Tag Archives: telescope

Recent intermission

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Reading time has been rather gobbled up.

I may have selected this based on a subconscious connection with grass and the breaking of impenetrable sod:

Somehow I have managed to miss reading it down all the years; meeting as an adult, it raised quite a few questions.  One concerns the apparently reckless way the father takes his family off on a dangerous journey.  We have gone soft now.  Or perhaps it didn’t seem as dangerous, when any life was dangerous – even staying tucked into the most secure and prosperous home could not protect you from the epidemics of infectious disease which cut swathes through many a family.  Or perhaps pressure of poverty was strong enough to drive the migrants on. Then there’s the way Ingalls apparently makes the decisions without input from his wife (ah the good old days – ‘she for god in him’ etc.) And worst, of course, are the passages dealing with the native Americans.  Ingalls is portrayed as liberal, humane, but assumes that the western country is his to take because the inhabitants “weren’t using it”, and he is furious when, having illegally moved into Indian reservation land, he and other settlers were required to leave “their” farms. Ugly.

Then there is this delicate little sippet of a book.

Ah, the pure sensory pleasure of its satiny dust jacket, the smooth crispness of the coated paper, the careful balance of text and image, the reposeful colours, the spine coherent without wilful springiness, the clean smell rising from every page turn. This made it quite difficult to concentrate on the actual subject matter, but it too was charming in its miscellany of science, technology, art and history, and although the coverage is very slight, there’s a further reading list handy at the back.

One phrase, though originally intended to be satirical, spoke truth to me as an observer:  Thomas Tomkis in 1615 characterised a telescope as “an engine to catch starres”.  Out in the darkness with the Dob, that’s just what it feels like.

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Is it lunchtime yet?

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Or bedtime?

Because I didn’t have to get up at seven I woke at four.  As I blearily tweaked the curtain, Jupiter glowed in a frosty sky, and I could hear it even when I tried to tuck back under the quilt:  “You’ll be sorry if you don’t… you’re awake anyway … you’ll be sorry if you don’t.”  Luckily the thermals were to hand in the darkness.  And the essential fluffy feet.

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It’s quite a while since I’ve been out at this barbarous hour.  The Plough of course; Leo; Virgo arranged around the beacon of Jupiter; Hercules; Lyra rising.  I fail to like Boötes, whereas my cockles always warm to Corona Borealis and Serpens Caput (as if they cared!), and Draco provokes tragicomic nostalgia.  In the still air, each wave was audible, growling onto the remote beach, the seventh waves thundering and dumping with suppressed energy.

I took out the 5″, but it had decollimated itself so I could barely pick out the belts of Jupiter, though it was pleasant to see the four big moons in a row.  So I stuck to eyeball and binocular, working to ‘see’ the squashed house of Cepheus, which for some reason my brain never identifies even when I know I’m looking straight at it.  Cygnus came up in the east, and at last Aquila began to appear, and the whole summer triangle was absurdly simultaneous with the icy car and crunching grass.  A shred of the waning moon rose at six, and through binoculars the earthshine was awesome.

One planet; one meteor; one satellite; the moon; and a thousand stars.  As I came in I dropped the 5″ on its head, poor thing, and made it more woggly than ever.  So now – if you can – collimate THAT.

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A few bays along …

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… from my usual.  (Click a thumbnail for the gallery)

I abandoned my companions with indecent haste, raced home for the binoculars and the grab-and-go scope, and was out the front door in time to catch the infant moon before it dipped into the trees.  Its horns were as fine as threads.  I could see the disc of earthshine they embayed, while the sky darkened, and the air began to bite.

Revelling in the cold

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The revelling won’t last, though I daresay the cold will.  So I nipped out with the 10″ to take a quick look at the Moon, as everything else was wiped out by it.

I always like the waxing gibbous phase, which conveniently brings some of my favourite features to the terminator.  I took a lot of snaps through the eyepiece; always frustrating to find that while one segment is pretty good, other areas come out blurred.  And the Moon image in the eyepiece was surprisingly zizzy considering it isn’t warm, which won’t have helped to get a sharp image.  I’ve turned the pictures upside down to make them right way up, and now they look peculiar to me.

1-waxing-gibbous-10-nov-2016There’s something very satisfying about Clavius, with its arc of smaller craters diminishing gradually in size like Russian dolls.  The camera managed to pick up the central peak in Rutherfurd (on the southern rim) and the smaller craters D C N and J (running away from Rutherfurd in an arc).  The unevenness of the crater walls is obvious, and I see there is a tiny hint of the rather mashed down central peaks (inboard of C, as it were) and hints of some of the other minor craters in the interior.  I haven’t attempted to identify all the surrounding craters – this part of the surface is a bit busy.

2-clavius-10-nov-2016And I have a fondness for Gassendi.  I think it was one of the first craters I learned by name, with its very distinctive shape where Gassendi A breaks the main crater wall.  This image caught some of the detail – the long ridge leading away to the east just catching the sun, the slump or depression in eastern wall, the break in the wall to the south, and just a hint of the concentric ridge which lies within the south wall.  Also a hint of the raised material inside the northern rim where Gassendi A intrudes. It would be too much to expect to image any of the rimae with my feeble equipment.

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On the hydrogen alpha line

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Standard warning for non-astronomers:

Never look at the sun with your naked eyes, and especially not through any optical instrument such as binoculars or telescope as this is likely to cause permanent blindness.  The photos were taken through a specialist solar telescope which filters out almost all the sun’s light – never attempt to make a filter yourself.

Today there was enough sky, which was just as well, as I fiddled with the feeble tripod, trying to make minute adjustments with knobs which were only designed for coarse movements.  Even using a 35mm eyepiece the sun soon roamed off and away, and with a short eyepiece I spent more time chasing the image than observing it.  And it was hot.  And things were biting me.

Of course if you could get a straight look, it was wonderful. The hydrogen alpha emission line is in a beautiful red part of the spectrum, and in the eyepiece it shines.  In that moment when the focus was fine tuned, and the tripod stopped wobbling, the tiny image revealed a huge prominence, looking simultaneously as delicate as a veil and as monstrous as an apocalypse, rising and flying above the sun’s disc.  Then the image moved off, and it was back to the twiddling and wobbling again.

And the pictures.  Not astrophotography; that suggests something technical, planned, managed, processed, stacked.  With my basic equipment, it’s a challenge even to get the camera focused and steady. Nor are these snaps.  The images do not look like what I saw in the eyepiece, because the camera can’t render the perfect vermilion the eye translates; and to make any of the detail which the eye saw appear on the photographs, they have been tweaked using the primitive capabilities of iPhoto.  So here they are: pictures, anyway, artificial in any sense of the word.

One tweaked to reveal a hint of the delicate complexity of the largest prominence:

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and one fiddled with to show something of the active sunspot areas and even, I am amazed to see, some of the filaments crossing the disc:

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If you want to see what the prominence ‘really’ looks like try this link, and then click on the image to see it breathtakingly full size:

http://spaceweathergallery.com/indiv_upload.php?upload_id=129260&PHPSESSID=13ne21ph75ssvvpq8mopn98bj7

But of course it doesn’t ‘really’ look like this.  Even in hydrogen alpha.

Perfectly maddening

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Tiny jigsaw pieces of sky between clouds before the rain came in.  I gave up on the solarscope but because the 5″ tracks I was able to take a few glimpses through the Baader filter.  No good photos though, just a fuzzy one.

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Standard warning for non-astronomers:

Never look at the sun with your naked eyes, and especially not through any optical instrument such as binoculars or telescope as this is likely to cause permanent blindness.  The photo was taken through an astronomy grade white light filter  – never attempt to make a filter yourself.

Do you know what it is yet?

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Far too many photons dashing about last night; it was a push to find even Vega by eye.  But there was sky, so waste not want not – take out the big scope and the camera.  This is silly for so many reasons, relating to deficiencies in all the equipment, in the observing conditions, and in the photographer, but as dear Mehitabel would say, wotthehell.  (The pictures may be more informative if you click into one for the gallery. Or possibly not.)

Tuning the etalon

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And I’m still quite excited that I have my very own etalon to tune.

I risked heatstroke today for an observation with the solar scope.

The red image is beautiful and I could see the active region which is about to rotate off the disc, some prominences including one which was showing the classic loop shape, and filaments looking darker on the bright background.  I am still training my eye and learning what can be teased out from the image with different eyepieces and by twiddling the ring which supposedly adjusts the etalon – handicapped by having the scope mounted on a flimsy camera tripod which wobbles like a b****r if you even breathe on it, and which of course has to be manually adjusted every couple of minutes as the sun moves out of the eyepiece.

Photography is an even more annoying animal, though I did get my little Canon out for an experiment.  Quite apart from the wobbling thing and the lining up with the eyepiece thing and the focusing thing there is the exposure thing:  based on today’s photos, if the exposure is long enough to reveal the prominences, the disc is so over-exposed that the filaments and even the sun spots disappear, and vice versa.  And the camera can’t render the gorgeous vermilion of the image at all.

Sun 22nd Jul 2016

For what it’s worth, here is a fuzzy and almost featureless image of the sun but NB it does actually show some prominences.  The eye of faith might even discern some indication of the active region (at about half past two on the disc).  So this is progress.  Let’s worry about focusing another time.

And did I get sunstroke?  No; in true astronomer fashion (who cares what people think?) I fended it off by putting a small ice pack inside my hat.  Dribbly!

Warning to non-astronomers:  never look directly at the sun, especially not through any optical equipment such as binoculars or telescope, as permanent blindness is the likely result. The solar telescope I use is  specialist astronomy equipment, which excludes almost all the light of the sun and is therefore safe to use.

Things to do when you can’t sleep: lxii

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lxii  :  Grab and go

At 4.00 it was deplorably clear that sleep would not come again.  By 4.10 the legs were being stuffed into thermals.  At 4.15 I was saying good morning to the Summer Triangle.  And at 4.20 the 5″ and I, randomly embraced, went teetering out of the front door in the dark like Laurel and Hardy.

Saturn and Mars are both tucked down in Scorpius.  Mars in particular is making Antares look feeble; opposition is next month.  It should be possible to observe some planetary detail by now, but the scope and I were both bleary from our sudden bounce from cosiness to cold, and there was no time to get clever with either planet.  Saturn too is approaching (opposition in June) though unfortunately it will not be high in the sky even then – I always have trouble observing Scorpius as it tends to get tangled in the local trees.

By 5.00 the cosmos was vanishing into the unmeaning blue.  Although dawn was coming in at 3°, and the grass was stiff with frost, summer must be on the way.

Two of everything

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Last night: Two tops; two skirts; two pairs of leggings; two coats; double socks; two hats.  Only one pair of boots though, only one pair of fingerless gloves. It took half an hour to put it all on, and then I could barely bend in the middle, which was a pity as Jupiter was just rising and the telescope was almost horizontal.  As the planet rose this became easier and I tried to tease detail out of the image, swapping different eyepiece and filter combinations in and out, and as usual cursing the moon, the motorists, and the neighbours who would insist on going to the bathroom with the light on.  It wasn’t a classic night, but I watched the end of Io’s transit (fuzzy in the low level murk), could distinguish the knotty appearance of the north equatorial belt, and eventually began to see the Great Red Spot appearing over the limb of the planet.  Mem to self:  practise collimation.  Between times I did a bit of binocular work, drank tea, and watched frost settle on the car.  When I found that the seat where my bottom wasn’t was covered in hoar frost, it was time for bed.  It took half an hour to take it all off …