Jupiter and the Great Grey Spot (and bands)

I have just received notification that my friend Tom Wales has completed
the construction of an 8" dob and last night was first light for the
instrument. It would seem that Tom's first attempt at telescope
construction was quite successful.

With this new instrument, Jupiter reveals an orange tinted system of bands.
It follows to me that had the GRS been visible, it too would have displayed
color. Therein lies my query. Through my Meade 114mm reflector and my
Meade 12.5 inch reflector I get superb structural details of the bands --
revealing all that could be expected from instruments their size. . .and,
the GRS is, at moments of exceptional seeing, very well defined but I don't
get any color at all to speak of. Sometimes I perceive a greyish looking
tan hue, but nothing stark and pleasing to the cones of my eyes.

What do you see when you look at Jupiter through your scope? Are you
getting a nice, colorful image and, if so, why do you think that is?



--
Martin R. Howell
"Photographs From the Universe of Amateur Astronomy"
http://members.isp.com/universeofama...nomy%40isp.com

I'm afraid that the Great Red Spot has been rather pale for over two
decades. Part of it has a definite dark pinkish hue (near the center
and towards its southern half), but the rest is almost colorless. The
belts tend to be a reddish-brown (especially the two equatorial ones),
but the colors are more pastel than the vivid "color enhanced" tones one
might see in spacecraft imaging. Clear skies to you.
--
David W. Knisely
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

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On Tue, 21 Jun 2005 17:24:55 -0700, "Martin R. Howell"
wrote:

What do you see when you look at Jupiter through your scope? Are you
getting a nice, colorful image and, if so, why do you think that is?

In 8-12" scopes I see the GRS as a very unsaturated pinkish beige. In
webcam images it is slightly more saturated, but still nowhere near red.
I think it started fading ten or twenty years ago; maybe it still is
fading (in color, not size).

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Arthur Clarke anticipated this too: "It's losing its stain".
"Explore all worlds but dont go to Toronto"!

O.


Chris L Peterson wrote:

On Tue, 21 Jun 2005 17:24:55 -0700, "Martin R. Howell"
wrote:

What do you see when you look at Jupiter through your scope? Are you
getting a nice, colorful image and, if so, why do you think that is?

In 8-12" scopes I see the GRS as a very unsaturated pinkish beige. In
webcam images it is slightly more saturated, but still nowhere near red.
I think it started fading ten or twenty years ago; maybe it still is
fading (in color, not size).

_________________________________________________

Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

Olga wrote:
What do you see when you look at Jupiter through your scope? Are you
getting a nice, colorful image and, if so, why do you think that is?



The GRS is, at the moment, "The Great Pale, Salmon-Pinkish Spot".
While there is a wealth of color visible across the face of the planet
(from the rich milk-chocolate of the major bands to the distinct
turquoise-blue of eruptions out of the bands, the brilliant white of
ovals, yellow and gray swirls within the bands and around the GRS,
charcoal gray 'blemishes' scattered across the spaces between the
bands, etc. etc.) much of this color is aperture/seeing-dependent.

Even in my 28" there are moments when the colors fade; hence my comment
that some of this is "seeing-dependent".
Last night I stopped down the aperture with off-axis masks of 12", 8"
and 4" to see what affect this had on color perception.
As expected, the colors were not nearly so obvious and striking at 12"
and even less-so at 8" (the GRS appeared more gray-ish) and, at 4",
were almost all washed out to near-monochrome.
This last (4") observation comes with the "seeing-dependent" caveat,
again...for there are times when I can definitely see the 'red' tinge
of the GRS with this aperture.

Mike Harvey

On 22 Jun 2005 07:24:29 -0700, "Mike" wrote:



Even in my 28" there are moments when the colors fade; hence my comment
that some of this is "seeing-dependent".
Last night I stopped down the aperture with off-axis masks of 12", 8"
and 4" to see what affect this had on color perception.
As expected, the colors were not nearly so obvious and striking at 12"
and even less-so at 8" (the GRS appeared more gray-ish) and, at 4",
were almost all washed out to near-monochrome.
This last (4") observation comes with the "seeing-dependent" caveat,
again...for there are times when I can definitely see the 'red' tinge
of the GRS with this aperture.

I find the pale orange-pink cast to the GRS quite easy to detect in
5&6" scopes. The wavelength absorpton due to water vapor and other
constituits in the atmosphere are variable and hence, detection of
subtle colors varies accordingly.

D Chaffee

You guys are not allowed to see colour in the GRS "hollow" -
there is no colour there "in the hollow" according to __________________
at SAA.

B.



Dan Chaffee wrote:

On 22 Jun 2005 07:24:29 -0700, "Mike" wrote:


Even in my 28" there are moments when the colors fade; hence my comment
that some of this is "seeing-dependent".
Last night I stopped down the aperture with off-axis masks of 12", 8"
and 4" to see what affect this had on color perception.
As expected, the colors were not nearly so obvious and striking at 12"
and even less-so at 8" (the GRS appeared more gray-ish) and, at 4",
were almost all washed out to near-monochrome.
This last (4") observation comes with the "seeing-dependent" caveat,
again...for there are times when I can definitely see the 'red' tinge
of the GRS with this aperture.

I find the pale orange-pink cast to the GRS quite easy to detect in
5&6" scopes. The wavelength absorpton due to water vapor and other
constituits in the atmosphere are variable and hence, detection of
subtle colors varies accordingly.

D Chaffee

I can't say I've ever seen the GRS visually through my scope. Jupiter
itself appears much like as you describe it - as an offwhite/tan colour.

Tony

"Martin R. Howell" wrote in message
...


I have just received notification that my friend Tom Wales has completed
the construction of an 8" dob and last night was first light for the
instrument. It would seem that Tom's first attempt at telescope
construction was quite successful.

With this new instrument, Jupiter reveals an orange tinted system of
bands.
It follows to me that had the GRS been visible, it too would have
displayed
color. Therein lies my query. Through my Meade 114mm reflector and my
Meade 12.5 inch reflector I get superb structural details of the bands --
revealing all that could be expected from instruments their size. . .and,
the GRS is, at moments of exceptional seeing, very well defined but I
don't
get any color at all to speak of. Sometimes I perceive a greyish looking
tan hue, but nothing stark and pleasing to the cones of my eyes.

What do you see when you look at Jupiter through your scope? Are you
getting a nice, colorful image and, if so, why do you think that is?



--
Martin R. Howell
"Photographs From the Universe of Amateur Astronomy"
http://members.isp.com/universeofama...nomy%40isp.com

"Tony Pottrell" wrote in message
news:1119517289.238013d4ac0be4e60719e44e3d925266@t eranews...
I can't say I've ever seen the GRS visually through my scope. Jupiter
itself appears much like as you describe it - as an offwhite/tan colour.


Once upon a time long long ago, it actually showed as a dark rich salmon
color through my orange tube C 8.

Alas those days are long gone............................
























Allan


--
Only A Gentleman Can Insult Me And A True Gentleman Never Will

Martin R. Howell wrote:
With this new instrument, Jupiter reveals an orange tinted system of bands.
It follows to me that had the GRS been visible, it too would have displayed
color.

I refer to it as the "Spot formerly known as Red."

Mojo
--
Morris Jones
Monrovia, CA
http://www.whiteoaks.com
Old Town Astronomers: http://www.otastro.org