I am just returned from the driest place on the planet to a fairly ferocious winter storm dumping loads of water on Santiago. My students report via the group chat that their rides home have been very long. I had the opportunity to make a fool of myself by asking our Uber driver what the lights in the sky were. He clearly didn’t like us and he just glared at me and turned back to face the crowded streets.
It was lightning.
I will have much more to say about our program trip to the Atacama later. For now, I wanted to relate our astronomy exploits. I last discussed mixing astronomy and students here. The Atacama is famous for its skies. It is high and dry, existing in a rain shadow from the Andes to the east and coastal range to the west. San Pedro and its surroundings record over 300 clear nights per year. The dry, thin air makes it an excellent location for microwave astronomy as well as visual astronomy. Several world class observatories are located on Andean altiplanos. And amateurs, like me, come from all over to observe the southern sky.
You can also book “astronomy tours” at about half a dozen shops in town. Where Steve and I stayed, in April, is one such place. I’m biased as I know the owner of SpaceObs, Alain, is an astronomer and I have reason to believe that some of the other outfits are not stellar (ha! I crack myself up). The advertisement in town for SpaceObs, the place I stayed with Steve, is low key and to the point. Many of the others show photos that show objects in a way you will never see with the eye and a few put telescopes out in front of their shops that are “real” but very poorly maintained. I’ve heard other talk. If you have questions, let me know.
Suffice to say, I wanted to go to Alain’s place for a tour while visiting with my students. I opened it up to the students and virtually all of them wanted to go. Some didn’t want to pay the fee (20,000 pesos, about $30) and asked if I would take them out for my own tour the night before. If you know me, or if you’ve ever been under a dark sky with me, you know it can be hard to shut me up about astronomy, so, poor kids, the students got their wish.
I led a group of about 20 students down a dirt lane (they’re all dirt lanes in San Pedro) until the streetlights stopped…
One: San Pedro is much more brightly lit than I’d expect for a town that touts astrotourism so highly. It isn’t bad, per se, and the town is small. At SpaceObs, about six miles south of town, there is a minimal light dome but it is definitely there.
Two: In addition to my students, there were ten students from another fine American university with us in San Pedro. Many of these students joined us for the tours.
We ended up spending about an hour dodging cars and bikes and dogs as I gave a naked eye tour of the sky, tried to explain celestial mechanics, gritted my teeth through astrology questions and gave at least a dozen students their first look at the Milky Way.
Man, can you imagine being 20 and not having seen the Milky Way? Seriously, everyone, turn your damned lights out once in awhile.
I then passed around the binoculars and groups drifted back to the hotel, which was about half a mile away. The sky wasn’t that great and I couldn’t tell if it was being in town, high clouds or not being able to fully dark adapt. It may well have been all three. Still, it was far better than most students had seen.
The next night we, a group of 28, went to SpaceObs. It was farther from town than I remembered and well away from the lights of San Pedro. Alain gave a nice 45 minute introduction to the sky that was much better organized and delivered than mine the previous night. Fortunately, though, our run through the night before helped them answer questions he asked and, therefore, to look good. Always nice to have your students look good.
Alain’s naked eye tour was really outstanding. It covered a lot of ground in terms of how objects appear to move in the sky, nicely mixing humor, philosophy and everyday experience to both keep the students engaged and make his points. His green laser pointer was so much better than my beam flashlight (I was not able to find a green laser before leaving). He kept the students attention for almost an hour in cold weather after a heavy dinner.
We then moved to the telescopes and got lucky. SpaceObs has a pad with about eleven (I think that is what he said) scopes. Two, both 12-inch Meade Schmidt-Cassegrains, were trained on Jupiter and Saturn, respectively. A mix of SCTs and Dobs were pointed at various deep-sky objects and he had a nice variety, covering most of the types you can see in the sky.
First up was, amusingly to me, the Ring Nebula. The Ring is a beautiful, and prototypical, planetary nebula and is clearly a ring, a little ghostly donut, in the eyepiece. A planetary nebula is formed when a star sloughs off its outer layers in old age. The Ring is also quite far north, passing nearly exactly overhead in Winston-Salem. In other words, there is no reason to fly to Chile to see it. But, if you’re going to show astronomy neophytes a planetary nebula, it is the one to choose.
We also saw the Jewel Box (open cluster), Omega Centauri (globular cluster), the Lagoon and Eta Carina nebulae (emission nebula) and the Sombrero galaxy. Thus, he covered the major types of object. Several students, true to form, pissed me off by asking why the Lagoon was red. You see, we humans typically don’t see color at night, when we mostly rely on the rods in our eyes for vision. The rods are colorblind and give much poorer resolution than the cones which we use in bright light. That is why our vision at night returns greyish blurry images. You see fine at night if you adapt to the dark. But you don’t see as well as during the day. But younger eyes do often work well enough to show color on some objects through the scope. Both the Lagoon and Eta Carina nebulae were reported as red by students who had no idea to expect them to be so. It’s an accurate observation. And one that I, in my 40s, have no hope of replicating.
But the real treat was Saturn. Jupiter was impressive enough, though it was sinking low in the west. Two moons were nearly touching and some detail in the bands were visible. Saturn was at opposition the night we visited. That is, it was directly opposite the Sun as seen from Earth and, therefore, about as close as it will come during the course of the year. When we viewed it, it was 81 degrees above the horizon or only 9 degrees from zenith. Objects at zenith are seen through the least amount of air possible. Also, Saturn just went through its own solstice so its rings are as wide open as they ever get. The seeing was decent and we were observing at, I would guess, around 300x. The Cassini division was sharp and visible all the way around the planet. There was a definite dimming on the outer edge. There was a clear band with some mottling just above the rings. Including Titan, five satellites were visible. The students were amazed. A group of ten stayed outside even after Alain announced tea and hot chocolate would be served inside and retired there himself. I’ve seen Saturn thousands of times over my life and can clearly remember a dozen or so times. This certainly makes the list and may be the finest view I’ve had. Which was fortuitous, given I’d invited all my students to drop serious coin on the outing.
The moon rose over the Andes about a quarter to midnight and Alain got a scope aimed at it. Students quickly rotated through as we watched the silhouette of the mountains against the moon. Once it was up a few degrees, Alain helped one of the students snap a picture using her phone, which is shown below. She was wildly happy with it.
Once we were all inside and sipping hot liquids, Alain took questions and grew philosophical. He was quite open about his career, why he thinks it important to study the astronomy and how to use the stars to advance one’s dating life. Long past the time we were to have departed and as he was about to go into more detail on the last point, his wife came out and told him to let us go. We were sad to leave but quite happy and satisfied with the tour. I was thanked enthusiastically and sincerely for organizing and I caught several students the next day using the sky app he had shown them.
It was a great night and one I think we’ll all remember for a long time. The sight of the center of the Milky Way standing high in the east and the excitement displayed at the view and the views through the telescopes was very moving for me. On top of that, it confirmed, in my mind, two truths about sharing astronomy:
- Show newcomers Saturn. There is nothing in the sky as awe-inspiring and innately beautiful as Saturn. Additionally, despite them being “easy” to see, people are amazed that they’re real and visible.
- A clear, dark sky is unavoidably moving. Amateur astronomers complain frequently that the public seems to have “lost interest” in astronomy. Nothing is further from the truth. They have just lost access. Almost anyone will fall a little in love with the view if the sky conditions are favorable.
Okay, soon I’ll write up our other activities from the Atacama. And I’ll report on how many pairs of underwear I wound up with.