Observatory 1: Green Bank, part 2

Radio astronomy is a fascinating branch of science, in part because it is in some ways very different from optical astronomy. Since we can’t see radio, you can observe and gather your data anytime, day or night. The dishes that act as telescopes get basically one-pixel resolution. So where your phone or camera has several megapixels resolution, the largest radio dishes basically act as a single point, if I understand correctly. It is by panning the dish across an object that you are able to form a picture from it. But there is also a great deal to be learned from radio data without even making it into a picture. For example, different chemical elements give off unique radio frequency signatures. Hydrogen emits radio at 21 cm wavelength, which translates to a frequency of 1420.4 MHz. Since hydrogen is the most abundant element in the galaxy and the universe, you might think that trying to map it would be a little crazy. But an interesting thing happens when you observe a span around that 1420.4 MHz. Because of the nature of space and time and electromagnetic waves, we can detect if the hydrogen being observed is moving toward us or away from us, and how fast it is coming or going, and how far away it is from us. That’s a lot of information! So mapping the hydrogen in the galaxy is like making a navigational map of rivers, harbors, lakes, and seas. It gives you an idea in 3-D of how the galaxy is built and how it is moving and changing.

At the Green Bank Star Quest, I got to do some of that kind of science directly! After a workshop on the basics of radio astronomy (where I learned some of the above), we were given the opportunity to use the 20-meter dish to look at … anything we wanted! A couple others in the class and I looked at two significant radio sources, Cass-A (supernova remnant) and Orion-A (star-forming region). Later we added the Owl Nebula, the moon, Mercury, and a variety of other objects. Some were strong radio sources and others less so, and Mercury not at all, which is weird. I still have a lot to learn about what our scans mean, but it was amazing to be able to run a world-class instrument.

I also got to use the 40-foot radio dish at GBO. It is, I think, the smallest of the active dishes at GBO, but let me tell you, 40 feet is not a small dish! About seven of me end to end would fit across it. This dish is also rather historic in that, as I am led to understand, it was used by Frank Drake for the first SETI (search for extraterrestrial intelligence) experiments in the 1950s and 60s, Project Ozma. This is a transit dish, which means it is always pointed along the N-S meridian, rotating up and down but not side to side. There is a control room in a below ground bunker that looks like a science office from the 1960s. A couple stacks of electronic equipment stand in one corner, the instruments appearing to be of 1980s vintage. By means of analog dials and switches and a digital frequency selector and a tractor-feed data record with two pens, one can collect actual science data by aiming the telescope, selecting a frequency range, and interpreting the graph on the paper strip. It is wildly old school science, and it was a blast! Three of us worked together to get some data under the tutelage of our guide Sophie, but I got to take home the data. I followed some directions on a hand-out and found that the blob of hydrogen we investigated near the center of the galaxy was moving away from earth at (if I recall correctly, as I don’t have it here with me) 48 km/sec. How cool is that?

Along with experiences in several other lectures and workshops, I found that I was just having the best time being a science student again. It gave me a thrill, not only to be learning from professional scientists, but also to do actual science. To be transparent, I also got a thrill from being a good student, knowing or figuring answers to questions ahead of others in the class. Yes, I like being an overachieving, curve-busting, teacher’s pet and always have.

But really, it’s the thrill of the science.

Observatory 1: Green Bank

I spent four days and nights at the Green Bank Observatory (GBO) in Green Bank, WV, July 11-15. A local astronomy club has hosted the Green Bank Star Quest there for fifteen years. It is a very well run event, and I had a ball.

Now some star parties are just camping at a dark site, observing the sky at night and (as I’m told) either sleeping or drinking during the day. Not at GBSQ! First, there’s a bunk house and cafeteria, so no camping required, although you can if you want. Second, they had tours, speakers, and workshops lined up from 9am to 8pm every day, so no reason to be bored. These were really good, too! I learned so much about radio astronomy, “multiple messenger” astronomical discoveries (finding things out through various lines of inquiry), and even astronomy history! The evening keynote speakers were all very enthusiastic, interesting, and engaging on their various topics. I met some new friends as well as spending time with a college bud of mine. In fact, when I registered I was told I am now part of the Star Quest family!

There is more to write about this week’s experiences than I can manage tonight, but I want to get one thought out there. The principle scientist at GBO, Dr. Jay Lockman, was the keynote speaker for Thursday night. He spoke about his experience in developing one of the Great Courses for The Teaching Company on radio astronomy. He told us about the rather grueling process of writing, editing, and filming the course, about some of the history of radio astronomy that he learned himself in developing the class, and about his own radio research, which ironically ended up on the cutting room floor, all of which was quite interesting. His recent research is on the enormous bubbles of gas and dust that have been found to be expanding from the center of the Milky Way above and below the central core, and how, by tracking neutral hydrogen in those areas, some theories as to their nature and flow have been developed. This led my friend Bruce to ask in the Q&A, “As fascinating as this is, how do you answer those who say (and always there are those who say), ‘What is the point of all this? What difference does any of this make? How does this help anyone, or me in particular?'” Dr. Lockman asked Bruce what his answer is first, to which Bruce said, “My answer is, ‘What is the point of a baby?'” which I thought was insightful.

Dr. Lockman, acknowledged Bruce’s idea but went on to say, <paraphrase> “Of course we who do such things know about the intrinsic value of science and of any sort of knowledge, and we can talk about that and about how we may someday find practical applications to all these discoveries. Further, we can talk about the relatively tiny financial investment that we make in science and the vast returns we receive on that investment. But frankly, I am tired of trying to convince people of that. If it isn’t obvious, it is very difficult to get someone to understand it. What I have come to use as an answer instead is that people are interested in these things. I spend a great deal of my time telling conferences full of people like yourselves about this, and they are excited by it. We have 50,000 visitors a year that come through this facility, because they care about science and want to learn things. So it makes a difference because there are people who care about it.” </paraphrase>

This blew me away, and it continues to provide thought fodder for me. It is a great prophetic statement in its justification of something precious and its repudiation of the inherent repudiation in the question. Let’s look at other cases. We might ask, what is the point of professional sports? What good does it do anyone? What is the point of popular music? What is the point of photography, or sculpture, or quilting? What is the point of fishing, or hiking, or boating? What is the point of collecting antiques or beer cans or paperweights or dolls? None of these things has any practical justification, either, but people pour large amounts of time, money, and energy into all of them and more. People make careers around most if not all of these things, too. Why should science, which produces so much more value to the world than, say, football, be held up for scorn as a waste of time and money? And, if the value of science is found in that humans like it and find meaning and pleasure in it, then so, too, the value of all those other things as well, at least to the extent to which they are not harmful to human wellbeing.

Humans do what humans do. Some of us love science. Let’s give thanks for that.

Observing: 12 July 2018, Green Bank, WV

Observing last night was largely a bust. It was mostly cloudy until almost 23:00, after which it was patchy enough for binoculars. Just before midnight it really cleared, but many people had already retired for the night. I dilly-dallied until about 00:15, not trusting the sky to hold, but finally opened the scope. I got about 40 minutes in and the curtain slammed shut again. As predicted.

Nevertheless, I saw…

M55, a smallish-medium globular cluster SE of the Teapot in Sagittarius. Followed up with M28, another globular in Sagittarius, and a brief stop at Saturn. Didn’t spend much time on any of these and was feeling restless and tired. Sort of forcing it.

M31 Andromeda Galaxy was up, but pretty low in the sky still, but there I went. It appeared… oddly unimpressive at 62.5x, filling a good bit of the field of view (f.o.v.). Bright core, northern edge was well defined, or more than the southern edge, any way. Looked for M32 but had to actually use the GOTO to find it (embarrassing). Small, but bigger than stars, a fuzzy oval.

While I was focusing on the NE sky, the SW was clouding over again, and by 00:55 most of the sky was gone. I did attempt M15, a globular in Pegasus, but to no avail. The evening was done.

Bruce and I did see an IRIDIUM flare while he was scanning with his binocs. It was in the SE at about 40º elevation (?) around … 22:30 – 23:00 – not sure; forgot to check the time. It was super bright, ramping up, FLASH!, and ramping down all in about one second. It’s the second one I’ve ever seen, I think.

Observing: 11 July 2018, Green Bank, WV

Last night Bruce, his friend Paul, and I set up scopes near the parking lot while most folks were on the observing field. It was mostly dark by 22:00, but much cloud. It started breaking up, and by 22:45 was almost entirely clear and GORGEOUS! Really dark, transparent, and surprisingly steady. My Celestron 8″ Nexstar Evolution performed beautifully, especially considering I aligned on objects that were still popping in and out of cloud. Mostly used the 32mm eyepiece (e.p.) (62.5x), which showed off several deep space objects (DSOs) really well. For planets, I pushed to either 25mm (80x) or 15mm (133.3x), but not much more than that. Saw four planets – Venus (1/2 phase), Jupiter, Saturn, and Mars – but didn’t spend much time with them.

Venus was in and out of clouds and set soon, so just glimpsed it.

Mars was a blob, maybe with some polar cap, but nothing to write about.

Jupiter, with a neutral density filter to cut the glare, was pretty, and the Great Red Spot was visible about half way from the meridian to the east limb. Not much else visible but a few gray protuberances on the NEB (northern equatorial belt).

Saturn is what it was the other night: rings open, disk overlaps halfway. No evident shadows. Temperate zone to pole (N) shows darker color than below. It was pretty but the seeing was pretty wobbly.

Saw several nebulae of different sorts and also globular clusters and such.

M27  Dumbbell Nebula (planetary neb): large, obvious, sort of boxy, fuzzy thing; brighter on W side than E. Or is it maybe N than S? Edges indistinct.

M39 Open cluster N of Deneb: couple dozen stars. Nice.

Veil Nebula (supernova remnant): faint vertical stripe across star field, kind of like a wrinkle across space.

M11 Wild Duck Cluster (open cluster): almost like a globular! Really beautiful. Looks a lot like…

M22 (globular cluster) in Sagittarius: large, bright, evenly grainy.

M29 (globular): small glob, also in Sagittarius. Bright core with scattered stars around the edges.

M69 (globular): pretty much the same as M29

M6 Butterfly Cluster (open cluster): big, bright, about 3 dozen stars

M7 Jewel Box Cluster (open cluster): much the same as M6.

M8 Lagoon Nebula: looked great w/ SkyGlow light pollution filter! Really helped the contrast, even with pretty dark skies. Dust lanes and nebulosity stand out more.

M20 Triffid Neb: also great w/ filter. Could see dust lanes!

M17 Swan Neb: beautiful w/ filter. Appears upside down with feathery “body” at top, then the arch of the “neck” with two stars upon it. Can’t make out the “bill” so much at this mag.

Then at 01:00-01:15 it went from clear to covered! Clouds smoothly closed the show.

Got to bed @ 01:30. Woke up at 06:30 and couldn’t get back to sleep, so up and showered at 07:00 or so. Which is pressing me toward a nap, now that it’s afternoon.

This is a great first stop for the sabbatical tour!