"Jan Panteltje" <pNaonStpealmtje@yahoo.com> wrote in message
news:1113045716.312ae5e87dcb51bc2db06841582f4407@teranews...

I would like to know the exact speed:
SPACECRAFT_CLOCK_START_COUNT = "1/0022263021.32357"
SPACECRAFT_CLOCK_STOP_COUNT = "1/0022263684.65219"

Making the picture took 3684.65219 - 3021.32357 = 663.32862 seconds.
In that time 27320 lines of pixels were scanned.
So per pixel line: 663.32862 / 27320 = .024799 S = 24.8 mS

So available exposure time of 24.8 mS for a row of pixels...

I found on a web site that the camera samples at 400 to 800 Hz.
that is 2.5 to 1.25 mS

I'd say the images are 'under exposed' by a factor 10 to 19.
See the numbers in my other post.

Just an off-the-cuff comment, how much time
between exposures is needed to read the data
out of the elements? I have no idea in this
case but in some other work I've done, it was
significant.

I would like to know the exact speed:
SPACECRAFT_CLOCK_START_COUNT = "1/0022263021.32357"
SPACECRAFT_CLOCK_STOP_COUNT = "1/0022263684.65219"

Making the picture took 3684.65219 - 3021.32357 = 663.32862 seconds.
In that time 27320 lines of pixels were scanned.
So per pixel line: 663.32862 / 27320 = .024799 S = 24.8 mS

So available exposure time of 24.8 mS for a row of pixels...

I found on a web site that the camera samples at 400 to 800 Hz.
that is 2.5 to 1.25 mS

I'd say the images are 'under exposed' by a factor 10 to 19.
See the numbers in my other post.

Recommendation:
If software in the camera can be re-programmed, decrease the 400 Hz.
(increase exposure time).

For Y we have max 106 steps.
Increasing exposure by 19 would give 2014 steps.
The AD is 14 bits on a '12 bit (they say)' CCD.
2 ^12 = 4096

2014 grey levels fits nicely in that.

Some assumptions were made:
All time in spacecraft clock was used for imaging.

The soft in the camera caused the big 'set up level' by increasing gain,
to get a signal (see other post).
The numbers from 400-800 Hz are correct for this camera.
I did not goof up big time.

Jarmo what do you think?

In alt.sci.planetary
<mjones-B63267.23265005042005@spectator.sj.sys.us.xo.net> stated that:

It doesn't have to mimic the light absorption in water.

***{It does in order to support your case. You claim that geology could
produce these results, and yet *none* of the photographs of Earth
geology you cited had the characteristics which a geological explanation
would require. --MJ}***

*sigh* I said I wouldn't bother. But here I go again :) The reason is that
"gocha" down below. And other absurd stuff I find in this post.

There just
has to be one darker, slightly bluer (muddy? salty?) sediment layer
on top (or underlying, as I explained earlier) of a brighter, slightly
yellower (sandy?) unit. And then we diffuse the contact. Are you
following? Now, let's image this region with three color channels:
r, g and b. In red the area seems dark, compared to the surroundings.
In green the area seems dark compared to the surroundings. And, in
blue, the area seems dark, compared to the surroundings. Now, as we
'fiddle around' with these colors, and make a color image, we can make
any adjustments (as I showed you in the rgb images I provided you with).
My point (you can't have missed it) is that the colors, especially in
that PR rgb image, are _not_ _calibrated_ _so_ _you_ _can_ _make_ _no_
_assumptions_ _on_ _the_ _spectral_ _characteristics_ _of_ _the_ _area_,
unfortunately.

***{Now you are sliding back into the "false color" explanation. But
those are two different lines of argument. You can say that the color
pattern in that photo mimics the pattern of spectral absorption in water
(a) because the camera is inaccurate in a systematic way that happened
to progressively delete more and more of the long wavelengths as the
depth increased, or (b) because the rock layers themselves, as we go
progressively deeper and deeper, absorb progressively more of the longer
wavelengths.

So a combination of those is not acceptable? Why not?

"it's not an image of a green cat, the colors are wrong" and "it's not a
cat, it's a dog", but not "the colors are wrong, it's not a green cat,
it's a dog"?!?!?!?!

<example>

Forget Reull Vallis for a couple of minutes.

Let's suppose: there are layers on the ground. Whatever layers, darker
than the surroundings. Three spots - in real life - show the the
following intensities in three wavelength channels, when 1 is on the
surrounding brighter area, 2 on the transition and 3 in the dark
area. "|" is high intensity and "." is low intensity of that
particular brightness level. We get

dark <--> bright
1:
R: .......|.
G: ..|......
B: ..|......
2:
R: .....|...
G: .|.......
B: .|.......
3:
R: ...|.....
G: |........
B: |........
->
red shifts two intervals from spot to spot
green shifts one interval from spot to spot
blue shifts one interval from spot to spot

In each channel the third spot is the darkest, of course. However,
all areas in real life are red(dish) in color, right? Red dominates,
we can maybe say. But green and blue travel hand in hand.


Now, let's image the area with a camera, the calibration of which
has gone haywire. Now, from the three locations we get the following
intensities, if the _sensitivity_ of the three different sensors
is different. Just supposing. Not necessarily the case in Reull.
Dunno. But just supposing. In principle. Capish? Forget Reull.

dark ..... bright
1:
R: .......|.
G: ......|..
B: ....|....
2:
R: ...|.....
G: ....|....
B: ...|.....
3:
R: .|.......
G: ..|......
B: ..|......
->
red shifts three intervals from spot to spot in the image
green shifts two intervals from spot to spot in the image
blue shifts one interval from spot to spot in the image

So, comparing the three sites we can see that all channels are reduced
in intensity when going from 1 to 2 to 3. Red mostly, then green, and
blue the least. This makes spot 1 seem red, spot 2 slightly green and
spot 3 blue-green. This could basically be because the surface reflects
like you say it does - like light being absorbed in deepening water.
But, as we see in the above "real life" sample, this is not the case.
What is happening here, is that a) red channel is a bit more sensitive
to brightness variations than plain eye, b) green also, slightly less
so, and additionally it is shifted towards the bright a bit, and c) blue
sensor responds to the shifting as an eye would, but is shifted towards
the bright a bit.

</example>

Jan, Mitchell, anybody, please explain why this can not be, just in
principle? In my opinion, it is quite possible.

Okay, if this - for some strange reason - could be, then why can't the
colors in the Reull Vallis be as screwed up? Why couldn't a slightly
green-blue very dark area appear as deep-dark-blue while a reddish area
stays the same, at the same time? It is quite weird to me that you will
not even consider this. Please respond with some other answer than
"it is absurd, can't you see the color change! it's there!"

I asked you to cite examples of Earth geology in which
layering followed the pattern of (b), and you failed to do so. But when
I point out that you failed, you say the examples didn't have to
illustrate (b), because of (a)! Well, that's irrelevant: I asked you for
examples of (b), not (a). Moreover, I knew you couldn't cite such
examples, because no such examples exist, for the reasons that I stated
at the time.

I show you layers. Lots of different colored layers. Imaging these layers
with uncalibrated image channels may be the key here.

This image shows the same color patterns as the Reull Vallis PR image.
What do you say about it then? Yes, that is a depression you see down
on the left. Is this a lake? Why / why not? The image width is ~10 km
or so. And I assure you, it is a real HRSC RGB image.
http://www.student.oulu.fi/~jkorteni/tmp/reullvallis/whatisthis.jpg

***{It doesn't affect it at all, obviously, because the inferences you
are drawing do not follow from the evidence you are citing. I would
never have expected or demanded that component images, unassembled,
should even be recognizable, much less that they ought to demonstrate
that the final, assembled and processed image, is incorrect. --MJ}***

Err...?

http://www.student.oulu.fi/~jkorteni/tmp/reullvallis/mola_topography.jpg

***{That's just that same topo you cited before, which was obviously
measured with the laser sloping downward at an angle from south to
north, rather than pointing straight down. Result: it could not see into
the crack, when the crack was narrow. Isn't that obvious? Think about
it: if a crack is a mile deep and ten miles wide, a laser sweeping in
from an angle can hit the bottom; but if the crack is only an inch wide
and a mile deep, the laser has to be directly overhead. --MJ}***

Read my other post about MOLA.

Damn, you really have no idea what you
are talking about.

http://www.student.oulu.fi/~jkorteni/tmp/reullvallis/rgb_mola.jpg
The first one is just for reference. Now, in the latter you can see
stuff superposed on the HRSC rgb image. The deepest areas in the valley
are shown in black, dark colors, outlined by red

***{No they aren't. Ever heard of "pulse broadening"? What it means is
that the MOLA laser starts out with about the width of a soda straw,
and, by the time it reaches the surface of the lake, scattering due to
passage through the air will make the beam about 130 meters in diameter.
Now while IR as a general rule is much more strongly absorbed by water
than is visible light, there are specific wavelengths to which water is
quite transparent, and the best of them is the short-wavelength near
infrared region, 700 to 1330 nm. The center of that region, where the
optical density of water is comparable to that of short wavelength
visible light, falls exactly at the 1064 nm wavelength used by the MOLA
laser. [See, for example, http://www.dartmouth.edu/~etrnsfer/water.htm
for details.] What I am saying is that the MOLA laser is 130 meters in
diameter when it passes into the water, due to pulse broadening that has
taken place during its passage through the atmosphere, and that the
scattering, hence the broadening, increases enormously after it is in
the water. Result: the fantastically sensitive electronics aboard Mars
Global Surveyor outdid itself, and detected long-delay pulses from over
a much more widely distributed area, due to the presence of the water,
than would have been possible if the water had not been there. Indeed,
every detail of the pattern you cited is predictable, based on the
behavior of electromagnetic rays passing through water. For example, the
falsely enlarged area produced by the hole at the left which you labeled
1 has spread down and to the left (a) because the steep side of the hole
is at the upper right, and the walls on that side have acted to inhibit
scattering in that direction, and (b) because any returning photons
scattered in that direction are, obviously, headed *away* from the
camera. Similar considerations explain the other discrepancies you have
listed. (But none explain why you used the number "1" twice. :-)

No offence, but your creditability just went down to an even more lower
level. Didn't think it could. Gongrats.

Bottom line: this is just more evidence that what we are seeing is, in
fact, a lake. It is obvious from inspection of the optical photos that
much of what shows to be deep on the topo is in fact shallow. But the
pulse broadening due to passage through the air only expands the beam
width to 130 meters. Thus there is no way it could spread the topo plot
out like what we see. Only passage of the beam into liquid water could
do that. For only then could scattering spread out the plot to the size
that we actually see.

Oh no, it's not the bottom line! (i.e.: there's more..)

http://www.student.oulu.fi/~jkorteni/tmp/reullvallis/mola_topography+10000
.tif

The grayscale values correspond to actual surface height in meters,
relative
to mean planetary radius (similar to our sea level), with a constant
value of 10000 added to every value, to overcome some software
limitations
you might have (most programs do not correctly read signed 16-bit data).
In other words, a grayscale value of 5000 corresponds to an elevation of
-5000 m, 0 to -10000 m and 7389 to -2611 meters.

***{As I pointed out in an earlier post, the contours of the lake bottom
are as indicated in the ESA color photo, because that is confired by the
black and white NASA photos which I cited. The clash between the topo
and what is obvious by inspection of the photos is due to the fact that
the topo is a computer generated plot of laser reflections. Those
reflections misrepresent the surface for several reasons:

Drums.

(1) The beam descends at an angle, and can't probe the bottoms of
narrow, east-west running declivities.

You really don't know... do you really believe this yourself?

You're
right. MOLA does not peek into cavities, no.. but the cavities in question
have to be much smaller than the footprint to not be detected.

Footprint
is always smaller than 150 meters.

And the DTM uses a scale of 463 meters
per pixel, which is well above that limit. And MOLA is designed to operate
vertically, not at a noticeable angle.

(2) The beam is affected by pulse broadening, which is especially
pronounced when the lower end of the beam is passing through water.

Yes yes. Of course it is.

(3) The intensity of the laser and the fantastic sensitivity of the
electronics that monitors for the return beam ensures that even low
intensity returns that have been delayed by scattering in water will be
detected.

Yup. Must be right.

***{No superfluid is required. The topo is in error for the reasons
explained above. Moreover, those distortions require an extent of pulse
broadening that could not happen, if the beam had only passed through
air. Evidently those who designed the instrument did not expect the beam
to pass through water because, like you, they were utterly certain there
was no liquid water on Mars. Well, live and learn! :-) --MJ}***

I am actually looking forward to your next statement... :)

***{That's another ad hominem remark. Things work better in a discussion
if such comments are avoided. As to whether my comment was wrong, it
wasn't, as you will discover below. Unfortunately, by shooting from the
hip again, you have charged off down another time-consuming and
irrelevant tangent, as you have done several times in the past. :-(
--MJ}***

You know what? I do enjoy it when someone uses reason in a discussion, and
I have to prove that I am right.

Sometimes I am not, and I admit it.
Sometimes the other person is so convincing that I have to admit that
there is a possibility that I am wrong. But, in this case, you started off
like somebody who might have a point, but lately your remarks have become..
well, shouldn't use any ad hominems...

1.39 meters / pixel:
http://www.msss.com/moc_gallery/m07_m12/images/M07/M0700184.html

2.78 m/pixel:
http://www.msss.com/moc_gallery/ab1_m04/images/M0200301.html

5.55 m/pixel:
http://www.msss.com/moc_gallery/ab1_m04/images/M0403117.html

***{I was speaking of wavelength resolution, not pixel width. Black and
white photos, by definition, can never have the wavelength resolution of
a color photo. And it is the implications of the higher wavelength
resolution of the ESA Reull Vallis photo that have formed the basis of
this entire discussion. --MJ}***

Well then say wavelength resolution.

And those are gray-scale images,
not black and white. *sigh*

Of course they can never have the wavelength
resolution. BUT WHAT ABOUT THE DETAILS SEEN IN THE IMAGES? (sorry for
shouting but you seem to _not_hear_me_.

Oh, sorry, here's the reply, my
bad.

These are images traversing the east-west -portion of the valley floor.
In other words, as I understand, they are not in the area of interest.
Well, in fact they are, since they exhibit similar deposits to those
seen in the "lake". But, hey, no water-resembling stuff here, either.

***{A black and white photo has essentially zero wavelength resolution.
Result: most of the cues that alerted me to the fact that this is a lake
are not present in a black and white photo. I say "most," not "all." The
shoreline remains apparent, and there is a dimming of the light levels
reflected from the lake bottom, even in areas in full sunlight, which
suggests attenuation due to passage through a medium. The color photo,
of course, is vastly superior to the black and white photos, just as
color vision is vastly superior to color blindness. --MJ}***

Hmm.. so you prefer the color photo of a plane from 2 km to the "black and
white" image taken at 50 meters? Especially in the case where you are
saying "the plane is American Airlines, I'm sure of it"?

Please compare these to the HRSC nadir image, the best resolution image
obtained by HRSC from that region. Below are cut-outs if your browser
does not allow to browse through the gigantic image.

http://www.student.oulu.fi/~jkorteni/tmp/reullvallis/nadir_cut_1.jpg
This is from the eastern curve dark deposits. In it you can see definite
surface texture inside the region of the lake. Through my trained
planetary geologist eyes, we see impact craters, and a dark field,
probably consisting of dunes.

***{As I said in an earlier post, these extreme blow-ups are far to
grainy to indicate much of anything. The question is whether these areas
are or are not underwater. If they are then the range of permissible
interpretations does not include, for example, "dune fields." --MJ}***

Yes. Strange, I can make out quite a bit of surface features in all of
the images. How long have you been a planetary image interpreter?

http://www.student.oulu.fi/~jkorteni/tmp/reullvallis/nadir_cut_2.jpg
This is the east-west ridge-occupying dark deposit. You can see clear
viscose flow-marks in it.

***{Streamlines converge as liquid flows downhill, so those parallel,
downhill running marks are *not* flow marks. They are, instead, marks
made on the sides of the declivity by immense objects rolling downhill.
But where are those objects? The answer, they are buried in the silt at
the bottom of the declivity, awaiting the next violent upward thrust of
water out of the hydrothermal vent. When that upward rush of water
occurs, those immense boulders will be carried upward with it, then to
the side as the flow spreads out at the surface, and will then roll back
down the hill and into the declivity again. There, they will be caught
by the current and carried upward again. Each time the boulders roll
downhill, they will leave a track, and they will keep doing that until
the episodic flooding event is over, after which they will settle back
into the crack and be silted over again, awaiting the next episode of
flooding. --MJ}***

This is interesting. I really don't know what those markings are. They
appear in several regions, at the floors of fluvial channels. We suspect
that they are probably slides of mud, originally freezed after the
flow and later re-warming and becoming mobile.

Please can you exxplain why is it there? Here's an example from a MOC image
of 2.92 m/pixel:

http://www.student.oulu.fi/~jkorteni/tmp/reullvallis/moc.jpg

***{As I explained above, your interpretation of the topographical map
is incorrect. --MJ}***

Sure it is.

***{I stand by those statements. It is you who needs to rethink his
position. You have built your entire case on the laser altimeter
readings, and, for the reasons I explained above, that makes your
position a house of cards. --MJ}***

*thinks*... nah, I think I'll stand by my statements too. It's more fun
that way.

It would seem that my theory made a testable prediction, and that
prediction proved to be true, now didn't it? :-)

Nope.

***{Yep. --MJ}***

Nah...

How do you propose it got there? Usually, actually, always, to my
experience,
a hydrothermal vent is restricted to regions of volcanic and/or major
tectonic
activity. As there is no volcanism, or graben-forming extensive
tectonism...

***{Reull Vallis sits on the lip of the Hellas impact basin, which
happens to be the largest and deepest crater on Mars. It is 9 km deep
even today, after more than a billion years of debris accumulation. At
the bottom of that accumulation, several km further down, lots of
geothermal heat is going to be available. Result: as water trickles down
through that debris, it gets hotter and hotter, and eventually flashes
to steam. Where is that steam released? Well, I should think it would
flow through whatever vertical cracks it might find in the crater walls,
until it reached the surface, where it would blow out of a vent. As
hundreds of millions of years passed and the floor of the impact basin
filled more and more deeply with sediment, those vent holes would
migrate upward, because sediment could never fill up an active
hydrothermal vent. The result is what you see today in Reull Vallis,
and, doubtlessly, in similar circumstances all around the edge of the
Hellas impact basin. --MJ}***

Okay.. supposing you are right, why is this area still active, but not
for example the volcanoes?

***{My point is that there is plenty of water to feed hydrothermal
vents. I take it that you agree. --MJ}***

Yes. Plenty of water on Mars. Was. Maybe still is. Reull Vallis is one
heck of an example itself. It's a flow channel.

***{Yup. And here's why: after the Hellas impactor crashed into Mars,
the resulting crater begain to accumulate dust, debris, and water. And
when that water got close enough to the recently exposed magma, it
flashed to steam, and was vented to the surface. And, with the passage
of hundreds of millions of years, those vent holes remained open,
because any sediment that accumulated there was periodically blown out
of the pipe when venting occurred. Thus as the crater filled up, the
vent holes simply migrated upward, and, due to cooling, came to vent
liquid water rather than steam.

Okay. Basically not a bad idea. Several of your ideas are good in principle.
But, for some strange reason you've decided to convince the world that all
of your ideas apply here. Sorry to burst your bubble.

What this all means is simple: there are going to be hydrothermal
vents
on Mars, and some of them will be in low lying areas. Result: there
will
be pools of liquid water at those locations. To suppose otherwise
would
be to suppose a miracle.

The only problem you have is to show the existence of geothermal
vents in
the area.

***{It's there in the photo, plain as the nose on your face. --MJ}***

In the photo is a dark deposit, on a slope.

***{I repeat: it's not on a slope. Your interpretation of the laser
altimeter results is wrong. --MJ}***

Sorry. Forgot.

Is it still so? If it is, then I admit, I couldn't convince you with the
geomorphological images. You say that there is a possibility that this
dark deposit is a lake, and since it is a possibility, then it must be
so, regardless of the facts given to you.. fine. I rest my case. Couldn't
convince you. Too bad.

***{I'm hard to convince with unsound arguments, 'tis true. :-) --MJ}***

Blah.

***{I don't know about volcanism, but the existence of the lake--which
is proven--requires a geothermal heat source. Otherwise the water would
freeze. --MJ}***

Yes, it indeed does require a heat source. And my point was.. nah, forget
it.

***{Your point was that no such heat source is available in Reull
Vallis. But, as I said, it's on the lip of the Hellas impact basin,
which would logically be rimmed with hydrothermal vents, due to the
operation of the geological process that I described. Is that not a
sufficient answer to your question? :-) --MJ}***

There are two major volcanic centers near Hellas, Malea and Hesperia Planum.
Both have extensive volcanism. However, NO volcanism other than them has been
found. I've been studying the area for.. hmm... four years now. And the fore-
mentioned regions are quite far away. It's like you're saying that there
should be hot springs at the floor of Mississippi, the Nile or Ganges because of
plate tectonics. Not only that, but one hot spring with a length of 50 km?

You seem like you make this up as you go on.. do you? I'd wanna know, really.
I'm not accusing, I'm asking.

Jarmo

--------------------------------------------------------------------
Jarmo Korteniemi * http://www.student.oulu.fi/~jkorteni *

Planetology group, Astronomy, University of Oulu, Finland

s-posti / email: jarmo DOT#1 korteniemi AT oulu DOT#2 fi
puhelin / phone: +358 (45) 6362264
huone / room: TÄ215 (klo 12-20, ajoittain aiemminkin)
--------------------------------------------------------------------