Coming out of the full moon time and before I started a run of support nights for work, there was a window for observing: a night where the moon would not rise until about 10:40 PM local time. The forecast was clear of high clouds, but it had been very windy recently. Looking at the detailed wind forecast allowed for some optimism as the saddle area might be protected given the prevailing wind direction, so I packed the car and headed out. It turns out going was a good choice.
I stopped at a pullout along the Mauna Loa Access Road which was lower down than I usually choose. Before sunset, the clouds were low and the pullout had a low ridge to the East. Since I had was concerns about wind from that direction I decided to try this site despite it being about 500 feet lower elevation than my usual sites. Observing lower down is always risky since the inversion layer can rise and cover the site with clouds, but I thought it would be worth the risk to avoid winds which were more likely higher and further to the East on the mountain. Around sunset the inversion layer clouds crept up and almost reached the site, but they dropped and never actually covered us. Winds were light, so it was a nice night for observing.
With only about 3 hours of full darkness between the end of astronomical twilight and the arrival of moon glow, this would be a short session. I'd prepared a few more of my constellation lists which contain deep sky objects (galaxies, globular clusters, bright nebulae, planetary nebulae, and quasars) brighter than magnitude 12 in a particular constellation. I've found these observing lists to be a lot of fun as the magnitude limit keep things well within reach of my 152mm refractor and I sometimes come across new gems which I'm not familiar with.
Tonight, I decided to hit a constellation with particular significance to me: Perseus. My PhD dissertation focussed on outflow activity in the Perseus Molecular Cloud, so I would be seeing a few familiar objects along the way. I'd checked out a few of these last month, but I wanted to finish out the constellation.
One of the early challenges was the Perseus Galaxy Cluster. This contains two objects on my list (the rest are fainter than magnitude 12). The brightest member (NGC 1275 or Perseus A) was relatively easy. The second brightest member (NGC 1272) was surprisingly difficult to spot. I think this is because while the integrated magnitude is bright, the galaxy is large, so the surface brightness is low. I did eventually spot it, but it took some time. I thought this would be all I could see in the galaxy cluster since the other galaxies are fainter, but while looking for 1272, I found several other members of the cluster: NGC 1273 (mag 13.1), 1277 (mag 13.4), & 1278 (mag 12.4). These were fainter, but more compact making them easier to see despite their faintness.
Taking a break from chasing faint galaxies, I chatted a bit with Mike Connelley who was observing nearby. While chatting I was just doing some naked eye stargazing and I realized that I had never tried to see M33 (the Triangulum Galaxy) with the naked eye. I'd heard observers claim to detect it under dark skies and this would be a good opportunity. I couldn't remember the exact position, but I thought I could see a faint fuzz at about the right spot. Sure enough, when I later compared that position with a chart, it was in exactly the spot I'd thought it was. This is the furthest object I've seen with the naked eye. At about 2.7 million light years, it is just a bit further away than the Andromeda Galaxy (M 31).
Returning to the eyepiece, I then moved West to East through the Perseus Molucular Cloud, starting with NGC 1333 (which I mentioned last month). I cruised through the dark clouds of Barnard 1, Barnard 4, and Barnard 5 and finished with the cluster and nebulosity IC 348. This was the region of sky which I'd spent a lot of time observing while writing my PhD dissertation.
I finished out Perseus with a few more galaxies and a couple of very small planetary nebulae. I then moved on to visit a few old friends in Orion (primarily M42), but I also stopped by the Horsehead Nebula again. With Orion much higher in the sky than last month, the Hosehead was much easier to spot.
A quick look at the rapidly receding Mars as the moon rose concluded the night.