Red Dawn. Red Sky

"Jeff Lerner" wrote in message ...
After thousands of years of looking at blue skies, are there any anticipated
psychological challenges awaiting Martian astronauts waking up to a red dawn
and looking at red skies all Martian day ?? From pictures taken by the
various Martian landers we get an idea as to what a Martian day looks like.
Kind of strikes me as an overcast look to it. I know how I feel after a few
days of no sunshine, cloudy skies. Will Martian astronauts have to deal with
the "blue-less sky" blues ??

Jeff Lerner

"Red Dawn"? "Red Sky"? Are we talkibg about the U.S.S.R.? Or the
P.R.C.?


Anyway. As it already been mentioned, mmany pictures from Mars are
actually just modified pictures to make the Martian sky look red, the
Martian sky probably is more blue-ish than some of the pictures imply.
The Martian sky probably would just look like on how the Earth's sky
look like when viewed from a high altitude.

In article ,
EAC wrote:
The Martian sky probably would just look like on how the Earth's sky
look like when viewed from a high altitude.

Uh, no, there really is a lot of dust in the Martian air. (It shows up
in other ways too, e.g. the sky stays bright well after sunset.)

"Before the Viking landings, scientists and artists had pictured a dark
blue Martian sky, like that at very high altitude over Earth. The first
Viking photos showed a much brighter sky than expected; controllers
applied color controls that gave a blue sky tint to the first photos
handed out to the press! Only after a day of calibration did the Viking
scientists discover that reddish light dominates in the delicate balance
of sky colors; properly processed photos show a pink Martian sky."
(Hartmann, "Moons and Planets", 3rd ed., p. 410.)

Moreover, history repeated itself: based on atmospheric models and Hubble
images, there were pre-landing predictions that Mars Pathfinder would see
a blue sky. Nope, pinkish-tan like the Viking sky.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

And yes, the sky does take on a very odd shade
that's hard to describe.

Indigo?

Richard wrote:

And yes, the sky does take on a very odd shade
that's hard to describe.



Indigo?


That's probably as good a choice of shade as any, to me sort of a
translucent dark indigo/grayish shade.
It just occurred to me that the effect was like looking far higher into
the atmosphere than one normally could during daylight.
It's been so long that I'm having a hard time remembering what exactly
it looked like.
Could the color (at least near and during totality) have something to do
with the fact that the illumination is coming from the Sun's corona,
which is far more toward the UV end of the spectrum than normal sunlight.

Pat

"Richard" wrote in news:co3779$2079$1
@arachne.labyrinth.net.au:

And yes, the sky does take on a very odd shade
that's hard to describe.

Indigo?

Yes, that's about it. Not the sort of sky color you'd be
looking for at around high noon.

Also interesting to see the images of the crescent sun
projected onto the ground through tree leaves acting
like pinhole lenses.

--Damon

"Greg D. Moore \(Strider\)" wrote in
:


There's a distinct difference in the way things look from a normal
incandescent flashlight bulb and an LED one. Takes a little getting
used to.

Sodium vapor lamps, which are nearly monochromatic, can certainly
skew color perception; my light turquose truck looks cobalt
blue and I sometimes have to stop and look closely at details
to be sure it's my truck.

--Damon, who drives his late Dad's Dakota

In article ,
Pat Flannery writes:


Neil Gerace wrote:

Yes, I noticed that weird lighting during the eclipse of 4 Dec 2002.

Did you notice an odd stillness, like sound was being deadened and the
wind dying? I noticed that during the total eclipse that went through
North Dakota in 1979. (I'd been waiting around for that one ever since I
was a kid- I only had to drive around 150 miles to see it. Won't have
another one in the state till 2044.)

Yes, as a matter of fact, I have. Well, I should clarify that - I
have subjectively perceived it, and not actually measured it. I
expect it come from a couple of factors, both pretty much
psychologcal. My impression was that the background noise pretty much
went away. A lot of that is generated by animals - Birds, Mice,
Voles, Shoggoths, etc. When the Unexpected Dark shows up, they hole
up and wait to see what's going to happen. I've seen similar behavior
during thunderstorms (Birds beginning to sing is a good indication
that the rain's going to stop soon), and when
unknown/hazardous/melevolent things show up.. I was out walking the
dog one morning when I noticed that it was Real Quiet - all the
birds/mice/voles/shoggoths were as still as, well, mice. Then the
Crow flew past - at about knee height, making for the treeline at Best
Speed. The reason for this soon became apparant - the local Vulture
Flock had, for some reason, taken umbrage at the Crow (Or the Crow had
taken the Vulture's umbrage - they're a kleptomaniacal lot) and were
stacking up to begin running passes on it. There were about a dozen
of them, with wingspans in the 6-8 ft range, stacked up from about 10'
altitude to 100', all apparently under the command of the Vulture on
Top (An AWACS Vulture? I dunno.) The Low Vultures effectively boxed
in the Crow, keeping him from turning, while the High Vultures made
repeated Energy Maneuverability-type overhead passes on the Crow.
After the Crow reached the Pine woods, (Interior Pines, so no branches
except at the top), and he could fly through with overhead cover, The
Vulture reassebled their formation and went to patrol the
superhighway, in their quest for Pontiac Vulture Chow. When the
Vultures left, the critters started moving around again.

A second factor may be that since somtething different is happening,
our expectatiuons about what we are perceiving are jarred, and we're
interpreting outr sensory input a bit skewed.

--
Pete Stickney

Without data, all you have are opinions

Peter Stickney wrote:

Did you notice an odd stillness, like sound was being deadened and the
wind dying? I noticed that during the total eclipse that went through
North Dakota in 1979. (I'd been waiting around for that one ever since I
was a kid- I only had to drive around 150 miles to see it. Won't have
another one in the state till 2044.)


Yes, as a matter of fact, I have. Well, I should clarify that - I
have subjectively perceived it, and not actually measured it. I
expect it come from a couple of factors, both pretty much
psychologcal. My impression was that the background noise pretty much
went away. A lot of that is generated by animals - Birds, Mice,
Voles, Shoggoths, etc.

One also gets noise from wind interacting with vegetation. During
an eclipse, solar energy input is reduced or largely eliminated,
reducing surface heating and hence convection.

Wind shear can also focus sound back to the ground (sound coming
from upwind tends to be bent back downwards), which could amplify
noise.

Paul

"Damon Hill" wrote in message
34...

Sodium vapor lamps, which are nearly monochromatic, can certainly
skew color perception; my light turquose truck looks cobalt
blue and I sometimes have to stop and look closely at details
to be sure it's my truck.

get an unusual bumper sticker, or put an American flag somewhere unusual
(mid-tailgate?). That's the only way I can reliably find my white Accord in
teh parking lot g

--
Terrell Miller


"The truth will set you free. So will pork and beans."
-She Devil's Father

"Terrell Miller" wrote:

"Damon Hill" wrote in message
. 134...

Sodium vapor lamps, which are nearly monochromatic, can certainly
skew color perception; my light turquose truck looks cobalt
blue and I sometimes have to stop and look closely at details
to be sure it's my truck.

get an unusual bumper sticker, or put an American flag somewhere unusual
(mid-tailgate?). That's the only way I can reliably find my white Accord in
teh parking lot g

nod Being the owner of a grey mini-van of a popular model... I'm
often glad I have a bumper sticker that only a hundred or so people
have.

D.
--
Touch-twice life. Eat. Drink. Laugh.

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL