Europa

I just came back inside after an hour of stargazing. it's COLD. But wow, the sky is extremely steady tonight. With my 80mm refractor at 170x the airy disks were sharp and steady, and the innermost diffraction ring was seen as three steady, solid arcs.

I looked at Jupiter and its four moons. The clouds were beautiful, but the absolute highlight was the moon Europa. When I started looking at 9.30pm I could only see three moons and an incredibly tiny black dot on top of Jupiter's clouds. but as I kept watching at 170x, at the border of Jupiter's clouds a tiny brighter spot started to appear. Within minutes it was a tiny bright dot, growing out of Jupiter. So Europa was crossing over Jupiter, throwing its shadow on Jupiter, and I caught it just in time to see the moon's disk moving away from Jupiter. I kept watching it as its shadow moved and eventually disappeared. I missed the exact moment of that last event though, as I was also looking at M42 and M43 in the meantime.

M42 and M43 had their beautiful shape as usual. The last time I had seen them was years ago with my 254mm telescope in California, in a much darker location, so it came a bit as a surprise that I could only see 4 stars of the trapezium with my 80mm telescope here. So I didn't even see E and F (both around magnitude 10.3). The A, B, C and D stars were all bright though (but then the dimmest of them is only around magnitude 8). With my 254mm telescope I remember I could always easily see 7-8 stars, which means I had no trouble reaching magnitude 14.5. Without nebulosity, high in the sky, I actually have notes that say I also saw magnitude 15.5 stars with it.

I only stayed outside for an hour, came back inside at 10.30pm, and only looked at these objects.

Tonight was the first night I used my new TeleVue 2x Powermate. The refractor doesn't reach focus if I place it in front of the diagonal, so I have to place it after the diagonal. Its barrel cannot be moved completely in it, so the setup is not exactly parfocal as I had intended. Compared to my Meade 2x barlow it is very heavy, but the resulting image is brighter, has more contrast and less flaring. Jupiter and M42 just looked darker and not as sharp with the barlow. But because switching the setups takes time, I didn't do a very detailed comparison. I did notice that the magnifications do not seem to match. It looks like the setup for the barlow results in a slightly lower magnification than expected.