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Upcoming
July Meeting on the 11th!!
This month's meeting be on the SRSU campus in the Warnock Science Bldg..
Room 201 on Wednesday, 11 July at 7:30 p.m. Walt Frerck will be presenting
a program on the Mars Rovers.
Again, at this writing, only a few members have paid there 2007 dues. Since
our membership has dwindled it is very important to the club's survival
that each member pay their dues in a timely fashion. So, if you've yet
to pay your dues and are unable to attend this months meeting, please mail
a check made payable to the BBAS for $20 to the Treasurer at the following
address:
Chuck Dobbins
BBAS Secretary/Treasurer
616 N Cherry St
Alpine, TX 79830
No meeting minutes or treasurer's
report are contained in this issue.
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NASA Mars
Rover Ready for
Descent Into
Crater
from NASA via Universe
Today
http://www.universetoday.com/2007/06/28/
opportunity-is-ready-descend-into-victoria-crater/
From the NASA Press
Release at http://www.nasa.gov/mission_pages/mer/mer-20070628.html
WASHINGTON 28 June 2007: NASA's Mars rover Opportunity is
scheduled to begin a descent down a rock-paved slope into the Red Planet's
massive Victoria Crater. This latest trek carries real risk for the long-lived
robotic explorer, but NASA and the Mars Rover science team expect it to
provide valuable science.
Opportunity already has been exploring layered rocks in cliffs around Victoria
Crater. The team has planned the descent carefully to enable an eventual
exit, but Opportunity could become trapped inside the crater or lose some
capabilities. The rover has operated more than 12 times longer than its
originally intended 90 days.
The scientific allure is the chance to examine and investigate the compositions
and textures of exposed materials in the crater's depths for clues about
ancient, wet environments. As the rover travels farther down the slope,
it will be able to examine increasingly older rocks in the exposed walls
of the crater.
The route followed
by NASA's Mars Exploration Rover Opportunity during its
exploration partway
around the rim of Victoria Crater is marked on this map.
Image credit: NASA/JPL/Cornell/University
of Arizona/Ohio State University.
"While we take seriously the uncertainty about whether Opportunity will
climb back out, the potential value of investigations that appear possible
inside the crater convinced me to authorize the team to move forward into
Victoria Crater," said Alan Stern, NASA associate administrator, Science
Mission Directorate, NASA Headquarters, Washington. "It is a calculated
risk worth taking, particularly because this mission has far exceeded its
original goals."
The robotic geologist will enter Victoria Crater through an alcove named
Duck Bay. The eroding crater has a scalloped rim of cliff-like promontories,
or capes, alternating with more gently sloped alcoves, or bays.
A meteor impact millions of years ago excavated Victoria, which lies approximately
4 miles south of where Opportunity landed in January 2004. The impact-created
bowl is half a mile across and about five times as wide as Endurance Crater,
where Opportunity spent more than six months exploring in 2004.
The rover began the journey to Victoria from Endurance 30 months ago. It
reached the rim at Duck Bay nine months ago. Opportunity then drove approximately
a quarter of the way clockwise around the rim, examining rock layers visible
in the promontories and possible entry routes in the alcoves. Now, the
rover has returned to the most favorable entry point.
"Duck Bay looks like the best candidate for entry," said John Callas, rover
project manager, NASA's Jet Propulsion Laboratory, Pasadena, Calif. "It
has slopes of 15 to 20 degrees and exposed bedrock for safe driving."
If all of its six wheels continue working, engineers expect Opportunity
to be able to climb back out of the crater. However, Opportunity's twin
rover Spirit lost the use of one wheel more than a year ago, diminishing
its climbing ability.
"These rovers are well past their design lifetimes, and another wheel could
fail on either rover at any time," Callas said. "If Opportunity were to
lose the use of a wheel inside Victoria Crater, it would make it very difficult,
perhaps impossible, to climb back out."
"We don't want this to be a one-way trip," said Steve Squyres, principal
investigator for the rovers' science instruments, Cornell University, Ithaca,
N.Y. "We still have some excellent science targets out on the plains that
we would like to visit after Victoria. But if Opportunity becomes trapped
there, it will be worth the knowledge gained."
The Jet Propulsion Laboratory manages the Mars Exploration Rover project
for NASA's Science Mission Directorate.
This image captured
by NASA's Mars Exploration Rover Opportunity shows "Cape St.
Vincent," one of the
many promontories that jut out from the walls of Victoria Crater, Mars.
The material at the
top of the promontory consists of loose, jumbled rock, then a bit further
down into the crater,
abruptly transitions to solid bedrock. This transition point is marked
by
a bright band of rock,
visible around the entire crater.
Scientists say
this bright band represents what used to be the surface of Mars before
it was
impacted to form Victoria
Crater. As Opportunity begins to descend into the crater in early
July 2007, it will
examine the band carefully at an accessible location with a gentle slope.
These investigations
might help determine if the band's brighter appearance is the result of
ancient interactions
with the Martian atmosphere.
This image was taken by Opportunity's panoramic camera on sol 1167 (May
6, 2007).
It is presented in
approximately true color.
Image credit: NASA/JPL/
Cornell.
Additional images
plus animations are at the NASA
web site.
For more information on the Mars
Rovers, visit:
http://www.nasa.gov/rovers
Visuals describing this decision
and the anticipated science can be viewed at:
http://www.nasa.gov/mission_pages/mer/070628
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