Mercury Transit, Jupiter, Mars and Saturn, May 9, 2016 – Observing Report


Monday, May 9, 2016 started as most mornings have lately with mostly cloudy skies. Of course the weather folks all seemed to say what a glorious day it would be, with a few clouds, and lots of sunshine. Undeterred, I went out on multiple occasions with my Lunt 8X32 SUNoculars to take a look at the progression of the Mercury transit. Nada, nothing, just a good sized sunspot, when I could see the Sun between the clouds. The clouds finally gave way to the sunshine as it passed 10:00 AM. So I took my Coronado PST outside and set it up. Hey, what do you know, dead batteries! After replacing said batteries I set it up and easily saw Mercury transiting the Sun. This was my first time viewing a Mercury transit, so I was still surprised at how small it was, given that it was 36 million miles closer to Earth than old Sol. Venus looked so much bigger when it was transiting the Sun. With that knowledge in hand, I took my trusty SUNoculars out, braced my arms as much as I could on my vehicle, and tried once more to view Mercury with them. Finally, I succeeded in finding Mercury. Boy, was it small dot!

After that, I stayed with the PST. There wasn’t much solar activity, other than the sunspot. Though there were a few small prominences, some faculae, and some mottling (or granulation) visible. The show was Mercury, and it didn’t disappoint me. I watched it glide slowly across the sun, and was transfixed by it until it ended. I cranked the power up as much as my PST would clearly handle to close in, and was surprised that it was a little fuzzy along some of its edge. I assume that it was from sunlight reflecting off the mountainous terrain, but I can’t help but wonder, with some hope, whether there was an element of a miniscule atmosphere boiling up. Since I missed first and second contact, I looked at my time keeper to see when third and fourth contact happened. I recorded third contact at approximately 2:38 PM, and fourth and final contact approximately 3.5 minutes later, just before 2:42 PM. I was tired, hot, and thirsty, but happy that I witnessed the event.

After resting awhile, cooling off, and having some dinner, I drove up to Salem, picked up Phil Driscoll, my observatory compatriot, and we headed to Salem State University to open Collins Observatory for the last public observing night of the season. It was almost surreal as we started off by viewing both the Moon and Jupiter while the Sun was still up. The Moon appeared rather interesting at that time. There was detail as expected on the Sunlit side, but we could see an amazing amount of detail on the unlit side of the Moon as well. It gets washed out by the light of the Moon at night. We then pointed the telescope at Jupiter, and I was pleasantly surprised at the detail that we could see in the cloud belts. There were lighter spots, wavy structures within the cloud belts, some irregularity visible at the edge of the two main cloud belts, and I wasn’t sure, but I believe that I could see the Great Red Spot faintly in the Sunlight. At that time, I wondered why more of us, myself included, don’t view Jupiter while the Sun is still up, especially when the Sun is low in the sky. As it got dark, Jupiter’s glare washed out some of the more subtle structure that I was seeing earlier in the cloud belts, and I forgot about the Great Red Spot, but there were more colors displayed in the cloud belts themselves. Jupiter’s other show after dark was the movement of the Galilean moons. It’s always fascinating to watch them moving around Jupiter and gliding past each other in the process. I often find it hard to tell which moons are farther from Jupiter, and Saturn for that matter.

We kept the observatory open until 11:50 PM to allow anyone that was interested a chance to see Mars and Saturn. During the time waiting for the planets to rise high enough to observe, we also viewed the binary stars Cor Caroli in Canes Venatici, along with Mizar and Alcor in Ursa Major, plus a few star clusters such as M44, M13, M3, and a few other objects. Both planets were well worth the wait. Mars was first, and early on I could make out minor color variations of what I believe were the highlands on Mars showing through the murk. Saturn was its usual self, with first three, then the four brightest moons showing, while still in the murk. At the very end of the night we paid another visit to Saturn and could see some of the more subtle variations in color of the different cloud belts, along with the rings that displayed the Cassini Division, as well as at least the four brightest moons which were clearly changing positions. There were probably several more moons visible, but we were anxious to move back to our last object, Mars, before we closed. By that time it was well clear of the murk, and we could definitely see more surface detail. If my memory and the maps were correct, I believe that we were looking at Isidis Planitia, and the high terrain of Libya Montes near the middle of the planet. Also, to my surprise, as I hadn’t considered the possibility at the time, we could see a tiny dot that looked like one of the Martian moons. I was happy with our possible good fortune, so I looked up the Phobos and Deimos positions when I arrived home. Taking into account the telescope design and the 90 degree diagonal, I determined that we had indeed seen Deimos. All in all, it was a wonderful day, and not too bad for a one eyed, gas bubble impaired astronomer with cataracts!

Respectfully Submitted,
Dennis Gudzevich

Photo credit: NASA

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