Re: Polarized clouds on Mars, further evidence for liquid water in Solis Lacus, Mars?
From: Robert Clark (rgregoryclark_at_yahoo.com)
Date: 01/15/05
- Next message: glbrad01: "Energy, Entropy, And The Meaning Of Fundamental"
- Previous message: Gregory L. Hansen: "Re: Androcles and Draper resume Einstein 1905"
- In reply to: Robert Clark: "Re: Polarized clouds on Mars, further evidence for liquid water in Solis Lacus, Mars?"
- Messages sorted by: [ date ] [ thread ]
Date: 15 Jan 2005 06:45:06 -0800
Seasonal Trend in Water Vapor Seen from Orbit
"The seasonal trend in the amount of water vapor in Mars' atmosphere,
as observed by thermal emission spectrometer on NASA's Mars Global
Surveyor orbiter, varies by latitude. This plot starts near the
beginning of fall in the southern hemisphere for the year before the
Mars Exploration Rover mission began and ends on August 30, 2004"
When Mars reaches perihelion will be in late southern Spring. This will
be in July, 2005. It would be expected that the melting of the southern
ice cap and subsequent exposure of water ice would result in a great
increase in the amount of water in the atmosphere. However, the data
shown in the graph only goes back to the southern Fall so they may not
be including the high water content in late Spring and early Summer.
The Hubble images show the clouds over Meridiani in late Spring of
2003. This is when I'm suggesting clouds will again appear over
Meridiani in 2005, not the March 2005 mentioned in the news release.
Bob Clark
Robert Clark wrote:
> Seasonal Trend in Water Vapor Seen from Orbit
> "The seasonal trend in the amount of water vapor in Mars' atmosphere,
> as observed by thermal emission spectrometer on NASA's Mars Global
> Surveyor orbiter, varies by latitude. This plot starts near the
> beginning of fall in the southern hemisphere for the year before the
> Mars Exploration Rover mission began and ends on August 30, 2004,
> slightly more than one martian year later. Purple represents no water
> while red represents about 50 precipitable micrometers, which is
about
> 10,000 times less than on Earth. The units of time along the
horizontal
> axis are given in longitude of the Sun (Ls) as measured in a
> Mars-centered coordinate system, a way to reflect the elliptical
nature
> of Mars' orbit. On this scale, Mars is farthest from the Sun at about
> 74, which also corresponds to late fall in the southern hemisphere.
> "During the period when Mars is farthest from the Sun, the migration
of
> water vapor from the northern polar region combines with lowered
> atmospheric temperatures to produce conditions that allow formation
of
> clouds such as seen in the image "Clouds over 'Endurance' on Sol 290"
.
> Opportunity is further north than Spirit is, so there is a distinct
> difference in the amount of water vapor available to form water-ice
> clouds over the two sites. To date, Spirit has not seen any discrete,
> cirrus-like clouds such as Opportunity has photographed. Although
water
> vapor is expected to reach a maximum abundance for the Opportunity
and
> Spirit sites near spring equinox (Ls 180 or about March 2005), the
> atmospheric temperatures will very likely have warmed sufficiently to
> prevent formation of the type of clouds that Opportunity has observed
> recently. "
>
http://marsrovers.jpl.nasa.gov/gallery/press/opportunity/20041213a.html
>
> Perhaps Spirit and Opportunity won't see the thin, cirrus clouds seen
> over Meridiani, but perhaps they will see thicker clouds that could
> hold precipitation. Below I discuss the observations from Hubble
during
> late southern Spring on Mars in 2003 that showed clouds extending
into
> southern, near equatorial latitudes.
> This would be consistent with the observations from the HEND
> instrument on Mars Odyssey that found increases in near surface water
> during this period. Note though that since this is in late Spring
into
> early Summer, the ground temperatures can rise to above freezing
during
> daytime and any water frost deposits there (or precipitated ice)
would
> be expected to melt to liquid during the times of late morning to
early
> afternoon.
>
>
>
> Bob Clark
>
> =============================================
> Newsgroups:
sci.astro,alt.sci.planetary,sci.physics,sci.geo.meteorology
> From: rgregorycl...@yahoo.com (Robert Clark)
> Date: 2 Nov 2004 18:11:37 -0800
> Local: Tues, Nov 2 2004 6:11 pm
> Subject: Polarized clouds on Mars, further evidence for liquid water
in
> Solis Lacus, Mars?
>
> At the October, 2004 40th Vernadsky-Brown Conference was presented a
> report that observed polarization in the refelected light from clouds
> on Mars by the Hubble telescope:
>
> 35 - POLARIZATION CLOUDS IN THE MARTIAN ATMOSPHERE: HUBBLE SPACE
> TELESCOPE OBSERVATIONS. V. Kaydash, Yu. Shkuratov, M. Kreslavsky, G.
> Videen, M. Wolff, J. Bell.
> The 40th Vernadsky/Brown Microsymposium on Comparative Planetology.
> October 11-13, 2004, Moscow Russia
> http://www.geokhi.ru/~planetology/theses/35_kaydash_et_al.pdf
>
> Polarization of light is known to be produced by round liquid water
> drops as opposed to randomly oriented multi-faceted ice crystals. The
> process is described here:
>
> Estimate of the global distribution of stratiform supercooled liquid
> water clouds using the LITE lidar.
> Robin J. Hogan, Mukunda D. Behera,1 Ewan J. O'Connor, and Anthony J.
> Illingworth
> GEOPHYSICAL RESEARCH LETTERS, VOL. 31, L05106,
> doi:10.1029/2003GL018977, 2004
> http://www.met.rdg.ac.uk/clouds/publications/lite_mixedphase.pdf
>
> Depolarization ratio
> http://lidar.ssec.wisc.edu/papers/pp_thes/node20.htm
>
> The figures shown in the Vernadsky/Brown report show the clouds with
> the high polarization extend over the Solis Lacus region. The
> observations were taken in southern Summer on Mars in 2003. Earlier
> Viking evidence had shown this seasonal period may be when water is
> released in Solis Lacus:
>
> From: Robert Clark (rgregorycl...@yahoo.com)
> Subject: Will Mars Odyssey prove liquid water in Solis Lacus, Mars?
> Newsgroups: sci.astro
> Date: 2003-08-08 21:51:54 PST
> http://groups-beta.google.com/group/sci.astro/msg/20791dcf09a0317e
>
> Images from Mars Express have also shown autumn clouds or fogs in
> Solis that may contact the ground and form liquid water:
>
> From: Robert Clark (rgregorycl...@yahoo.com)
> Subject: Further on liquid water in Solis Lacus, Mars.
> Newsgroups: sci.astro, alt.sci.planetary, sci.physics,
> sci.geo.meteorology
> Date: 2004-10-09 13:39:43 PST
> http://groups-beta.google.com/group/sci.astro/msg/094907a1d49c5b84
>
>
> Bob Clark
>
> ================================================
> Newsgroups: sci.astro, alt.sci.planetary, sci.physics,
sci.geo.geology,
> sci.geo.meteorology
> From: "Robert Clark" <rgregorycl...@yahoo.com>
> Date: 25 Dec 2004 12:58:34 -0800
> Local: Sat, Dec 25 2004 12:58 pm
> Subject: More on "Frost on the rover solar panels".
>
> Imaging at the Opportunity rover landing site in Meridiani Planum
> confirms observations using the HEND instrument on Mars Observer that
> water/ice is deposited near the equator seasonally on Mars:
>
> Space Sciences
> Whoa! Frost on the solar panels?
> Posted by Robert Clark on 12/14/2004 7:32:38 AM
> In Reply to: Sabkha or playa, take your pick... posted by Nick
Hoffman
> on 12/13/2004 6:23:08 PM
> http://habitablezone.com/space/messages/360805.html
>
> However, the HEND instrument shows the greatest amount is deposited
> during southern Summer:
>
> 47 - EVIDENCE OF THE SEASONAL REDISTRIBUTION OF WATER IN THE
SURFICIAL
> MARTIAN REGOLITH BASED ON ANALYSIS OF THE HEND MAPPING DATA.
> R.O. Kuzmin, E.V. Zabalueva, I.G. Mitrofanov, M.L. Litvak, A.V.
> Parshukov, V.Yu. Grin'kov, W. Boynton, R.S. Saunders.
> "As it well seen from fig.1b,c,d, two distinctive "hollows" of
> neutrons flux reduction have been appeared in the northern hemisphere
> during northern summer at Ls=130°-170° and in first half of
northern
> winter at Ls=270°-330°, being extended from high to low latitudes.
At
> that, later "hollow" (Ls=270°-330°) is characterized by much
> stronger reduction of the neutrons flux and it traces from northern
> polar region up to low latitudes in the southern hemisphere. The
first
> "hollow" is related with periods of the northern middle summer,
> while the second one - with of the southern middle summer. In both
> case the residual polar caps serve as main source of the water in the
> Martian atmosphere."
> p. 2
> http://www.geokhi.ru/~planetology/theses/47_kuzmin_et_al.pdf
>
> Opportunity landed just barely after this time in southern Summer at
> about LS 340° (LS stands for solar longitude and indicates Mars
> position in its orbit.)
> However, it is notable that Spirit did land near the end of the time
> period of Ls=270°-330°. Spirit is closer to the southern pole and
> this may explain how could experience deposition during this period
> while apparently not during the current northern Summer. Then the
> controversial indications of mud at the Spirit landing site early in
> the mission may indeed have been indications of this summer-time
water
> deposition.
> Opportunity has observed clouds during the current water deposition
> period and since the amount of atmospherically deposited water is
> greater during southern Summer, we would expect the cloud density to
be
> even greater then. Indeed it could be of sufficient density to allow
> precipitation which could reach the ground as rain.
> The next Ls=270°-330° period begins in August, 2005.
>
> Come on Opportunity!
> Bob Clark
>
> =====================================================
- Next message: glbrad01: "Energy, Entropy, And The Meaning Of Fundamental"
- Previous message: Gregory L. Hansen: "Re: Androcles and Draper resume Einstein 1905"
- In reply to: Robert Clark: "Re: Polarized clouds on Mars, further evidence for liquid water in Solis Lacus, Mars?"
- Messages sorted by: [ date ] [ thread ]
Relevant Pages
|
