Exquisite Saturn Images Options

[tedstryk]

Here are some HST images I recently worked on. I have also posted some of my work on HST Galilean imagery in this thread.

This view is from March 7, 2003 using a mosaic of ACS HRC Images. The rings were clipped except for one image on the left side, which I used to extend both sides beyond the edges of the original image, along with WFPC/2 images taken within about an hour of the set.



Also, I have reprocessed the old August 26, 1990 view. It is relatively limited (there were only three filters used, and it was taken using the wide field chips, not the planetary camera). Still, it is (at least to my knowledge, Hubble's first look at a planet.

[jasedm]

Fantastic! - how Galileo would have loved these!!!!!

[tedstryk]

I started to ask you what in the world you were talking about....then I realized you were talking about Galileo Galilei, not the Jupiter orbiter!

[tedstryk]

Here is a more primitive processing of the data (without the ring reconstruction and enhancements to bring out more detail).



Also, today's Cassini release is neat...It has a real Pioneer-ish feel.

[Bjorn Jonsson]

Here are some HST images I recently worked on. I have also posted some of my work on HST Galilean imagery in this thread.

This view is from March 7, 2003 using a mosaic of ACS HRC Images. The rings were clipped except for one image on the left side, which I used to extend both sides beyond the edges of the original image, along with WFPC/2 images taken within about an hour of the set.

Interestingly one can see Saturn's blue winter hemisphere through the Cassini Division and this is a pre-Cassini image. I have always found it strange that as far as I know the blue color was an unknown phenomenon before Cassini imaged it. This is remarkable - I have even managed to image it using a 6" telescope and a webcam after the northern hemisphere became visible from Earth due to the decreasing ring opening angle. I also think that observing visually I have seen hints of the color but it should be noted that I wouldn't have noticed it without knowing it was there .

[tedstryk]

Interestingly one can see Saturn's blue winter hemisphere through the Cassini Division and this is a pre-Cassini image. I have always found it strange that as far as I know the blue color was an unknown phenomenon before Cassini imaged it. This is remarkable - I have even managed to image it using a 6" telescope and a webcam after the northern hemisphere became visible from Earth due to the decreasing ring opening angle. I also think that observing visually I have seen hints of the color but it should be noted that I wouldn't have noticed it without knowing it was there .

I am guessing here (I haven't worked on the issue myself), but maybe this effect is lost with Voyager's OGV, GVUV, and whatever else color shifts.

[ugordan]

I am guessing here (I haven't worked on the issue myself), but maybe this effect is lost with Voyager's OGV, GVUV, and whatever else color shifts.

It should have been more than readily apparent in the violet filter. The reason it was absent was probably the proximity of equinox. Saturn's northern color is fading again as ring shadows move towards the south.

[tedstryk]

It should have been more than readily apparent in the violet filter. The reason it was absent was probably the proximity of equinox. Saturn's northern color is fading again as ring shadows move towards the south.

Yes, but with color shifting, it would have looked green or yellow.

[scalbers]

Bjorn - yes that is funny about how such an interesting discovery can be hiding in plain sight. I think I could also see this in my friend's earthbound CCD imagery from a few years back. I'll have to try this visually in a telescope, though another good opportunity might have to wait a long time?

So is Saturn a part-time local Neptune?

[tedstryk]

Not-so-plain sight. As Ugordan pointed out, it is fading as equinox approaches. Pioneer 11 was just before equinox, and Voyagers 1 and 2 were not too long after. From Earth, the rings obscure the winter hemisphere. Since the rings are brighter than the disk, it makes the bits of the blue area one can see through and behind the rings visible in low resolution images hard to notice.

[ugordan]

Since the rings are brighter than the disk, it makes the bits of the blue area one can see through and behind the rings visible in low resolution images hard to notice.

It should be noted the rings only appear brighter than the planet at low phase angles (as seen from Earth). They grow dimmer with increasing phase angle and their "dirty" nature becomes more apparent as brownish coloration.

In any case, it shouldn't be that surprising Saturn would acquire a bluish hue when the sunlight is significantly reduced - both Uranus and Neptune share a similar color. It remains questionable, however, just how much Saturn cloud activity is driven by internal heat.

[tedstryk]

It should be noted the rings only appear brighter than the planet at low phase angles (as seen from Earth).

That is true. Still, during either hemisphere's deep winter, they are always illuminated at a low phase angle.

[Floyd]

They are looking for new moons again. I took an a plastic sheet and a marking pen and found 5 moving objects against the stars in the first 3 pages of images. My prblem is that I don't really know to figure out what I am finding using any of the programs out there. I'm sure sure some of you here might be able to "co-discover" something new in this recent batch of images. Also would make great movies
-Floyd

[ngunn]

I'm not usually a rings person especially but this is an exceptional image, I think:

http://ciclops.org/view.php?id=3885

[Ian R]

This is quite a decent WAC view of Saturn that I've quickly put together: