Sirius scintillations in a winter's sky

The seasons have shifted and it's back to that time once again, when
you see Sirius shining brilliantly in a cold winter's sky, like a
heavenly diamond suspended above a snow covered landscape and
scintillating through all the reds, greens and violets... 'tis like
the
magic of being in a dream world!!!

Question: in the Austrian Alps at around X-mas time, if you were
staying there for 6 nights, what are the odds that you will
*definitely* get a snowy night with clear skies when you can
experience the above magic?!

I'm planning on going, but would be well disappointed if (a) it didn't
snow, and (b) there wasn't clear skies on any of those six nights to
see the magic of Sirius!

What are my chances?

Abdul Ahad

Question: in the Austrian Alps at around X-mas time, if you were
staying there for 6 nights, what are the odds that you will
*definitely* get a snowy night with clear skies when you can
experience the above magic?!

Odds seem high to me.

_______
Blog, or dog? Who knows. But if you see my lost pup, please ping me!
A
HREF="http://journals.aol.com/virginiaz/DreamingofLeonardo"http://journal
s.aol.com/virginiaz/DreamingofLeonardo/A

(AA Institute) wrote in message . com...
irius
The seasons have shifted and it's back to that time once again, when
you see Sirius shining brilliantly in a cold winter's sky, like a
heavenly diamond suspended above a snow covered landscape and
scintillating through all the reds, greens and violets... 'tis like
the
magic of being in a dream world!!!
[snip]

Abdul Ahad


So, Mr. Ahad, can you or anyone explain why Sirius does sparkle so
like a quality blue diamond?

I believe it is the brightest star in the sky. Is that why?

Double-A

(Double-A) wrote in
om:

(AA Institute) wrote in message
. com... irius
The seasons have shifted and it's back to that time once again, when
you see Sirius shining brilliantly in a cold winter's sky, like a
heavenly diamond suspended above a snow covered landscape and
scintillating through all the reds, greens and violets... 'tis like
the magic of being in a dream world!!!

So, Mr. Ahad, can you or anyone explain why Sirius does sparkle so
like a quality blue diamond?

I believe it is the brightest star in the sky. Is that why?

The fact that it has the greatest "apparent magnitude" (although not
intrinsicly the brightest) combined with being rather low in the sky (hence
you are observing through a lot of atmosphere) often cause Sirius to
scintillate (romantics say "twinkle") more than any other star.

AA Institute wrote:

The seasons have shifted and it's back to that time once again, when
you see Sirius shining brilliantly in a cold winter's sky, like a
heavenly diamond suspended above a snow covered landscape and
scintillating through all the reds, greens and violets... 'tis like
the
magic of being in a dream world!!!

Question: in the Austrian Alps at around X-mas time, if you were
staying there for 6 nights, what are the odds that you will
*definitely* get a snowy night with clear skies when you can
experience the above magic?!

Snow is not the problem. There already is snow in the Alps and the
skiing season has already started. It all depends on the height of
your location.
As for clear skies: Hard to tell. But with 6 nights available you would
have a very bad luck if not one of them turned out to be clear.

--
Karl Heinz Buchegger

Double-A wrote:


So, Mr. Ahad, can you or anyone explain why Sirius does sparkle so
like a quality blue diamond?

Interesting you mention 'blue' as one of the many colours produced by
scintillation. To my eyes, green is always the most prominent, followed
by red and blue in roughly equal measure (I'm talking purely on the
basis of naked eye observations here). I think we have slight
differences in retinal colour balance between one person and another...

I believe it is the brightest star in the sky. Is that why?

Indeed the brightness of Sirius is a factor making it more visibly
'exciting' to the naked eye. However, the amount of flickering light
and shimmering colors displayed by a star is generally very much
dependent on its altitude above the observer's horizon. The lower down
in the sky the star, the greater the twinkling effect, because its
light is having to reach is by penetrating a thicker layer of the
Earth's unsteady atmosphere.

Abdul Ahad

Double-A wrote:


So, Mr. Ahad, can you or anyone explain why Sirius does sparkle so
like a quality blue diamond?

Interesting you mention 'blue' as one of the many colours produced by
scintillation. To my eyes, green is always the most prominent, followed
by red and blue in roughly equal measure (I'm talking purely on the
basis of naked eye observations here). I think we have slight
differences in retinal colour balance between one person and another...

I believe it is the brightest star in the sky. Is that why?

Indeed the brightness of Sirius is a factor making it more visibly
'exciting' to the naked eye. However, the amount of flickering light
and shimmering colors displayed by a star is generally very much
dependent on its altitude above the observer's horizon. The lower down
in the sky the star, the greater the twinkling effect, because its
light is having to reach is by penetrating a thicker layer of the
Earth's unsteady atmosphere.

Abdul Ahad