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Sept 6/2005 APOD

Posted: Tue Sep 06, 2005 6:55 am
by makc
APOD[/url] [url=http://saturn.jpl.nasa.gov/news/press-release-details.cfm?newsID=598]Cassini aug 30 pressrelease wrote:...the moon's southern pole is active. The pole had episodes of geologic activity as recently as 10 years ago. ...When NASA's Voyager 2 spacecraft flew over the moon's north pole in 1981, it did not observe the tiger stripes.
So, did its surface changed since '81, or stripes simply were not visible? Where can I take a look at those '81 photos?

Posted: Tue Sep 06, 2005 9:29 pm
by BMAONE23

Posted: Wed Sep 07, 2005 6:41 am
by makc
thanks. we have:
Voyager vs Cassini

Image

indeed, they are not there! in composite image above you can see how much did it changed for 20 years. I've marked details that seem to be same on both images.

Posted: Wed Sep 07, 2005 2:01 pm
by orin stepanek
The icy asteroids might suggest an abundance of water in the solar system. Could the tiger stripes suggest liquid might be present under the frozen surface?
Orin

Posted: Wed Sep 07, 2005 4:16 pm
by Odegard
Wow, makc, nice work! May I use that picture on my site for a newsitem?

How would you like to be reffered to? I guess we need to put NASA in there somewhere...

-Odegard

Posted: Wed Sep 07, 2005 5:03 pm
by makc
everybody can use it anywhere - nasa images are in public domain. if you really insist, use my e-mail makc.the.great@gmail.com, but you don't have to.

EDIT: now, when I've looked at it 2nd time... so many details do not fit... maybe these "matching" patterns are simply my imagination?

Posted: Thu Sep 08, 2005 2:51 am
by craterchains
Sorry Makc, I can't see any reference points that match up to be able to check for changes. Over the past three years I have done allot of crater comparisons and searching images for changes on Mars. There are many, but you have to first get a reference point that matches up in both images, like sets of craters, or ridges that are easily identifiable in
both images. then look for changes. Lat. and Long are a big help ,,,,,, when they bother giving those details.

QUOTE
EDIT: now, when I've looked at it 2nd time... so many details do not fit... maybe these "matching" patterns are simply my imagination?

Patterns may be different, but until we have a known view of the same area, we won't know for sure. I am now looking at a bunch of pics trying to find one that shows the same area. None ,,,,,,, yet.

I take it that you can't just transfer posts in this BB? Bummers.
Norval

Posted: Thu Sep 08, 2005 12:53 pm
by crosscountry
craterchains wrote:Sorry Makc, I can't see any reference points that match up to be able to check for changes. Over the past three years I have done allot of crater comparisons and searching images for changes on Mars. There are many, but you have to first get a reference point that matches up in both images, like sets of craters, or ridges that are easily identifiable in
both images. then look for changes. Lat. and Long are a big help ,,,,,, when they bother giving those details.

QUOTE
EDIT: now, when I've looked at it 2nd time... so many details do not fit... maybe these "matching" patterns are simply my imagination?

Patterns may be different, but until we have a known view of the same area, we won't know for sure. I am now looking at a bunch of pics trying to find one that shows the same area. None ,,,,,,, yet.

I take it that you can't just transfer posts in this BB? Bummers.
Norval
maybe they changed too? just a little?

Posted: Sat Sep 10, 2005 1:01 pm
by craterchains
Crosscountry, "maybe they changed too? just a little?".
Yes, that is a very distinct possibility. But, we still need reference points before we can determine any changes. Scientists seem to have them, but aren't sharing. :?

Makc, I'd say lock the other thread and do your post transfer thingy. :)
Norval

Posted: Sat Sep 10, 2005 4:41 pm
by BMAONE23
The images from the Voyager 2 probe passed over the North Pole of the moon. If you look at the cassini images of the polar regions you will see the crater paterns you are looking for. I do not believe that there are any Voyager images of the south polar region, at least none that I have been able to find.

Posted: Sat Sep 10, 2005 4:48 pm
by BMAONE23
in the Voyager image the North Pole sits in the lower right quadrant of the image at the ternimator between day and night. In the Cassini image the South Pole sits in the middle of the "Tiger Stripes"

Posted: Mon Sep 12, 2005 6:25 am
by makc
I'm affraid BMAONE is right. Here's what he said in PM (why PM, anyway ?):
It would appear that the older voyager image is of the north polar region.

Look at:
http://www.nasa.gov/mission_pages/cassi ... 07721.html
And compare it to
http://Voyager.jpl.nasa.gov/image/image ... celadx.gif
.

Now,
Makc, I'd say lock the other thread and do your post transfer thingy.
Norval
since this thread (my question) is now resolved, I will lock it instead :wink: