LtE in CMO #262

From Edward Arnold GRAFTON

From: egrafton@ghg.net (Ed Grafton)

Hi Guys, The sky was quite hazy in Houston in the early mourning hours of July 6th. However it was also very steady and I can't really complain since a couple of hundred miles west of here 25 inchs of rain has fallen in the last few days. The image data is below:

Taken with a C14 @ f/27 with a ST5c from Houston Texas July 6th at 10:01 UT.

L=15 x 8 sec

R=G=B= 3 x 10 sec

Uranus is about 3.8 arc seconds and the moons range in brightness from about 13.8 to 14.8 magnitude.

Processed CCDOPS, Megafix, Photoshop.

Image : http://www.ghg.net/egrafton/u7-6-02.jpg

From: egrafton@ghg.net (Ed Grafton)

Hi Guys, Here is a Uranus Observation from July 12th 2002 at 09:47 UT

Photometric Data form the July 12th image with Titania used as a reference based on a HST observation a few years back when Uranus was at opposition.

Titania mag 13.49 (reference)

Oberon mag 13.64

Ariel mag 13.71

Umbriel mag 14.01

In the July 12th image Umbriel is embedded in the noise and shows the most deviation from the expected values. The other three moons were well place for sampling.

The sky was average transparency 5/10 and the seeing was good to excellent 7/10. There was heavy due with the temperature in the mid 70s and no wind.

Taken with a C14 @ f/27 with a ST5c from Houston Texas July 6th at 10:01 UT.

L=15 x 7 sec clear filter

Image : http://www.ghg.net/egrafton/u7-12-02.jpg

From: egrafton@ghg.net (Ed Grafton)

Hi Guys, The sky was both transparent and steady in Houston Texas in the mourning hours of 07-19-02. Some longer exposures than normal were used this session to try and coax out the fainter fifth moon of Uranus, Miranda. I have not seen any amateur images of Miranda so this may be the first time it has been captured with modest equipment. The sky was very clear, 9/10, and very steady 9/10. No wind and moderate dew was present.

Here is the Uranus Observation from July 19th 2002

The image can be viewed at:

http://www.ghg.net/egrafton/7-19-02c.jpg

1) The upper left image shows the four brighter Uranus moons and the fainter fifth moon Miranda. This image was optimized for the moons of Uranus.

4 x 30 sec clear filter, taken at 08:47 UT

2) The upper right image is the output from the Uranus Viewer 1.1 web site showing the positions of the moons. The web site is at:

http://ringside.arc.nasa.gov/www/tools/viewer_ura.html

3) The lower left image is an LRGB taken at 08:36 UT. This image was optimized for the disk of Uranus.

L = 11 x 5.5 sec

R = 3 x 10 sec

G = 3 x 10 sec

B = 3 x 10 sec

4) The Lower right image is a composite made from images the 1) and 3) showing the Uranus disk and the moons in one image.

From: egrafton@ghg.net (Ed Grafton)

Hi Frank, Thanks for the congratulations! I tried a couple of configuration last night to see what would yield the best results for capturing Miranda. There is a background star to the lower left of Titania. As you can see from the image below, the background star moves relative to Uranus and its moons in the 44 minutes between the two images. You can also see that Miranda is tracking along with Uranus so it cannot be a background star.

http://www.ghg.net/egrafton/miranda.jpg

At 02:51 PM 7/19/02 EDT, FrankJ12@aol.com wrote:

>Dear Ed-

> Did you check to make sure it is not a background star? Did you find Miranda's position at the time of the image was taken?

> It seems that you really have captured Miranda! It should be in the right place with respect to Uranus. And it is the faintest of the five satellites. I am congratulating you for being as a first amateur astronomer to capture Miranda. I knew you are the one who will do this!

> Keep imaging while you can just to make sure that a little speck of light is still there around Uranus.

> Keep it up with your great work of imaging Uranus itself and its satellites!!

> Reagrds,

Frank J MELILLO

Ed GRAFTON (Houston, Texas, USA)

egrafton@ghgcorp.com

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