IPB

Welcome Guest ( Log In | Register )

 
Reply to this topicStart new topic
Pioneer's Jovian Moons Images., Questions
Decepticon
post Jan 21 2006, 08:05 PM
Post #1


Senior Member
****

Group: Members
Posts: 1155
Joined: 25-November 04
Member No.: 114



I found it odd that most astronomy books that I read never mentioned that they where imaged.
Here are some images from the book.
http://history.nasa.gov/SP-349/ch6.htm (Figure 6-5)

1. What hemispheres where imaged by the Pioneer's?

2. Has anyone used current moons maps to create what Pioneer could of imaged if it had better imaging capabilities?

3. If Pioneer 11 imaged IO what area could have been seen? (I understand Pioneer experience radiation exposure and caused a failed imaging attempted?)

4. Any why does Ganymede look so odd in the above link?(Figure 6-5)
Go to the top of the page
 
+Quote Post
Guest_PhilCo126_*
post Jan 21 2006, 08:16 PM
Post #2





Guests






Well, Pioneer 10 was surely battered by the radiation at Jupiter sad.gif
I suppose those photos of the Jovian moons are the 'corrected' versions, as the raw Pioneer images were heavily distorted and computer programs were used to clear out those images..
I don't know if Io was imaged by Pioneer huh.gif
Go to the top of the page
 
+Quote Post
JRehling
post Jan 21 2006, 08:27 PM
Post #3


Senior Member
****

Group: Members
Posts: 1569
Joined: 20-April 05
Member No.: 321



QUOTE (Decepticon @ Jan 21 2006, 12:05 PM)
4. Any why does Ganymede look so odd in the above link?(Figure 6-5)
*


This display seriously oversamples the data, which was not obtained with a ccd grid, but rather sampled from a rotating pushbroom. Some combination of pointing error or mapping of the camera output causes a wavy distortion. Also, I think the imaging system may have been optimized for the bright cloudtops of Jupiter, making Ganymede a bit dark as a target. That said, if you downsample this image to about 1/7 or so the size in which it is presented, it shows us the image for what it is worth: Ganymede at about 150 to 200 km/pixel, and as such, there's nothing else odd about it. It's impressive that the text presented a valid interpretation of the polar frosts given such limited data. Incidentally, this is about the resolution now achieved by HST.
Go to the top of the page
 
+Quote Post
JRehling
post Jan 21 2006, 08:29 PM
Post #4


Senior Member
****

Group: Members
Posts: 1569
Joined: 20-April 05
Member No.: 321



Pioneer 11's image of Io is here:

http://www.solarviews.com/cap/jup/pio.htm
Go to the top of the page
 
+Quote Post
ljk4-1
post Jan 21 2006, 09:19 PM
Post #5


Senior Member
****

Group: Members
Posts: 2454
Joined: 8-July 05
From: NGC 5907
Member No.: 430



QUOTE (Decepticon @ Jan 21 2006, 03:05 PM)
I found it odd that most astronomy books that I read never mentioned that they where imaged.
Here are some images from the book.
http://history.nasa.gov/SP-349/ch6.htm  (Figure 6-5)

1. What hemispheres where imaged by the Pioneer's?

2. Has anyone used current moons maps to create what Pioneer could of imaged  if it had better imaging capabilities?

3. If Pioneer 11 imaged IO what area could have been seen? (I understand Pioneer experience radiation exposure and caused a failed imaging attempted?)

4. Any why does Ganymede look so odd in the above link?(Figure 6-5)
*


Here are the "best" photos taken by the Pioneers of the Galilean moons.

http://history.nasa.gov/SP-349/p180.htm

In Murmurs of Earth (1978), Carl Sagan speculated that Io may be covered in salts, as it did not display an ice signature like the other moons. One of the main Voyager team scientists also said just before the Voyager 1 flyby in 1979 that they hoped and assumed that Io would be the "Rosetta Stone" for understanding the Jovian system. They were rather surprised and disappointed at first when they didn't see any obvious craters. Then they got another surprise.

I can remember when the showed the images of Ganymede from Pioneer 10 in Sky & Telescope in 1974 and trying my darndest to discern anything recognizable from the images.


--------------------
"After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance.
I see that such intercourse long continued would make one thoroughly prosaic, hard,
and coarse. But the longest intercourse with Nature, though in her rudest moods, does
not thus harden and make coarse. A hard, sensible man whom we liken to a rock is
indeed much harder than a rock. From hard, coarse, insensible men with whom I have
no sympathy, I go to commune with the rocks, whose hearts are comparatively soft."

- Henry David Thoreau, November 15, 1853

Go to the top of the page
 
+Quote Post
tasp
post Jan 21 2006, 09:44 PM
Post #6


Member
***

Group: Members
Posts: 885
Joined: 30-January 05
Member No.: 162



IIRC, Pioneer made what would have been a nice 25,000 km flyby of Amalthea, if only it had a Voyager camera.

{yeah, don't remind me what Galileo did, arg!}
Go to the top of the page
 
+Quote Post
tedstryk
post Jan 21 2006, 11:48 PM
Post #7


Interplanetary Dumpster Diver
****

Group: Moderator
Posts: 4197
Joined: 17-February 04
From: Powell, TN
Member No.: 33



Here are some attempts I made to improve Pioneer images of the Galileans and Titan a while back.



Also, here is a version of the Io image from the original digital data (the only one of the satellite images for which, to my knowlege, a full digital set still exists).



--------------------
Go to the top of the page
 
+Quote Post
Decepticon
post Jan 22 2006, 07:39 AM
Post #8


Senior Member
****

Group: Members
Posts: 1155
Joined: 25-November 04
Member No.: 114



QUOTE (tasp @ Jan 21 2006, 04:44 PM)
IIRC, Pioneer made what would have been a nice 25,000 km flyby of Amalthea, if only it had a Voyager camera.

{yeah, don't remind me what Galileo did, arg!}
*


Aggravating ehh!?

tedstryk Wonderful work. When my son is old enough this sample you posted will be used to show him.

I want my son to experience everything I did. And so far The Moon and Stars do have his attention at night!

This thread has great links and pics, Thanks everyone!
Go to the top of the page
 
+Quote Post
t_oner
post Jan 22 2006, 05:33 PM
Post #9


Junior Member
**

Group: Members
Posts: 94
Joined: 26-September 05
Member No.: 508



Here is a scan of the best print I have ever seen of the Galilean satellites from Pioneer, from Nasa SP-439 Voyage to Jupiter. I have B&W copy of another picture of Callisto which is nearly as good as the above image showing a larger portion of the disk. I will post, if I can find it.
Attached thumbnail(s)
Attached Image
 
Go to the top of the page
 
+Quote Post
Decepticon
post Jan 22 2006, 06:57 PM
Post #10


Senior Member
****

Group: Members
Posts: 1155
Joined: 25-November 04
Member No.: 114



WOW Great stuff! ^^^

Looking forward to Callisto!
Go to the top of the page
 
+Quote Post
t_oner
post Feb 5 2006, 11:43 AM
Post #11


Junior Member
**

Group: Members
Posts: 94
Joined: 26-September 05
Member No.: 508



Here is the Callisto image I promised. I know it doesn't look great but this is an image not seen very often. smile.gif
Attached thumbnail(s)
Attached Image
 
Go to the top of the page
 
+Quote Post

Reply to this topicStart new topic

 



RSS Lo-Fi Version Time is now: 30th July 2014 - 12:59 AM
RULES AND GUIDELINES
Please read the Forum Rules and Guidelines before posting.

IMAGE COPYRIGHT
Images posted on UnmannedSpaceflight.com may be copyrighted. Do not reproduce without permission. Read here for further information on space images and copyright.

OPINIONS AND MODERATION
Opinions expressed on UnmannedSpaceflight.com are those of the individual posters and do not necessarily reflect the opinions of UnmannedSpaceflight.com or The Planetary Society. The all-volunteer UnmannedSpaceflight.com moderation team is wholly independent of The Planetary Society. The Planetary Society has no influence over decisions made by the UnmannedSpaceflight.com moderators.
SUPPORT THE FORUM
Unmannedspaceflight.com is a project of the Planetary Society and is funded by donations from visitors and members. Help keep this forum up and running by contributing here.