Free Public Programs Home | Driftway Observatory Home | Give You Joy Home

« Previous individual entry || Next individual entry »

Slithering Sea Serpents of Serenity


OK, I want to talk about those "serpents" eventually, but there's so much more I find pouring out as my observing experiences set off chains of mini-mind events. Observing is such a delight – and I'm so bloody lazy – that my experiences get way ahead of my reports of them. I want to try to be more consistent in reporting in this space, not because I think everyone out there really wants to hear all the details of what I'm up to, but because I think observing is a three-stage process:

  • Stage 1 – Prepare.
  • Stage 2 – Look.
  • Stage 3 – Reflect on your observing experience.

Sort of like the standard advice to someone preparing a speech – tell them what you are going to say, say it, then tell them what you said. It also works as an exercise to explore your own thinking and quite frequently I don't know what I'm thinking until my hands get to the keyboard. ;-)

That said, my idea of preparing for an observing session is an eclectic mix of the specific and general. I really don't want to do too much preparing because I'm afraid it will prejudice the experience – direct it in ways that I then miss some things. But there is absolutely no doubt in my mind, for example, that I am much better prepared to observe the moon having read – no, studied – "The Modern Moon: A Personal View" by Charles A. Wood. In fact, until I read this book I was more likely to curse the moon – as a nuisance drowning out more interesting things with its intense light – than observe it. Now I find myself really looking forward to the next opportunity to see our closest neighbor.

That's the mood – and the preparation – I brought to the eyepiece of the 8-inch LX90 November 21 when I knew a waning moon was high in the sky and was likely to give me an opportunity to study the general vicinity of the Sea of Serenity. I love these old names - Sea of Serenity indeed! The whole moon is more serene than our dustiest, most silent museum. Time – and change - is measured there in millions of years – billions really. What a difference from the hectic pace of our planet – and I'm not talking about the 5 pm traffic jams, or the recent rise of this brainy biped who is intentionally, or otherwise, constantly creating what we think of as monumental changes.

What I'm talking about is what we tend to see as the slow, majestic forces of nature – the running of rivers and blowing of the wind; a seed dropping in a crack in the rocks and ending up splitting giant boulders as it grows to be a tree; the moving of techtonic plates beneath our feet. These don't occur on the moon – at least as far as we know, or in anything remotely like what our planet experiences. So, for example, when we look at one of the craters on the moon there's a pretty good chance it was created during an intense bombardment period about 3.9 billion years ago. Large, moon shattering events, were frequent then - by my calculation about one every 117,000 years or so. Recently (meaning the last billion years) such events have slowed to a one-every-32 million-years pace.

But it boggles my mind to project myself back to any one of these instants in time when the moon suddenly shook from the impact of some giant piece of primal solar-system building material – think of it as a concrete block someone forgot to include in the foundation. It's zipping around in space, minding it's own business, until the moon gets in its way. Try to picture yourself standing nearby – at a safe distance, but just waiting. Think of waiting for 117,000 years (let alone 32 million) for something interesting to happen! And then when it happens you might have been on your coffee break, or potty break, or whatever and so missed it because these are not slow-moving events. Even the most unimaginably large events were probably over in a matter of minutes, or maybe days. But more typical would be literally "out of nowhere" a huge explosion would happen and a space the size of a small city would be blasted out of the moon and moon stuff sent hurtling – big stuff – for dozens of miles. And then silence and another 117,000 years, more-or-less, goes by with nothing of significance happening. Keep in mind, Jesus walked the Earth 2,000 years ago and our oldest historical records go back about 5,000 years and our Earth was dominated by Dinosaurs – with not even a hint of man to come – a mere 65 million years ago. That kind of time we can talk about glibly, but like huge distances, it utterly escapes our experiential knowledge – and yet, I find looking at the moon – really observing it – does bring me just a tad closer to an experiential knowledge of such time.

But back to the Sea of Serenity, just a wonderful place to be and when I attach the binoviewer to the LX 90 I feel like I'm on a silent helicopter flight just a few miles above the moon's surface. And I do mean silent. Of course I can't hear much anyways, but at 3 am, surrounded by the walls and dome of my tiny observatory, it's pretty silent for the Earth. Not moon silent, mind you, where there's no air to carry the sound waves, but Earth silent. And that's my preparation. No specific target, no real goals – just establish a distraction-free observing environment and be there and see what catches my fancy.

And what caught my fancy here was the discovery – for me, of course, not the world – that the Sea of Serenity has serpents! Well, at least on this particular moon day – let's see, according to the Starry Nights software the moon at this moment was 19.87 days old. That may seem like overdoing the precision, but one thing I learned during this session was how quickly the appearance of the moon changes – appearance, mind you, not the moon itself – with the changing angle of sunlight on any given feature. So, for example, if I'm going to see this area of the moon again even close to the way I saw it on this particular morning, then knowing exactly how old it was is important. Even next month at this exact stage in the lunar cycle – 19.87 days - these lighting conditions will not be precisely the same because of other variations in the Moon's orbit relative to us – but they'll be close and I'm too inexperienced an observer to know how close.

Looking at the whole visible portion of the moon to start with, what jumped out at me was how absolutely brilliant the crater Aristarchus is at this moment. We're talking gleaming-sequin-on-the-fabric-of-the-universe here, and I really do want to know why – why it should shine so much brighter than some other portion? Is the floor of Aristarchus a huge mirror? Briefly I tried to examine it more closely at higher power, but the atmosphere tonight is kind of sloppy and won't tolerate much above a magnification of about 187X. In fact, I used a combination that yields about 133X most of the time. So I back off that project - I'm pretty sure I'll find a satisfactory answer later in Wood's book – and move on to the less brilliant, but no less fascinating, Serpent in the Sea Serenity. (Doesn't that sound sinister? Poe loved playing with sounds that way. Hmmm... doesn't sound sinister to me, but then maybe I know I'm dealing with Puff the Magic Dragon here, or his kin.)

seaseerpent.jpgSee, this is the area right now where the line between light and dark is located, the sunset line – the so-called "terminator" - and that's the area that is most interesting. (Isn't it always so? Being in the middle of the ocean would bore me to tears – what's interesting is where two environments meet – where the ocean meets the shore – that's where all the action is. ) It's better here at the terminator because the sun is hitting at a low angle and stuff on the moon is casting long shadows and most lunar features are much more dramatic in this play of light and dark. So what catches my eye first is not a crater, but a long, serpentine wrinkle stretching roughly north-south across the whole eastern portion of Serenity. (I borrowed the photo at left from this Web site – but I could not discover who the photographer was – captures it nicely. )

No sharp, jagged peaks here – just a wrinkle. And that sends me to Antonin Rukl's splendid "Atlas of the Moon." (Another thing I like about lunar observing is my night vision isn't as critical, so while I use red light to search this atlas, it's pretty bright red light making the search easy.) What Rukl tells me is my sea serpent is a combination of "Dorsa Smirnov" (a system of sizable ridges about 130 km long) and Dorsa Lister (230 km) and Dorsum Nicol (50 km), (See why I don't study these things too much in advance? I'd rather see a sea serpent than a "dorsa" or even a "dorsum.") Again, atmospheric seeing conditions won't let me crank up the magnification enough to see the kind of detail in the ridges the atlas shows, but the system of ridges does lead my eye to two craters that roughly anchor either end – a huge, mangled one to the north, and a more pristine example to the south. Rukl tells me these are Posidonius (95 km with a "fractured floor") and Plinius (43 km), the one I think of as sort of the quintessential example of a lunar crater – textbook oval, with a sharp central peak and terraces.

For the next 45 minutes I focused on Posidonius. I couldn't decide if its general shape is a tadpole, or the letter "Q" – though the tale of the "Q" seems to bend the wrong way in my view of it. (The LX90 flips things left to right, so that's what I did with the photograph.) The sunlight is highlighting the "Q-tail" beautifully, and I assume it is a mountain ridge. However, studying the charts reveal it as part of Charcarnac, a 51km crater with "a disintegrated wall." In other words, it was a crater until something smashed it. Hmmmm . . . does this mean it was there first, then Posidonius rumbled into town, redrawing the surrounding moonscape? That's the heart of the matter, you know – not just observing, but asking why something is the way it is. Scientists have been doing this for centuries with the moon, constantly refining their vision, until now they have very plausible explanations of why things look the way they do – very, very plausible, but not certain.

Oh don't get me wrong – I don't have delusions about making any discoveries or any useful contribution in the smallest ways to lunar science – but this is a personal journal of discovery and that in itself is a goal worthy enough for me. My ultimate quest here is time – the most perplexing, if not the ultimate, mystery - and these silent moonscapes do help me experience it to a greater extent than normal.

On this particular morning what has really caught my attention about Posidonius is the way the eastern rim appears double. That is, there is a real bright, outer rim, catching the setting rays of the sun – and inside it a second rim, bright by normal standards, but not nearly as bright as the outer one. In the course of about 30 minutes I watched that second rim go from bright to dull, to nothing but three, widely-separated peaks that weren't all that well lit. Lunar sunset. That's a miniscule slice of real time illustrated by the interplay of light and shadow and thus calling itself to my attention. The picture above, taken by fellow Massachusetts amateur Edward Roach, and found on his Web site with many other terrific astro photos, gives some idea of what I saw. (I flipped this horizontally so it roughly mimics my view through the telescope.) But the photo shows details I didn't see, and, of course, is taken at a different time so while the sun is catching the outer eastern rim, the inner rim is not as brightly lit as it was when I first saw it.

But back to the moment and my state of mind during observing. What the heck am I looking at? A young crater perhaps? For once Mr. Wood leaves me frustrated. Posidonius gets one reference on page 81 in which he calls it "one of the most interesting features on the entire moon." Holy cow Chuck, give us a break. You gotta say more than that!

I suspect it is a young crater because the volcanic activity that came after the ancient bombardment did not fill up this crater and hide its inner mountains as it has done to some. (Wrong! Take a look again at Ed's picture and you will see lava has indeed flowed into this region. And when I checked Wood's book I did see Posidonius listed as belonging to the "Upper Imbrium" time frame. That means they think it was created between 3.2 and 3.75 billion years ago – after the terrible rain of stones referred to earlier – but soon enough to get inundated by lava which has not flowed much in the recent era. ) Bottom line – I have a lot to learn and I can't wait for another chance to study Posidonius – but I like this taking my knowledge in mind-sized bites. Maybe I'll actually remember some of this stuff ;-).

What's more, this Web site ( ) reports some fascinating studies and has some excellent photos taken through various filters that reveal more of the geology of the crater – though I need some one like Charles Wood to pull this kind of raw material together and tell me what it means in a larger context.

But there's more at work here than the scientific facts. The experience, in total, has an aesthetic side to it as well. There is a stark beauty – its been said before, but it certainly is true – to the moon. My field notes on this particular morning include: "This begs to be drawn." Or better yet, done in pen and ink with watercolor washes – not that I have the skill to do that – but what this and other moonscapes do for me is the same thing an Ansel Adams photo does – it gives me a new and deeper appreciation of tonal values, of the splendor of black and white with a million shades of grey and the magic of light. The world is complex enough and so loaded with information, that color can actually be a distraction sometimes. Maybe that's why they put the moon so close, kept it essentially in grey tones, and kept change to a minimum – so we humans, with our incredible ability to be aware of the universe, can take our first baby-steps to really perceiving it. And suddenly I get a picture of myself, flat on my back in the crib, staring up with glee at this pock-marked ball dangling above me – and making these almost intelligible gurgles and goos.

Posted by Greg Stone at November 22, 2005 06:27 PM Comments? Please email me:

Clear Sky Clock | Awe, awareness, and astronomy | Introduction to astronomy | Astronomy links | Driftway Observatory Home | Give You Joy Home