> From dpeach_78@yahoo.co.uk Thu Nov 28 07:43 MST 2002
Date: Thu, 28 Nov 2002 14:42:58 +0000 (GMT)
Subject: Jupiter Images (Nov 27th.)

Hi all,

Here are some Jupiter images from Nov 27th, caught
through a brief clearing in the rain clouds.
Weather has been dismal the last few days.

Despite the conditions, seeing was good, allowing the
GRS area to be captured. The NTB really seems
faded on the f. side of the disk. Also note the small
"white cloud" on the f. side of the GRS. The dark
shadow is cast by Ganymede. Also note the closeness of
one of the SSTC ovals, with one of
the cyclonic STZ spots.

Best Wishes

Damian

-------------------------------------------

JUPITER IMAGES, NOVEMBER 27th, 2002.

D. A. Peach, Costa del Silencio, Tenerife, Canary Isl.
12" (30.5 cm) Meade SCT @ f/21.0. SBIG ST-5c camera.
SBIG RGB Filter set.

Total Exposure Times:

Integrated Light: ~45 x 0.12 secs
R/G/B + IR Rejection: 4-6 x 0.35 - 0.75secs.

Seeing good (6-8), but Transparency highly
variable/poor
with frequent low and high clouds + high haze (clouded
- 4.0mag.)
No wind. No dew.

Equatorial Diam=39.7"
Altitude= 63 degs.



> From jhr11@hermes.cam.ac.uk Thu Nov 28 13:48 MST 2002
Date: Thu, 28 Nov 2002 20:48:18 +0000 (GMT)
From: "J.H. Rogers" <jhr11@hermes.cam.ac.uk>
Subject: Re: Jupiter Images (Nov 27th.)

Hi Damian,

Thanks for those very useful images of Jupiter - and that beautiful
image of Saturn.

In your Nov.27 image of the GRS, that white spot in the f. side could
indicate that Ed's ring of Nov.23 is indeed circulating rapidly round
the GRS (contrary to my hypothesis!).  However it may be more
complicated. Can you send the less-processed version of this image, so
we can see the Np.  side free from rings around the shadow of
Ganymede?

Re Saturn, may I sound a further note of caution about image
'sharpening'?  I think one reason that various 'divisions' have come up
strongly on your images (and also on Ed Grafton's) is that they have
been sharpened using a radius that matches the separations between the
bands in the rings. You can see this in the band that runs round inside
the limb of the planet, and in the way the 'divisions' in Ring A merge
as one goes to the minor axis, as well as other exaggerated dark bands
in the rings (e.g. a dark division surrounding Ring C).  Comparing with
the image by Thierry Legault, and by the Hubble Space Telescope last
year, it seems that the image processing has converted steps or
gradients of intensity into apparent minima.  Stunning picture though!

Congrats on keeping up the good work!
Best wishes,
John.

_________________________________

John H. Rogers, Ph.D.
Jupiter Section Director,
British Astronomical Association.