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crazy observing advice?!

Discussion in 'Observing Celestial Objects' started by kevan hubbard, Aug 12, 2018.

crazy observing advice?!

Started by kevan hubbard on Aug 12, 2018 at 4:14 PM

8 Replies 334 Views 1 Likes

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  1. kevan hubbard

    kevan hubbard Well-Known Member

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    Recently I picked up a book from a book swap place I sometimes frequent,the book is called 'the sky watchers handbook'by Colin a.Rowan published in 1985.it contains the following advice in the section on solar eclipses;' the short period during which the photosphere is covered is the only time it is safe to study any part of the sun with optical equipment. Binoculars can then be used to pick out the detailed structure of the corona. These observations must cease the instant any part of the photosphere is uncovered.'only a lunatic would do this as how can you predict the exact second the Bailey's beads will appear with their blinding light,magnified at about 7 to 10 times through most common binoculars! Binoculars would be even worse than a telescope as you'd suffer serious damage to both eyes not just one!
     
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  2. Dave In Vermont

    Dave In Vermont Well-Known Member

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    I surmise 'Colin' never heard of filters or projection. Did we even have the filter-tech back in '85?

    I'd use that book as a curio only. Cool find though.
     
  3. kevan hubbard

    kevan hubbard Well-Known Member

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    It did have a good section on nacreous and noculient clouds.I saw some noculient clouds about a month back. These form at about 50km up and how they form is unknown probably meteorite dust? They've been seen on Mars too.nacreous clouds form at about 12 km up and tend to be in polar areas don't think I've seen these?both types are seen at dusk and are under lit by the set sun.like the polar lights,zodiacal lights, etc,are sort of on the border between earth watching and astronomy.
     
  4. Dave In Vermont

    Dave In Vermont Well-Known Member

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    Lenticular Cloud in PNG.png
    "Shhhh! They're listening!"
     
  5. kevan hubbard

    kevan hubbard Well-Known Member

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    That is I think a lenticular cloud.nacreous are much higher up in the stratosphere and noniccular I'm guessing in the mesosphere? How both types form is a bit of a mystery as there's very little moisture up there.it's thought that nacreous clouds may some syphon of moisture from high cirrus clouds and drag it higher up but by what mechanism nobody knows.
     
  6. Dave In Vermont

    Dave In Vermont Well-Known Member

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    That's a Lenticular Cloud alright.

    Or, perhaps, a Flying-Saucer..... :p
     
  7. kevan hubbard

    kevan hubbard Well-Known Member

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    I've seen pictures of loads of UFO clouds.I'm not sure how they form with that shape?a trans polar flight would be a great way to see nacreous clouds. We're spoilt for choice in the northern hemisphere. Loads of USA/Canada to/from Europe flights transit the artic. The southern hemisphere not easy,as apart from special tourist flights, only one seems to clip Antarctica that being the Sydney Buenos Aires flight which gets to 71 degrees south thus flying over Antarctica or a bit of it.I think that this flight might be a joint venture between Qantas and the Argentine national airline?
     
  8. aeajr

    aeajr Well-Known Member

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    It is clear he is talking about unfiltered optics. I would guess somewhere else he talks about solar filters. Or perhaps in 1985 solar filters were very expensive and not within the range of his expected audience.
     
  9. kevan hubbard

    kevan hubbard Well-Known Member

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    Pretty sure he means viewing the sun with unfiltered binoculars during the short,and difficult to predict, time the sun is fully covered by the moon.Mylar blankets where certainly available in 1985 as I've seen pictures of runners,etc, covered by them.some people figured it could be used as a solar filter which of course was not what it was designed for so how safe it is I know not?safer than the filters screwed into eye pieces for sure.
     

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