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]]>1. Why do I love double stars so?
2. And why do I love this little 80mm Orion Eon telescope so much more than it's larger cousin, the 100mm Orion ED ?
I think the second question is a bit easier, so I'll tackle it first. It has nothing to do with optical quality. Both yield pristine images. But mechanical quality and sheer good looks? The Eon has the 100 ED beat by a mile. The Eon looks like an Alpha Romeo next to the 100 ED's work-a-day, American Motors appearance.
Yikes! I hate myself for saying that! I can hardly believe I would write such a thing. I am the guy who would always defend the hard-working, no frills, spare-me-the-lipstick approach. Yet I have to admit I have three small refractors - the other is an Astro-Tech 66 - and of the three the 80mm Eon is my first choice, edging out the Astro-Tech 66 only because it gathers a bit more light. The practical part of me will choose the 100 ED when I think the objects I want to see are a bit too challenging for the smaller scopes - but when I do, the romance goes out of the experience.
But there's something else at work here and I think it has to do with relationships. See, me and the 100 ED got off to a bad start because in purchasing it - used on AstroMart - I did so against my better judgment. I was going for simplicity and optical quality, but the previous owner had added a motorized focuser to the scope which he insisted I would love. I was definitely in KISS mode, but I let his sales pitch get the better of me and bought it. Well, the auto focus never worked. I don't think the owner lied. I simply think it got damaged in transit, though that wasn't obvious to me at first. But it set up some bad blood that I started taking out on the scope. Unfair? Of course. But relationships are complex things. That was more than a year ago and despite the wonderful images delivered by the 100 ED, I simply can't warm up to it.
And I admit - the polished mechancal slickness - with mechancal fine focusing - of the other two scopes appeals to me. The fine focusing part is logical - but I never thought I'd care about the finish on a telescope tube. Hey - the whole idea is to use a scope in the DARK. What's important is not what the scope looks like, but what it is like to look through - what sort of images it delivers.
And about those images - they're terrific. Especially with planets, the moon, and double stars - although where I notice them most is with double stars. Planets and the moon still don't excite me that much - too familiar, too close to home. Galaxies are fun, but they're so far away, so faint, so huge that the numbers defy any attempt at comprehension. Star clusters are great - but again, the numbers tend to overwhelm.
But turn the scope towards Castor and I find something my little mind can manage - barely. i did that this morning after first spending some time with the last quarter moon. I had the 80mm Eon in the Observatory mounted on the "go to" mount that's meant for the Celestron 8 SE. A simple "solar system align" had put me in business quickly and the moon was right smack in the middle of Gemini, so asking the computer with this ridiculously simple , one-object alignment to find Castor was no stretch. It did and tracking was good and steady.
Castor split easily at about 75 power, but I was really much happier with the 175X view provided by a Hyperion 3.5mm eyepiece. What it shows you is three stars - two bright ones very close together and a third member of the system that is much fainter and well off to one side. I've seen it many times, but I never tire of the view and I think the reason is that in a universe where the size and distance of things so often overwhelms us, Castor is much easier to contemplate and begin to grasp.
I say "begin" because Castor is really six stars. We see one with the naked eye - three in the telescope - but each of these stars has a hidden companion, detectable by spectroscope. Frankly, I don't dwell on that. What I do in my meditative moments, however, is try to imagine myself on a spacecraft - or planet, near one of these Suns and how my sky might look from such a vantage point.
And this whole complex system is but 50 light years away - so the light I'm seeing now left Castor when I was about 17. That's manageable. I can almost imagine being 17. Much easier than trying to grasp the view of the Andromeda Galaxy I had the other night. Never mind that the light from that object had been travelling more than 2 million years to get here - as I looked at the galaxy I knew the light from one side of it had left those stars about 150,000 years before the light reaching me from the other side of it. I can write that sentence. But 150,000 years is way beyond my experiential understanding - let alone the 36 million years for the journey from another galaxy I was viewing earlier that same evening.
So I come back to my doubles, sip my tea, and meditate. And after spending about half an hour with Castor et al, I realize that another old favorite, Rigel, is now in view. (See, I have to wait for the trees to move and for Rigel to come into my due-south gap. ) At this point the sky was getting lighter in the east and that might actually have helped me split this challenging star. Rigel is big and bright. To our eyes, about as bright as Castor - but the light from Rigel started it's journey to Driftway Observatory roughly around the time the nobles were holding John's toes to the fire until he signed the Magna Carter. That's a mental construct for me - not an experience. But hey - 800 years, i can extrapolate from experience and have some grasp that. (Ok - you ant to get technical. The Hipparcos' “best guess” for Rige;s distance is 773 light-years ), with a margin of error of about 19%.)
But it's just plain fun to be able to "split" this double because there is such a large difference in brightness that the faint companion star gets lost in the glare of Rigel. The companion is almost bright enough tobe visible to thenaked eye if it were off by itself somewhere - but that still puts it more than 500 times fainter than Rigel!)
And speaking of that glare - no, I can't really come to grips with the idea of a star that is 40,000 times as bright as our Sun. Hmmmmm.... wonder how far away the Earth would be to make it habitable if it were orbiting Rigel? And how long would an orbit take? How long would a single year be? But you see - those sorts of questions are within my grasp. I can play with them.
But aside fom this rational approach, there is just the simple aesthetic beauty of the two stars, close together - and the closeness invites easy and subtle comparisons of brightness and color.
And in the final analysis, my relationship with double stars probably is no more rational than my relationships with different observing instruments. i just know I love 'em.
]]>I counted nineteen bright ones this morning – three before I even got my pants on – and this was about a full day after the predicted peak of the shower. Slept in, did you? Oh ye of little faith! Of course, I would have preferred to do my Perseids watching on Tuesday morning. That’s when the shower was supposed to be at its maximum. But this morning was just about as good for me as last year’s maximum. That certainly drove home the point others have made - that it’s well worth looking for the Perseids at least a day before and day after – well, a night before and night after – the predicted peak. In fact, I saw a few stray shower members during morning observing sessions a week or more ago – but that’s pure luck.
I didn’t invite anyone out for this morning’s show for two reasons. First, the weather forecast was still iffy. The Clear Sky Clock had the sky free of clouds, but the transparency very poor for the best viewing time – between 2 am and 4 am. And besides, even if it was clear I wasn’t that confident the shower would be this could on the morning after.
I should stress, too, that mornings are the key for one obvious reason – that’s when the shower’s apparent radiant – the point in the sky where the meteors appear to be entering and fanning out from – is high up in the northeast. Look at some reasonable (from human stand points) viewing time such as 9 pm and you’re cutting off about half of the possible meteors you could see.
Still, on Tuesday night I did get up about 3 am and I did look out the upstairs deck door and I did see bright flashes in the sky – flashes of lightning. We went on to have about an hour of one of the worst thunder storms in recent years - at least for Driftway Observatory. This morning my viewing plans were much more casual. As I say, the Clear Sky Clock had not been encouraging, indicating these couple of prime hours would not be so prime. So still half asleep and sweat pants and sweat shirt in hand, I stepped out on the upstairs deck about 2:05 am and said to myself – yes – transparency is pretty horrible. Then bingo – there’s a bright Perseid, burning a trial through the murk towards the Pleiades. Wow! Not bad. Probably the only one I would see.
I looked around. Yep. Conditions are terrible. I can see just three stars in the Little Dipper. About the dimmest star I can see was third magnitude. Whiz! There’s goes a second bright Perseid. I kept looking up. Zing – that makes three – and in less than five minutes. That’s pretty good. I put on my pants and sweat shirt, sat down in a damp chair and sure enough,. here’s a fourth. This is a real shower, I thought. But the fifth one was a long time coming and I finally broke my gaze long enough to put on my socks. Now it starts to look like the Clear Sky Clock was off a bit. In just 10 minutes – about two hours ahead of schedule – the transparency is improving. (OK – my night vision might have been improving a bit too, but usually it’s pretty good right away when I’ve been sleeping in a dark room.
I stayed out for about twenty minutes and came away with five Perseids. Not bad. Time to make some tea, get a coat, and head for the Observing Deck where I have a proper – and dry - rotating beach chair that allows me to back comfortably. Besides, if it were really clearing, I could do some prowling around familiar objects such as M31 with the 15-inch.
So I did that. I uncovered the big scope, grabbed my best eyepieces, and prowled about. The Telrad was pretty foggy, but with the 22mm Nagler in place I had a fairly large field of view, so it wasn’t much trouble to find the Double Cluster and the Andromeda Galaxy. Actually, I stumbled across it’s companion. M32. first. But the view just convinced me that I really prefer the view I had last week in a small refractor. Mind you, M32 and M110 are much more impressive in the 15-inch, but to get the full emotional impact of M31 you need a really wide field. It was more appealing to me this morning as seen in the 12X36 IS Canon’s – really. On a whim I pointed the 15-inch low in the northwestern sky – my most light-polluted quadrant - and looked for the Double Double. Again, I prefer the view in the smaller refractor. Oh, it split comfortably in the 15-inch – especially with the 7mm Nagler (about 241X) and to split it at all when it is this low in the sky is good. But the view was, in a word, sloppy. I’ve just gotten hooked on the pristine, high-contrast images of a good, small refractor.
As I aimed the scope at the Double Double, however, I did see another Perseid. This was number 7 and a real beauty, streaking down towards Lyra. And it made the point that Perseids can appear anywhere in the sky. Yes, they appear to radiate from one point – but their trails go back towards the radiant – doesn’t means they reach anywhere near it – just that they point in that direction. So figure if I saw 19 bright Perseids – and maybe glimpsed a half dozen others – that what I actually saw was probably less than half of what was visible during the time I was looking. That is, I can really see at most about one quarter of the sky at any given instant and some of that is blocked by trees, bushes, telescope, fence, etc. Also, I had perhaps a solid hour of seriously looking up – though I didn’t time myself. I doubt it was much more than that – so 19 bright meteors in an hour means one every few minutes. Of course they don’t arrive like that. They seem to come in burst with long periods of nothing.
Nothing can try your patience, but the “nothing” this morning included a Milky Way that stretched from Cygnus, low in the Northwest, to Orion rising in the Southeast. That gave a great sense of the plane of our galaxy, certainly worth contemplating any time. Quite a jump there, really, when you think about it.
Let’s see – we have Andromeda and friends beaming in from roughly 3 million light years. (The distance is still disputed.) Then we have the edges of our own galaxy mapped out in the Milky Way. And in an around it I roamed about with the 12X36 binoculars, pausing at the Double Cluster in Perseus, as mentioned, but also the familiar trio in Auriga – M37, 36 and 38 – all easily picked up,as was the fog of billions of stars in another nearby galaxy, M33. The clusters range from roughly 2,000 to 8,000 light years away. Closer to home were the familiar Pleiades at 400 light years – and always demanding some of my observing time. And then, through the branches of the mimosa I could see the Hyades with their “house” asterism, rising from just 150 light years away.
But the real show was much closer and several bright streaks brought out involuntary oohs and ahhs that I shared with the owls, rabbits, and other night creatures. There was a great one – number 15 I think – that stuttered it’s way towards the Hyades and seemed to be the slowest of the night. And the brightest – about magnitude -2 – was over near the northern horizon, well below the Little Dipper. And distance?
Well, these tiny visitors from outer space were pebbles at best – about the size of an eraser on the end of a pencil. Mull that over a bit. Not much. Certainly not what we’re used to contemplating in terms of astronomical objects. And what I could see of them was taking place pretty locally = perhaps 50 miles over my head.
Yet these tiny visitors from outer space were roaring in om us and running smack into air molecules in our upper atmosphere and those collisions were so violent that they parts of them started to ionize and emit light waves that were so bright I could see them outshining the stars, though they were 50 miles away. I mean, what do you think your flashlight would look like from 50 miles?
I know some folks are fond of miracles. They keep looking for a break in the natural laws. I consider the natural laws the miracle – and when I really think about what it means to see a meteor – what you are actually witnessing in that streak of light – well, a few ooos and ahhhs just don’t do it justice!
I was remembering last fall and how great it was to see Comet Holmes drifting, night after night, in the star fields around Mirfak.
Then I concentrated on the comet, long since faded from sight, now, with the 22mm Nagler I focused on those wonderful star fields it passed through. What an incredibly rich area! Then I recalled one of my favorite open clusters, M34, the "Klingon Warship" - at least in my mind - and without making any serious attempt to find it I started prowling in what I thought was the right general direction.
But my directions were off. When I thought I was meandering towards Algol, I was really meandering towards Capella and on a line about halfway between Capella and Mirfak I discovered a wonderful open cluster. The main stars on one side formed a distinctive "J" and I took a notepad and began to make a rough sketch of the cluster. I won't share that sketch. I will only say it was good enough so that when the morning twilight finally drove me in, I could easily identify this little gem - it was NGC 1528.
My point here is that while I generally prepare for an observing session, learning in advance about what I plan to observe, I also like to go the other direction. It is great fun, especially when using a small refractor under manual control,to simply prowl about, discover somethng interesting, make reasonable notes, then check the charts and books to learn what you have discovered. That's something I suspect many of today's amateurs miss because they become wedded to - too dependent upon - their computerized "go-to" scopes. Oh I'm not going to quibble about using a computer and "go to" - I do it frequently. But a lot of times I find it gets in my way. It just adds complexity and contributes to the general atmosphere of haste - a sort of "it's Tuesday, so this must be Copenhagen" mentality.
With the small scope and smooth, manual controls on an alt-azimouth mount I generally have a more deeply productive observing session. And sometimes I even make my own "discoveries." Such was the case this morning.
Oh - here's a nice picture of it - but this isn't what I saw. The camera goes much deeper than my scope, shwing many more fainter stars and making the distinctive "J" pattern of the bright stars on one side of the cluster harder to detect.
]]>. . . and this morning it was Double Cluster time. Oh my! And one quick Perseid, in for an early appearance. And space junk galore because at this time of year we're not that far from sunrise when the Double Cluster is high and sparkling in the northeast. Another morning - another round with the 80mm EON, anbd 22mm and 7mm Naglers, sandwiching the unbeatable 13mm Ethos - more indellible memories. Time - it takes time, and a balnk mind, and clear skies.
]]>That's what I felt this morning and it's been a long time -maybe a year, maybe never- since I had such an experience - felt quite this way. The trigger was the Great Andromeda Galaxy and its roadshow groupies, M32 and M110. Never can I remember seeing them quite so well. Oh I had all the right tools! Luckily my Meade LX-90 had blown a gasket again and was awaiting repair. That means I was going the minimalists route in the Observatory - well, minimalists in dimensions, not in quality. I had mounted the new Orion 80mm Eon refractor there, a sleek piece of mechanics holding beautiful optics - and it rode on the head from the AstroTech Voyager, my favorite alt-az mount - smooth as butter (when the cliche fits, use it! ) - and with those large, easy-to-find-in-the-dark, slow motion knobs. For eyepices I was going from 22mm to 13mm to 7mm Naglers, with the real crown jewel, the 13mm Televue Ethos, as the dominant centerpiece.
What this gave me was an ideal set of tools to reach across a couple million lights years and pull in a few hundred billion stars. All I needed was the soul to grab and hold them and miracle of miracles, it was there! I kid you not. The tools are nothing, unless you also bring to the show a modicum of experience and skills, and huge helpings of spirit. What spirit? I don't know. The spirit I seek in my "Silence Under the Stars" sessions - the spirit I don't know how to teach because I don't know how to summon it myself. But i know it when it's there.
I know it grows - for me - out of meditative practices, with the emphasis on the word "practice. "It's not that viewing a distant galaxy requires meditation - meditation is about practicing - it's about exercising those parts of your brain so the paths are there, open, and easy to slide down when you need them - like when you're working in the yard on a blue-sky, friendly-cumulus-cloud day, and you look up to see a pair of ruby-throated humming birds, working the feathery blossom of the mimosa tree and you know there's no proper response but to drop your rake, fold your hands together before you, and bow silently with the deepest respect.
And that's how it was at Driftway Observatory this morning as I carefully set my tea on the small ladder I use to open the the shutter in the dome, arranged the observing chair to the right height, and took my place behind the Eon with the 22mm Nagler showing me a huge swatch of universe and there, despite my lack of dark adaption, was not simply the familiar blur of the Andromeda galaxy, but the tiny fuzziness of it's companion galaxy, M32 and the elusive puff of smoke that is yet another companion galaxy, M110 - and I could trace the ghostly spiral arms of M31 - the main show - out to the extremes provided by this gorgeous, wide-angle eyepiece and I was there . . .
Where? I don't know. Out at M31. On my chair. Looking into a crisp sky that barely eight hours before had held a gorgeous double rainbow Bren and I had admired from the upper deck. Astronomers would give the transparency of theis morning sky "5"- with my mind set of the moment it was off the scale. Can I show you these things if you've never seen them before? I hope so. But it's not only chance that favors the prepared mind - the universe demands it. You prepare and nothing happens. You prepar emore and nothing happens. you have faith and keep preparing - and one day - one night , you get taken by suprise . . . Oh I hadn't done any specific preparation this morning. I had gotten up, nuked a cup of Earl Grey tea in the microwave, found a light jacket -my flashlight and keys - and headed out for the observatory. See, as I rolled out of bed I could see blackness out the door to the deck - a good sign, and as I walked over there, there were the Pleiades, glistening like Tennyson's "swarm of fireflies," and north of them my old friend, Capella. That's what had beckoned me out.
Having no distractions in setting up helps. Close the observatory door behind you, turn on the red light, take the lens cover off the scope - climb the small ladder and open the shutter - maybe three minutes - maybe five, and I was observing. No computers. No video. No hassle - none, well, a bit of pain. Andromeda was high overhead and my shoulder, back, and right arm have been under attack lately from muscle strain, or arthritis, or maybe just being 67. . . anyway, it's rather painful to look straight up and try to sight along the scope, but that's a small price to pay for the results. I think I spent an hour with Andromeda. I don't know for sure - it flew by. I knew we were getting into astronomical twilight and before I lost such a dark sky, I took a quick look at M33 - easily visible in the finder and perhaps to the naked eye - as well as the double cluster in Perseus and, of course, the Pleiades.
I experimented a little. I determined that there wasn't much difference between the the 82-degree apparent field of the old 13mm Nagler and the 100-degree apparent field of the new Ethos - not much except one costs around $300 and the other about $600. Was I an idiot to pay $600 for an eyepiece that gives just a modicum of improvement? Of course not. It's an improvement and at my age I need every edge I can get. "Need" - no - I'm sorry. That's not the right word. I hedge my bets by using the best I can afford. I don't think any of this was necessary for the experience I sought and had - not the fancy eyepiece, nor the fancy telescope, nor the observatory. Those aren't the crucial ingredients. The crucial ingredients are in you - or in this case, me. You're pinging your synapses with light that's two million years old - or maybe three. Your're looking at a galaxy that fills your eyepiece and the light reaching one edge of that eyepiece took 150,000 more years to reach you than thel ight that fills the other edge. You need to knw these things - or I do. There's an element of linear thinking here that's important. But it's not the crucial part of the dynamic.
The crucial part emerges for me from the meditation. It's missing when I have been too busy. It' s missing when I'm starting my day by reading the latest salvos on 'the campaign," or turning over in my mind the weird "facts" in the case of the anthrax killer - or suspect - or whatever. In short, the monkey brain has to know stuff, but it has to know the right stuff - and then it has to be put on hold and it has to let the galaxy rush in and it can't be messing with the details of a computer control, or even the fine difference between the 13mm Nagler and the 13mm Ethos and isn't it amazing that you can see all this wth a telescope no longer than your arm, and a lens the size of the saucer under your tea cup?
No - the mechanics aren't important - the image and gestalt is - and that's what stays with you and if you're lucky you end up, as i have, with indelible images burned on your brain and spirit. I once knew the distance to Andromeda. I knew it on just such an early morning as this, half a lifetime ago, standing on a small hill, using another small telescope, and being scared out of my wits as some neighbor's dog howled - and me with my head a few million light years away!
This wasn't a repeat performance - life doesn't repeat itself. We have one-time experiences. But on a scale of 1-10, this was a 25 - a resounding "welcome back" from Andromeda. I don't know where I've been lately, but I know where I am and it's where I want to be.
The above image of Saturn - complete with Cassini Division (a difficult target now) and the shadow of the planet on the rings, was taken by Steen Weichel and sent to me today with the following note. I think it's a great illustration of what you can do with this little scope. (Use the search box on the right of this page to search on "66" and you'll find several reference to my own observation with the Astro-Tech 66.)
Hi,
Thanks for posting the review, very interesting. I got myself an AT66 at the NEAF in New York this year and thought I would share an image of Saturn I made with it. Notice that cassini is visible, i think its a very good little scope :).
Its stacks from a toucam processed with registax.
Best regards,
Steen Weichel]]>
Put me on a lonely island with a dozen telescopes and one eyepiece and I want that eyepiece to be the 13mm Televue Ethos.But give me five eyepieces, and I would choose 24, 13, 8, 5, and 3.5mm Hyperions from Baader Planetarium.
My point - the Ethos is wonderful and I will reach for it first in almost every situation. But the Hyperions are great and I could buy five of them for about the same - or at sale prices, less - than the $620 price tag of the Ethos.
I compared the 13mm Ethos with it's 100 degree apparent field of view and the 13mm Hyperion with its 68-degree apparent field of view in three different scopes - an 8-inch SCT (Meade LX90) , a 15-inch Obsession, and a 4-inch Orion 100ED. In each case the Ethos was better in contrast, edge-to-edge sharpness, and - of course - providing a sense of context with that large field. But did I actually see more detail with the Ethos? Maybe. The three objects that gave me this feeling were M11 ( Wild Duck Cluster), M27 (Dumbell) and the Double Double in Lyra.
In the Wild Duck Cluster I felt I could see a tight grouping of faint stars near its core better in the Ethos. But when it came down to actually trying to count them, I wasn't so sure that the Ethos was doing better. With M27 in the 8-inch i was sure I could make out the brightness difference of the two halves better with the Ethos. And with the Double Double - on two different mornings - I found it just on the edge being cleanly split with a 13mm eyepiece - one morning using the 8-inch and the next the 15-inch. Ibn both cases I could get a clean split on at least one of the pairs with the Ethos and I could not do this with the Hyperion - close, but no black sky! (In the 15-inch this morning both pairs split inthe Ethos - niether inthe Hyperion. ) 
But in all cases I had to look hard to see these differences.
Bottom line: I would purchase a set of Hyperions before buying the Ethos. (Actually, i think my choices would be the 24, 13, 5 and the 8-24 zoom.)
I certainly don't regret purchasing the Ethos. There's something to be said for going with the best and this is the best. I still need to see how well it does in the Barlow, but even without that as a fall back, it is a great, all-purpose, any-scope, eyepiece. But I could live without it. The Hyperions are nice, reasonably priced, alternatives and they've been my main eyepieces for the past year.
One complaint - the Ethps os heavy and with small scopes requires rebalancing when I switch to other eyepieces, such as the Hyperions - and the Hyperions are not exactly light weights.
]]>Anyway, the story Don was talking about can be read here. That story inspired Dom to respond from Australia:
Pity he shifted his observatory to Flagstaff -- that monster telescope, if still around, would be a magnificent sight. Of course, it real terms of viewing the universe, Driftway Observatory is a thousand times better.
And I responded:
Ahhhh . . .how I wish it were. I appreciate the vote of confidence, but Lowell has me beat. The 25-inch Clark is alive and well and is not only in use, but as with Driftway Observatory, Lowell's main function today is public outreach and they do far, far more than I have ever dreamed. The only advantage I have is mine is here and I can be using it on five minute's notice ;-) . In fact, for a mere $150 you can reserve Lowell Observatory for an hour and a half. See:]]>http://www.lowell.edu/outreach/hours.php
A 25-inch refractor will put anything I own to shame, and Arizona skies are darker and clearer, though I suspect civilization has encroached on this observatory and they may have a problem with light pollution.
But Lowell is one of the most fascinating of characters. This was an excellent account and I'm glad they tied it to the current mission which I think is not getting the attention it deserves. This really could be the breakthrough as far as discovering life elsewhere is concerned and if they do, this will be the most important event of our lives, for I think this question of life elsewhere is getting stickier and stickier. It used to be such a sure thing - with all those stars there must be life. But the more we learn the less sure it has become. We assumed such a discovery - in fact, an encounter of the third kid - was just a matter of time - but there is more and more evidence that life is rare and intelligent life exceedingly rare - all of that, however, could change with what happens on Mars in the coming weeks. They won't find intelligent life, of course, but hard evidence of any sort of life would be a major find. You can follow the mission at this Web site:
http://phoenix.lpl.arizona.edu/
Now that said, I was surprised that there was no mention in this article of Lowell's 1907 mission to Chile. Lowell didn't go personally, but he sponsored the mission by an Amherst astronomer who took an 18-inch (several tons) refractor there and set it up in the high dessert and came back with 13,000 photographs of Mars that were the talk of the day. The whole objective was to take advantage of an especially close approach of Mars from an ideal location. (no rain - the telescope was set up for months in the open - and very clear, very steady skies with Mars almost directly overhead. As perfect as you can get on earth.) We get to observe Mars closely for only a few months every two years and some approaches are much closer than others. Lowell sponsored this because he was sure the photographs would prove his visual observations were true and the Wall Street Journal, among others, felt he had succeeded. In 1907 that distinguished paper wrote that this was the most important story of the year 1907 - not the current financial panic, but " . . . the proof afforded by astronomical observations . . . conscious, intelligent, human life exists upon Mars." Visual observations from Chile, telegraphed to Lowell, had everyone in the expedition seeing the canals clearly and poor Lowell was chomping at th ebit for the photographs and in absolute ecstasy at these reports.
Today is you look at the tiny images - Mars measures just 5mm across on them - seeing evidence of life is like reading tea leaves. Those who thought the canals were real, such as Lowell, felt the photographs proved it. Others, with less-prejudiced eyes, could see no such evidence. (I've seen the images reproduced and they are wonderful, especially for the technology of the day, but I certainly can NOT see any sign of canals. )
This whole expedition was a sad cap to Lowell's Mars efforts. He battled with Todd, the leader of the expedition, over who owned the photographs which were actually taken by another person. After this effort Lowell shifted his emphasis to finding Planet X - Pluto - and after his death Pluto was indeed found by Lowell Observatory,as this article notes. I'm afraid, however, that it really does deserve it's demotion - it is real two bodies and they are two of many and Pluto isn't even the largest of such objects discovered. Still, it's interesting to note the emotional attachment people have for "lonely, little Pluto" as the ninth planet.
If you'll permit me a minor technical side note - Lowell came into this at the end of the age of giant refracting telescopes. The truth is, any refractor bigger than about 15-inches in diameter starts to seriously work against itself. The object of any telescope is to gather light - but as you make lenses larger and larger, you also have to make them thicker, or they can't hold their shape - and as you make them thicker, they absorb more and more of the light that passes through them. The largest ever built was 40-inches, but a reflector of the same size would significantly out perform it since the light doesn't pass through a reflector. My 15-inch is a reflector - add the video camera to it, and put it side-by-side with the Lowell 25-inch and I suspect my "little" scope would give the 25-inch monster a run for the money. But . . I love the idea of looking through that telescope. Just sitting behind something like that and looking up at the sky . . . well, it's almost exciting enough to get me to travel to Arizona ;-)
Well, not just exit pupil, but of the various numbers associated with eyepieces the exit pupil is a good way to set one limit. My new 'Ethos' arrived - the most expensive eyepiece I ever dreamed of purchasing - and that's what really got me to thinking about how to best use it in various scopes and developing a whole new strategy both for telescope use and mixing and matching eyepieces.
What I want in an eyepiece - and I suspect most of us want - is the widest field obtainable at the highest powers usable without sacrificing quality and that's where the Televue 'Ethos' comes in - it's a 13mm eyepiece with a 100-degree apparent field of view - unheard of in any eyepiece until it came out last year - and if the reviewers are correct, it maintains quality to the edges of this field and also provides great contrast. I can't wait to try it on the 15-inch Obsession and M51 is going to be my first target - just as soon as we get through the required week of rain and clouds ;-)
But I'm not complaining. The clouds have set me to reviewing my whole eyepiece situation and that has led me to evolving a sort of best strategy for using the various scopes I have, most of which were bought with public sessions in mind - but right now I'm in selfish mode. How can I use all these neat toys to my best advantage? Seriously - what I use frequently depends on mood, time available, my energy, seeing conditions at the moment, intended target and did I mention whim? Well - that's closely related to mood.
But as I started down the "best" eyepiece route I kept wandering off related side streets. Here's how it went.
First, having invested $620 in the 'Ethos,' how do I get the most out of it? Well, it will work on each of the scopes and here's what it delivers in terms of power and true field of view as approximated by the power divided into the apparent field of view.
Scope | power | true FOV
15-inch F4.5 | 130X | 46'
8-inch F10 | 154X | 39'
120mm F5 | 46X | 2°10'
100mm F9 | 69X | 1°27'
80mm F7.5 | 46X | 2°10'
66mm F6 } 31X | 3°14'
Next issue - how to double the power - and my solution is the 2X Televue 1.25-inch Barlow I already own. According to the instructions with the Ethos that will not vignette the fov - pleasant surprize there. I had assumed I needed to purchase a 2-inch "Big Barlow" for $200, or a PowerMate for $300. Not anxious to do either, so. . . again, according to the instructions with the 'Ethos' - this is the first eyepiece I ever owned that came with two pages of instructions - but according to these, this 2X Barlow will actually increase the power by a factor of 2.17X. So, my table of powers and fields now looks like this:
Scope | power | true FOV
15-inch F4.5 | 282X | 26'
8-inch F10 | 334X | 18'
120mm F5 | 100X | 1°
100mm F9 | 150X | 40'
80mm F7.5 | 100X | 1°
66mm F6 } 53X | 1°53'
Isn't this fun? But this is only the start. We haven't even touched the exit pupil business yet because it really isn't critical with the 13mm. The exit pupil there is well within bounds. It's with the wider field, low power eyepieces that I get concerned about it. What it boils down to is this. My old eyes can't handle any more than 5mm of exit pupil, I'm pretty sure, if they can handle that. This means for each scope you can calculate an extreme eyepiece size simply by working backwards from what delivers a 5mm exit pupil. Simply divide 5 into the objective diameter of the scope. So, for example, with the 15-inch scope you divide 5 into 375mm which gives you 75X - which is the lowest power I can use. What focal length eyepiece yields that power? Simply divide 75 into 1687, the focal length of the scope. The answer 22.5mm.
So the longest practical focal length in this case is a 22mm Nagler or if I want to stick with lower priced, existing eyepieces, a 21mm Hyperion. Should the 22mm Nagler be high on my list of potential purchases? They sell for $480. On the 15-inch that would yield 77X and a true field of 1°4'. Hmmm... is the extra fov worth the price? The trade offs here are the Nagler gives a 46' fov at 130X, vs 18' more at 77X. On this scope the prime targets are deep sky and the extra power is frequently important, so let's see what the comparative fields look like on a typical object, such as M35.
Aha! What's clear from this is the 22mm Nagler is worth it. Why? Because I not only like how the extra field frames M35, giving you a sense of context, but more importantly it brings NGC 2158 into the picture and I love being able to point out these two simultaneously to people because they are both open clusters of roughly the same size, but NGC 2158 is about five times further away. And what does this say about the Hyperion 21? Well, it's only a slight improvement on the Ethos in terms of field, but the Ethos will deliver almost the same field with significantly higher power, so the 21mm may end up on Astromart.
Now, having jumped to that conclusion, I would not dream of buying the 22mm Nagler without first trying the 21mm Hyperion and the Ethos together because what the Starry Nights simulation does not show you is the difference in power. The Ethos will deliver almost the same fov at 130X as the 21mm Hyperion gives at 80X. i think that's going to be a significant difference that will have to be weighed against the still larger fov - but at 77X - of the 22mm Nagler. And yes, the 22mm Nagler will include NGC 2158 when M35 is in the center of the field of view - but, the 13mm can capture both at once at higher power if you move M35 over to one edge. Bottom line - this is the sort of thing you need to play with - and, of course, i wouldn't make a decision on a single example. But I think it's a good illustration of the pros and cons and complexities of the eyepiece choices.
But to see where exit pupil really makes a difference we need to consider a second example - how this all plays out in the 8-inch SCT. Setting a maximum exit pupil of 5mm on this scope looks quite different. At 200mm a 5mm exit pupil results from a power of 40X. With a focal length of 2000 mm that sets an upper limit for the focal length of a low-power eyepiece of 50mm. Balancing this against apparent field of view of the various eyepiece designs - and price - I came up with a 35mm Panoptic as the best solution. My big assumption here is that Televue deserves its reputation for quality and that others can't match it. But I'm not entirely sure about this. I have an inexpensive ClearVue 30mm eyepiece with an 80 degree apparent field of view.
Oh this is interesting! The 30mm ClearVue (which I think I paid $80 for and is quite nice) gives me the same fov for all practical purposes - and at a higher power (67X vs. 57X) - than the 35mm Panoptic which sells for $380! Of course, I could get a significantly larger field - but at still lower power (49X)- by using a 41mm Panoptic. Of course the 41mm Panoptic is almost in the same cost category ($510) as the Ethos! Hey, I think I'm saving myself some money here! (Wonder if there is an inexpensive - but good - 22mm eyepiece with an 80-degree afov? )
OK - so where we stand now is that the Ethos with 2X Barlow makes a great eyepiece for the 15-inch and 8-inch. That it may be worth it to get the 22mm Nagler, particularly for the 15-inch, but that the 30mm ClearVue is a fine low-power/wide field choice for the 8-inch SCT. Why not use the 30mm ClearVue on the 15-inch? I do sometimes when desperate - but this runs right up against the exit pupil problem. This combination yields an exit pupil close to 7mm and that is wasted on my eye. (Should work for a healthier, much younger person, however.)
It was at this point I began to wonder that if I was heading in the wrong direction entirely by looking at more eyepieces as the solution to nice, low-power view. I got hooked on this idea of wide fields of view decades ago, but now that they are within my reach (financially) and there are several excellent new technical solutions as well - well, I'm not at all sure the super wide fields - at low power - are nearly as desirable as I once thought. What's more, they're easily within reach by piggy-backing small refractors onto the larger scopes. So. . .
Part of the new strategy is to put the 66mm ED (AstroTech) on the LX90 Meade. This works as long as I don't put large eyepieces in both scopes at once - do that and it's hard to balance. But the 66mm would make a wonderful, richest field and finder combination on the LX90. Using it strictly as a finder, a 40mm Plossl would give me a 5-degree fov. With the 12.8 mm lighted reticle it still gives 31X and a 1°36' fov. And if I want a super view of something like the Pleiades or the Double Cluster in Perseus, why then I'll put the 13mm 'Ethos' in it - that yields 31X and a 3°14' fov! Think of using that on the Double Cluster, then zooming in by switching the 'Ethos' to the 8-inch and getting 154X and a 39' fov. Makes me drool! Go away clouds!
What about the 15-inch? I'm sure the same combo would work fine. But I may be able to buck up the piggy back scope to the 80 ED. I'll check on the Obsession online forum to see if someone has tried that - not sure the 15-inch can handle it, though I'm sure it's no problem for the ServoCat. If the 80 ED doesn't work there I think it has been driven to AstroMart by the less expensive 120mm ST achromatic. The reason is the greater light grasp of the 120mm - and I still have the 100mm ED as a great solution for planets and double stars.
In fact this last pair - the 120mm and the 100mm should make perfect mates on the Desert Sky Astro Products dual mount I've ordered. On one side you have the 120mm yielding a 4° fov at 20X with the 30mm ClearVue, and on the other you can have a 9mm TMB Planetary giving 100X in a 36' fov. The 120mm is great for richest field work, but doesn't do well on the planets and moon. But that's just where's the 100mm excels, and both could do a fine job on most doubles.
Hmmm. . . now what's the best way to get high power out of the 100mm ED? Well, since it is on a "push-to" mount all the time - not unlike a Dobsonian - then the wider the fov, the better. That says use the 'Ethos.' At 13mm you get 69X in a 1°27' fov. Put in the 2X Barlow and you have 150X and a 40' fov. To give you an idea what that means, a 6mm TMB would give 150X as well - but a fov of 24' . What's that mean when you're viewing Saturn, for example? Well with the 13mm Barlowed to 150X it will take Saturn about 2.5 minutes - real time - to cross the fov. It would be less than a minute and half for it to pass across the 6mm TMB fov. Bottom line - you will get a much better look before you have to move - and thus jiggle - the scope if you're using the 'Ethos' with a Barlow.
Can you go higher? How about a 3X Barlow? Televue makes one and these don't break the bank - just $110. So - the 3X with the 'Ethos' actually yields 3.25X, reducing the 13mm 'Ethos' to the equivalent of a 4mm. That's 225X and a 27' fov. Not too shabby. But you would need a really good night to benefit from it. On most nights the highest power you could use in the 100mm is 200X, (50X per inch). So would 3X Barlow be worth the $110 investment? maybe. In the 120mm it would give just 150X, well within it's maximum and useful on double stars and such, More importantly, on the 15-inch it would yield 422X and that would be worth trying on an exceptional night. But that's the key. To get the most out of the 3X Barlow I would need an exceptional night.
Oh - and Televue has just announced an 8mm 'Ethos." Is that in my future? I doubt it. What might be in my future is another 13mm Ethos. I mean think of using them both in the Denkmeir binoviewer with the Power Switch that gives me three different powers? Wow! Let's see . . .
(Note to newbies - it wasn't always this way. I've been observing half a century and a good deal of that time my largest scope was a 6-inch Criterion Dynascope and I had three eyepieces - two achromatic Ramsdens and one pricey ($12, I think) orthoscopic. They had apparent fields of roughly 40 degrees , little eye relief, and gave the general feeling that you were looking into a straw. But I did eventually get one fancy, low-power, wide-field eyepiece - a 40mm Kellner.)
Comments
]]>What you didn't mention is the increased contrast you get with higher
magnification while maintaining the equivalent fov. This is perhaps the
biggest factor of all.Pete
Take your average nuclear explosion, mix in a lot of carbon to absorb the blue light, and what you get is one unequivocally red star.
The one I was looking at this morning is called UX Draco and it's a rarity as stars go. Oh, there are several well known stars that are described as "red." Aldebaran, Betelgeuse, and Antares all come quickly to mind. But if we're honest about what we see when we look at these, we should describe them as "orange," ot maybe "reddish," and we shouldn't say that they were "colored" orange, we would say they have an orange "tint."
Truth is, this business of star color can be quite frustrating, especially for beginners - but I know veteran observers - very good, veteran observers - who say they just don't see the colors that others report. And even when I show people a very "colorful" close pair, such as Iota Cancri, and ask them the color of the two stars without any prejudicial advice in advance, perhaps one in three, will report the stars by their textbook description as "blue and yellow." What's more, read any reports of the observations of double stars by veteran observers and you will get all sorts of colorful descriptions of the same two or three stars - descriptions that frequently do not agree with one another.
In my early days of observing I simply could not see the color in stars, except when confronted with an exceptional pair, such as the popular "blue and gold" Albireo. In those days I was a pretty careful observer, sending in variable star reports to the AAVSO where I had estimated the brightness of a long-period variable to within one tenth of a magnitude. Such stars are almost always "red," but I seldom saw them that way. Generally, I just took star colors as wildly imaginative.
Now I feel differently. Now I can't look at Arcturis in the scope without thinking immediately of how beautifully orange it is, and to my naked eye Spica always jumps out as the iciest of blue. Interesting choice of adjectives, I know, since it's rich blue color reveals it as an exceptionally hot star - not icy. But hey, I'm human and in my human experience I think of blue as being cold. But then, in my role as a somewhat normal human I think of stars as tiny little lights - not as roaring, tumultuous, hydrogen bombs in continuous explosion, though that's what they are.
The difference isn't accidental. I didn't suddenly go from being color blind to color sensitive. Nothing to do with age, or equipment, or seeing conditions, though all these play a role, I'm sure, in how we see color. What it has to do with is about five years ago I simply made up my mind I was going to study examples of bright, colored stars - both naked eye and in the telescope. That's when I started to understand that "color" really isn't the proper word to describe what I saw - :"tint" was. The problem is, color differences are indeed subtle and can be exaggerated, or otherwise compromised, when two stars are very close together, such as a telescopic double. But once you become accustomed to noting color differences, you find it hard to believe others don't see them. To me, every time I look at bright, colored stars, their colors now scream at me. Arcturus is Orange - Antares I think I would call red, but just. Betelegeuse and Aldebaran are more orange than red. Rigel is blue and Sirius blue/white, while Capella has an unmistakeable yellow tint. Vega is more blue than white, but certainly not as blue as Spica. Feel free to disagree, of course, but I'm just telling you how I see these now and how I can understand when people give them brilliant color labels that are exagerated - in the end they are tints to me and if I were to paint them I would use pastels or water colors - and with great restraint.
Hmmm. . . come to think of it, maybe that's the difference between my perception of star color in my early days of observing and my perception now. In the interim i had taken up painting and most of my painting was done with pastels and when you have a case of a couple hundred pastels you begin to appreciate the subtleties of different tints. To do the stars I would choose one yellow, one blue, one red - all from among the palest of the groups.
Except when I was trying to capture a carbon star - then I would take deep red, going towards brown but with bits of orange sparks flying from it.
UX Draco and, I suspect, similar "carbon" stars are the exception to the "tint" rule., They are red, not simply to my subjective view, but to the the more objective view of the spectroscope and camera. But don't take my word for it, try it for yourself - and if you do, I'd love to hear your report and I'll add it to this posting. Just email me at gstone@umassd.edu.
There are other carbon stars such as UX Draco, but what I like about this one is it's only 13 degrees from Polaris, so most people should be able to see it year-round. There is a wildcard in this otherwise stacked deck, however - UX is also a variable, changing magnitude from 5.9 - 7.1 over about six months. Does it also change in redness? Apparently. How much, I don't know, nor do I know whether it's redder when at its brigtest or faintest. What I can tell you is when I looked at it about 4 am today I instantly knew which star it was, even though my field of view was quite large and there were several stars in it. UX simply jumped out as the one odd ball in the group. Everything else was distinctly blue or white - it was -well, red.
It was the "Celestial Sampler" of Sue French that got me started on UX Draconis. She featured it in her article on Draco, and that's where I got its color index and variability range.
Here's a couple of finder charts from Starry Nights. Since it's circumpolar, just twirl the large-scale chart around until the Little Dipper matches the orientation of the moment. That circle is 5-degrees, a good binocular field. (Hmm... have to look for this with binoculars.) The second chart has a much smaller circle - about one degree - and I did it in black and white so as not to indicate too strongly which one is UX. When I first saw it, it was not near the center of my field, but it did leap out as different. See if that happens with you.
BTW - want more objective indicator of color?. Consider the "color index" that astronomers use for stars. It goes roughly like this:
-0.33 O5 Blue
-0.17 B5 Blue-white
0.15 A5 White with bluish tinge
0.44 F5 Yellow-White
0.68 G5 Yellow
1.15 K5 Orange
1.64 M5 Red
The middle letter/number is spectral type. Our Sun is yellow with a color index of 0.65. Spica is off the blue end of the above chart with a color index of -0.13. Antares goes off the chart on the red end with an index of 1.8. And UX is really out there on the red side with an index of 2.7.
So if you're seeing red when you look at UX Draconis, it's not your imagination - this one really is red.
]]>I call these programs “silence under the stars” because each program will begin with all participants sitting under the stars in meditative silence for 10 minutes. What follows will include observing where the subject matter will be driven simply by what’s available on that particular night and at that particular time. This will be something more than a guided tour, however, for the universe isn't something simply "out there." It is something intimately related to the formation of life on earth and we will examine these objects with those connections in mind. While this will be something less than a systematic observing class, if participants strive to make one program each month, at the end of a year they should be well-versed in the night sky. The observing at the telescopes will not be silent. But, a portion of the Observing Green will be set aside as a silent sanctuary - an area where participants can retreat to if they would like to resume the silent, meditative approach.
During each program we will observe a variety of astronomical objects, near and far. But what is critical is the frame of mind in which we approach these observing opportunities. That’s the reason for beginning in meditative silence. That's the reason for exploring the connection of these objects to us.
The silence begins by everyone taking a seat on the Observing Green. Our objective is simple: Quiet our “monkey brain” – which means for each of us to pause and let all the normal cares of the day from political to personal – seep away, and focus on the cosmos – the universe above and around us.
If this feels a little bit like going to church, so be it. But my aim is not to promote any particular religious ideas. It's merely for us to be focused so we can see the story that nature tells. I take my cue from one of the greatest scientific minds of all time, Albert Einstein, who said so eloquently: "The most beautiful thing we can experience is the mysterious. It is the source of all art and science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead; his eyes are closed."
I want to be alive, with eyes wide open, when I go to the telescope – and I want live people with eyes wide open sharing the telescopes with me, and that means we all must be able to “pause to wonder and stand rapt in awe.” That is what this opening 10 minutes of silence is about. It is a time to tune ourselves - to prepare ourselves to experience the mysterious. And while on one level what we will experience – the planets, the stars, nebulae and galaxies – is no longer mysterious, on a much deeper level it remains well beyond our common reach. Yet, here we are, connecting directly with it. Look at the tiniest speck of light in the sky – the dimmest of stars – and you are directly experiencing forces that defy our wildest imagination – incredible nuclear explosions, contained by the gentle, yet all pervasive force of gravity. And those forces are essential to our very existence.
You also are stepping back in time, looking not merely at dots of lights, but at a distant timescape where each dot represents a different point in history, for those very real photons – that energy from those continuous nuclear explosions – has been traveling our way for years, sometimes centuries – and some of the things we can see, even with simple backyard telescopes, sent their light on its journey to us at a time when dinosaurs walked on the very spot where we now sit.
We cannot begin to understand all that, except in the most superficial way. But we can talk about it, we can observe it, and we can experience it. It is this last – the actual, real-time experience – that these observing programs at Driftway Observatory are all about. This is why I do them, this is why I invite you to participate, and this is why I ask that we all do our best to approach them in silence and in awe – awe for the universe itself where all of us can connect. We all are made of star dust – the stars above us, still reaching out to us with their photons, are also our heritage. In these skies, in stars such as these, every atom that fills our body and makes us so special, so different from anything else we know in the universe - was forged.
Like gravity, the weakest of the four fundamental forces of nature, as individuals we are very weak. But like gravity, in our collective wisdom spread over time, we may well be one of the most significant forces in the universe, for we are the universe becoming aware of itself – we are the conscious universe.
So please – when you come here at night – make a special effort to reconnect with your most distant ancestors, your birthright, and your future – the stars. And please, begin that effort in meditative silence, bringing your mind and entire being to a sharper focus.
While I have half a century experience of looking at the stars and so can serve as a sort of guide and coach, I am not an astronomer. Vincent van Gogh summed up my feelings when he said:
"For my part, I know nothing with any certainty, but the sight of stars makes me dream."
Greg Stone
Driftway Observatory
Julian Day: 2454650.58358
This was a wonderful, refreshing session, though cold got to my hands once ina while. What I did most of the time was play with the Orion 120ST and compare it, once in a while, with the 100ED. No shocks. Bottom line is this: The 120ST is a nice scope and lots of fun to use on galaxies, nebulae, open clusters and the like. It starts to break down when it comes to challenging doubles, and there's no doubt it puts a purple halo around bright stars and the so-called "fringe killer" can maybe cut this in half, but won't eliminate it. The 100 ED excels, as expected, on double stars, planets, and the moon. Hardly a hint of a purple halo on Vega.
I also did some more testing of the "Constellation View " binoculars. Conclusions: They do, indeed, show me how others see the Milky Way under clear skies with no light pollution. They also help put things into perspective. For example, they capture the entire region from Albireo to Altair, so you can see the relationships among these two stars, Saggita, the Coathanger, and M27 - though I could not detect M27. In a funny way, it makes that whole area seem smaller!
BUT. . . the 5X25 Xtra wides from Bushnell do almost as well. They capture the area from Albireo to Saggita and DO show the Coathanger easily - had to work to see it in 2.3X40s - and I felt I could see - detect - M27. Bottom line - the 2.3X40s are fun, but I would most likely reach for the 5X25 when on a "scouting mission" to, for example, get clearly in mind the location of M11.
More specifics:
M84-86 - When I started this session the Virgo Cluster was still reasonably high in the west. I could find M84 easily, but had trouble when I changed eyepieces. Took me a while to figure out that the balance was off and the scope on the Voyager count was front heavy so that when I removed an eyepiece, the objective end fell slowly, changing the pointing. Put in another eyepiece and I was completely lost.
Balancing corrected I found it wasy to locate M84/86, the eyes (NGC4435 and NGC 4438), and two more galaxies in Markarian's Chain. I suspect these last two were NGC 4473 and 4477, judging from positon and brightness. Not bad for a 120mm operating at 25X and 46X - especiallys ince at thi spoint they were only about 37 degrees high. (If I had caught them near midnight they would have beenc lose to 61 degrees high, a significant difference.
]]>At 32 and below I need chemical toe warmers and handwarmers to be comfortable, plus silk glove libers and heated vest. I need hat on top of balaclava plus scarf
At 32 - 50 - Silk glove liners are enough - heated vest is optional, but a hoodie plus winter coat can do the trick. wool hat alone works. Scarf optional.