miraculous occurred. The sky became ultra-transparent. The Milky Way burst into view straddling Perseus, Cassiopeia and into Cygnus. No telescopes were required to see the Double cluster and the great Andromeda galaxy, M31 - or to just gaze at the countless majestic stars.
The final target for the night was 2.5 billion miles away from where we were standing. It was Uranus. The pale green, glimmering disk of the distant planet was clear to see. All the more amazing was its line-of-sight proximity to Jupiter - it was only 0.5 of a degree from the giant planet, but separated by two billion miles ... Wonderful!
Upon returning home, I took one last lingering look at the Milky Way, hopefully anticipating the brief appearance of a meteor. Unfortunately, it wasn't to be. Still, I felt very happy with the wonders I had witnessed.
Congratulations to Paul for organizing a very successful observing evening. I very much hope there will be many more.
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