On bended knee . . . sometimes things just distract you.

On bended knee

Globular clusters fascinate me – partly because they play a Cheshire Cat-type game with the cosmologists. See one of the things cosmologists try to calculate is the age of the Universe. However, some studies of globular clusters have determined that they consists of very old stars – stars maybe as much as 15 billion years old. But as they look at other information about the universe, they come up with an ultimate age of the entire universe closer to 12 billion years. (Our Sun, for comparison, has been around about 5 billions years and is thought to be in mid-life. )

But you see the problem, I’m sure – how can you have clusters of stars that are older than the universe? So when I see a globular I feel I’m looking at the smile of some sort of very special cosmic Cheshire Cat – a smile that’s sort of doing a reverse fade – existing before the universe itself was born.

OK – this is all nonsense, of course. Something is wrong with one calculation or the other – and probably the calculation that is wrong is the one that says any given globular is 15 billions years old. At least, that’s what the scientific smart money says these days. But it doesn’t change the general impression of most globulars as ancient. These are, indeed, really unusual gatherings of stars in several ways and I was peering into the depths of three of them this morning, dubbed M53, M92, and M56 – all similar, yet quite different in appearance. (By the way – if your idea of a star cluster is the Pleiades, you need to understand globulars are very different. Where the Pleiades includes about 400 stars, a globular contains anywhere from 100,000 to maybe a million in a compact globe of stars. )

Despite all these stars packed closely together, M53 is just a faint, circle of light in the 8-inch LX90 with just a hint of graininess. Of course, that hint of graininess represents roughly 100,000 stars, their light shining from some 60,000 light years away. Does that impress you? It impresses me on one level, but I couldn’t get it to sound any deep chords. This was one of those mornings when I knew the tune, but it kept rolling past and would not sink in. When I switched to M92 I knew it was significantly larger and brighter – well, to our point of view, since it is also about half the distance away.

But the distance that was distracting me was the distance between me and the eyepieces of the binoviewer. I have two adjustable-height observing chairs in the observatory , but with M92 nearly directly overhead the eyepieces were very low and neither chair would go low enough for me to see in the eyepieces without uncomfortable contortions. I tried kneeling on the wood floor. I’m sure God chuckled to see me on my knees for a change, but it must have looked like I was worshiping the telescope and I was quickly reminded that I was too old to be comfortable for long that way. So I took a couple towels and folded them and that cushioned the impact some, but was still too low. Then I put a small box down and the towels on it. Right height, but not all that comfortable either. So I made a quick drawing and moved on to M56 which was lower in the sky. (That’s right, as you look at tings that are lower, the eyepieces come up.)

M56 is one I haven’t seen before and I almost didn’t see it when I first looked in the eyepieces. It’s faint and tends to blend into the Milky Way background – well, foreground really. (I am assuming that like most globulars, M56 is above or below the plane of the Milky Way, but in this case the angle must be such that we first look through the Milky Way to see it.) Back to the real issue - I had just had the red light on and been checking details about it in an observing book and a red light shining on white pages really does cut into your night vision significantly. That’s why I’m drawing, incidentally, on black paper using white pencils, The drawings aren’t better this way – may be a bit rougher – but my drawings are nothing to write home about anyways. Fortunately, I don’t care about – well, yes, I do – but I don’t care a lot about – the final product. The finished drawing really is not nearly as important as the process. Plain and simple when you draw you see things that you don’t see when you don’t draw. So I draw because it forces me to focus my attention and notice detail.

In this case what I noticed was how long it took for my eyes to dark adapt again – about three minutes – after using the red light on the white pages of a book. But having done that, the reality of this particular globular sank in just a tad more than the others had. See one of the facts I read was that this globular is about 10 light years across. Now the brightest star that we see see from the northern hemisphere is Sirius and it’s about 9 light years from us. Suddenly all the little synapses went off at once – 100,000 stars, jammed into a ball just 10 light years in diameter?! Hey – that must be like living inside a skyrocket when it explodes. Think about it – we see a handful of very bright stars in our sky at any given moment. Maybe a couple dozen of them are anywhere close to being in the league of Sirius – and Sirius appears so bright mainly because it is so close. So what would your sky look like if you had 100,000 stars that were all as close as Sirius or closer? I mean, there would be no night. (Isaac Asimov imagined this more than half a century ago and wrote a wonderful little short story called “Nightfall”first pulished in 1941. Read it some time, if you haven’t. Lots of fun.)

So that thought saved the morning for me, cool morning that it was. (I was wearing my scarf and winter coat and observing in the Observatory because there was a hefty breeze outside. Skies were wonderfully clear. Milky Way was bight. But all that wind would have shaken the 15-inch had I tried to use it. As it was, it shook the star images pretty badly. I didn’t even try to look at Jupiter and the Double Double could be split, but the pairs of close stars looked like they were continuously jumping across the gap into one another – fire licking at fire. Interesting – but not pleasing. This is what we call “bad seeing.” But the transparency was great. Dim stuff – like M53 and M56 got through. But on a steadier night I may have found it easier to notice the graininess that represented all those individual stars.

Bottom line – every night in the observatory is wonderful. Every night under the stars is wonderful. But some are more wonderful then others and it depends in a small way on the conditions outside me and beyond my control – but it depends more on the conditions inside me – and I don’t know who or what controls those most of the time. Maybe some day when I grow up I’ll figure it out ;-)