Online Articles and News About
- 2010 October 29. Liquid Water Found on Mars, But It's Still a Hard Road for Life. By Richard A. Kerr, Science. [Must be an AAAS member to read the full article] Excerpt: Researchers appear to have finally achieved one of the Phoenix lander's primary goals. After digging through piles of data left from the mission to Mars more than 2 years ago, they've discovered signs that liquid water has lately flowed on the frigid planet.
…Phoenix team members report that liquid water—probably only thin films of it—appears to have concentrated salts onto small patches of soil that Phoenix uncovered. The water may be liquid every martian spring or summer, or perhaps it only melted many millennia ago….
- 2010 September 9. NASA RELEASE 10-216: NASA Data Shed New Light About Water and Volcanoes on Mars. Excerpt: Data from NASA's Phoenix Mars Lander suggest liquid water has interacted with the Martian surface throughout the planet's history and into modern times. The research also provides new evidence that volcanic activity has persisted on the Red Planet into geologically recent times, several million years ago.
Although the lander, which arrived on Mars on May 25, 2008, is no longer operating, NASA scientists continue to analyze data gathered from that mission. These recent findings are based on data about the planet's carbon dioxide, which makes up about 95 percent of the Martian atmosphere.
...Phoenix precisely measured isotopes of carbon and oxygen in the carbon dioxide of the Martian atmosphere. Isotopes are variants of the same element with different atomic weights... The paper explains the ratios of stable isotopes and their implications for the history of Martian water and volcanoes.
- 2010 July 23. NASA RELEASE: 10-176. NASA Spacecraft Camera Yields Most Accurate Mars Map Ever. Excerpt: WASHINGTON -- A camera aboard NASA's Mars Odyssey spacecraft has helped develop the most accurate global Martian map ever. Researchers and the public can access the map via several websites and explore and survey the entire surface of the Red Planet... The map was constructed using nearly 21,000 images from the Thermal Emission Imaging System, or THEMIS, a multi-band infrared camera on Odyssey... The pictures have been smoothed, matched, blended and cartographically controlled to make a giant mosaic. Users can pan around images and zoom into them. At full zoom, the smallest surface details are 330 feet wide. While portions of Mars have been mapped at higher resolution, this map provides the most accurate view so far of the entire planet.
...Working with THEMIS images from the new map, the public can contribute to Mars exploration by aligning the images to within a pixel's accuracy at NASA's "Be A Martian" website, which was developed in cooperation with Microsoft Corp. Users can visit the site at:
..."The Mars Odyssey THEMIS team has assembled a spectacular product that will be the base map for Mars researchers for many years to come," said Jeffrey Plaut, Odyssey project scientist at JPL. "The map lays the framework for global studies of properties such as the mineral composition and physical nature of the surface materials."
...Other sites build upon the base map. At Mars Image Explorer, which includes images from every Mars orbital mission since the mid-1970s, users can search for images using a map of Mars
..."The broad purpose underlying all these sites is to make Mars exploration easy and engaging for everyone," [Phillip] Christensen said. "We are trying to create a user-friendly interface between the public and NASA's Planetary Data System, which does a terrific job of collecting, validating and archiving data."
- 2010 June 3. NASA RELEASE: 10-131. NASA Rover Finds Clue to Mars' Past and Environment for Life. Excerpt: PASADENA, Calif. -- Rocks examined by NASA's Spirit Mars Rover hold evidence of a wet, non-acidic ancient environment that may have been favorable for life. Confirming this mineral clue took four years of analysis by several scientists. …An outcrop that Spirit examined in late 2005 revealed high concentrations of carbonate, which originates in wet, near-neutral conditions, but dissolves in acid. The ancient water indicated by this find was not acidic.
…"This is one of the most significant findings by the rovers," said Steve Squyres of Cornell University in Ithaca, N.Y. Squyres is principal investigator for the Mars twin rovers, Spirit and Opportunity, and a co-author of the new report. "A substantial carbonate deposit in a Mars outcrop tells us that conditions that could have been quite favorable for life were present at one time in that place.
…Massive carbonate deposits on Mars have been sought for years without much success. Numerous channels apparently carved by flows of liquid water on ancient Mars suggest the planet was formerly warmer, thanks to greenhouse warming from a thicker atmosphere than exists now. The ancient, dense Martian atmosphere was probably rich in carbon dioxide, because that gas makes up nearly all the modern, very thin atmosphere.
- 2010 May 26. NASA RELEASE: 10-122. NASA Spacecraft Penetrates Mysteries of Martian Ice Cap. Excerpt: PASADENA, Calif. -- Data from NASA's Mars Reconnaissance Orbiter (MRO) have helped scientists solve a pair of mysteries dating back four decades and provided new information about climate change on the Red Planet.
…"SHARAD is giving us a beautifully detailed view of ice deposits, whether at the poles or buried in mid-latitudes, as they changed on Mars over the last few million years," said Rich Zurek, MRO project scientist at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
...One of the most distinctive features of the northern ice cap is Chasma Boreale, a canyon about as long as Earth's Grand Canyon but deeper and wider. Some scientists believe Chasma Boreale was created when volcanic heat melted the bottom of the ice sheet and triggered a catastrophic flood. Others suggest strong polar winds carved the canyon out of a dome of ice.
…Data from Mars now points to both the canyon and spiral troughs being created and shaped primarily by wind. Rather than being cut into existing ice very recently, the features formed over millions of years as the ice sheet grew. By influencing wind patterns, the shape of underlying, older ice controlled where and how the features grew.
- 2010 January 27. NASA
gives up effort to free Mars rover. By David Pearlman, SF Chronicle. Excerpt:
Scientists controlling the six-year journey of Spirit,
the robot explorer stuck fast in a patch of sand on Mars,
have given up efforts to free it.
It will now serve as a research outpost standing alone
on the red planet, and if it survives the deep freeze
of the coming Martian winter, the once-mobile vehicle
will try to help scientists solve a long-standing mystery
about the planet's core: whether it's liquid like Earth's
or solid all the way through.
Spirit landed on Mars in January 2004 and traveled across
nearly 5 miles of the planet's sandy surface and rocks.
Along the way, it reported on evidence of past water
that the chemistry of the rocks revealed. Ten months
ago, one of its six wheels broke through a patch of crusty
soil and the vehicle sank belly-deep into soft sand.
Engineers have tried varied strategies to free the vehicle;
they've commanded Spirit to spin its working wheels forward
and backward - one of its wheels had failed in 2006,
and another quit working in November. Every effort the
scientists made to free Spirit failed.
...If Spirit makes it through winter, its mission will
include studying the detailed chemistry of the sand within reach
of the instruments on its robotic arm, monitoring the
Martian atmosphere, and watching how the Martian wind
moves soil particles as the wind direction changes.
...By watching over many months for tiny variations in
the wobble of the planet as it spins on its axis, Squyres
said, scientists will be able to determine whether or
not Mars has a liquid core, or whether the planet is
- 2009 September 24. NASA
RELEASE: 09-224. NASA SPACECRAFT SEES ICE ON MARS EXPOSED
BY METEOR IMPACTS. Excerpt:
PASADENA, Calif. -- NASA's Mars Reconnaissance Orbiter
has revealed frozen water hiding just below the surface
of mid-latitude Mars. The spacecraft's observations were
obtained from orbit after meteorites excavated fresh
craters on the Red Planet.
Scientists controlling instruments on the orbiter found
bright ice exposed at five Martian sites with new craters
that range in depth from approximately half a meter to
2.5 meters (1.5 feet to 8 feet). The craters did not
exist in earlier images of the same sites. Some of the
craters show a thin layer of bright ice atop darker underlying
material. The bright patches darkened in the weeks following
initial observations, as the freshly exposed ice vaporized
into the thin Martian atmosphere. One of the new craters
had a bright patch of material large enough for one of
the orbiter's instruments to confirm it is water-ice.
The finds indicate water-ice occurs beneath Mars' surface
halfway between the north pole and the equator, a lower
latitude than expected in the Martian climate.
"This ice is a relic of a more humid climate from
perhaps just several thousand years ago," said Shane
Byrne of the University of Arizona, Tucson....
- 2009 May 21. RELEASE
: 09-117. NASA Rover Sees Variable Environmental
History at Martian Crater. Excerpt:
PASADENA, Calif. -- One of NASA's two Mars rovers
has recorded a compelling saga of environmental changes
that occurred over billions of years at a Martian
The Mars rover, Opportunity, surveyed the rim and interior
of Victoria Crater on the Red Planet from September 2006
through August 2008....
The rover revealed the effects of wind and water. The
data show water repeatedly came and left billions of
years ago. Wind persisted much longer, heaping sand into
dunes between ancient water episodes. These activities
still shape the landscape today. At Victoria, steep cliffs
and gentler alcoves alternate around the edge of a bowl
about a half a mile in diameter. The scalloped edge and
other features indicate the crater once was smaller than
it is today, but wind erosion has widened it gradually.
"What drew us to Victoria Crater is the thick cross-section
of rock layers exposed there," said Steve Squyres
of Cornell University in Ithaca, N.Y. Squyres is the
principal investigator for the science payloads on Opportunity
and its twin rover Spirit. "The impact that excavated
the crater millions of years ago provided a golden opportunity,
and the durability of the rover enabled us to take advantage
- 2008 November 20. RELEASE
: 08-304. NASA Spacecraft Detects Buried Glaciers
on Mars. Excerpt:
PASADENA, Calif.-- NASA's Mars Reconnaissance Orbiter
has revealed vast Martian glaciers of water ice under
protective blankets of rocky debris at much lower latitudes
than any ice previously identified on the Red Planet.
..."Altogether, these glaciers almost certainly
represent the largest reservoir of water ice on Mars
that is not in the polar caps," said John W. Holt
of the University of Texas at Austin, who is lead author
of the report. "Just one of the features we examined
is three times larger than the city of Los Angeles and
up to half a mile thick. And there are many more. In
addition to their scientific value, they could be a source
of water to support future exploration of Mars."
Scientists have been puzzled by what are known as aprons
-- gently sloping areas containing rocky deposits at
the bases of taller geographical features -- since NASA's
Viking orbiters first observed them on the Martian surface
in the1970s. One theory has been that the aprons are
flows of rocky debris lubricated by a small amount ice.
Now, the shallow radar instrument on the Mars Reconnaissance
Orbiter has provided scientists an answer to this Martian
"These results are the smoking gun pointing to the
presence of large amounts of water ice at these latitudes," said
Ali Safaeinili, a shallow radar instruments team member
with NASA's Jet Propulsion Laboratory in Pasadena, Calif....
- 2008 October 28. RELEASE
: 08-273. NASA Orbiter Reveals Details of a Wetter
Mars. Excerpt: WASHINGTON --
NASA's Mars Reconnaissance Orbiter has observed a
new category of minerals spread across large regions
of Mars. This discovery suggests that liquid water
remained on the planet's surface a billion years
later than scientists believed, and it played an
important role in shaping the planet's surface and
possibly hosting life.
Researchers examining data from the orbiter's Compact
Reconnaissance Imaging Spectrometer for Mars have found
evidence of hydrated silica, commonly known as opal.
The hydrated, or water-containing, mineral deposits
are telltale signs of where and when water was present
on ancient Mars.
"This is an exciting discovery because it extends
the time range for liquid water on Mars, and the
places where it might have supported life," said Scott
Murchie, the spectrometer's principal investigator
at the Johns Hopkins University Applied Physics Laboratory
in Laurel, Md. "The identification of opaline
silica tells us that water may have existed as recently
as 2 billion years ago."
..."We see numerous outcrops of opal-like minerals,
commonly in thin layers extending for very long distances
around the rim of Valles Marineris and sometimes
within the canyon system itself," said Ralph Milliken
of NASA's Jet Propulsion Laboratory in Pasadena, Calif.
...The study reveals that the minerals,
which also were recently found in Gusev Crater by NASA's
Mars rover Spirit, are widespread and occur in relatively
..."What's important is that the longer liquid
water existed on Mars, the longer the window during
which Mars may have supported life," says Milliken. "The
opaline silica deposits would be good places to explore
to assess the potential for habitability on Mars,
especially in these younger terrains." ...
- 2008 Sep 8. An
Icy Discovery on Mars, but Where's the Water? By
KENNETH CHANG, NY Times. Excerpt:
After a much ballyhooed discovery two months ago
of water ice in the northern plains of Mars, scientists
are now perplexed by the water that NASA's Phoenix
Mars lander has not found.
...Phoenix's weather station has also detected wisps
of water vapor in the thin Martian air, and scientists
expected that as the nighttime temperature plunged
to minus-110 degrees Fahrenheit from minus-20 - and
with it the amount of moisture that the Martian air
can hold - minuscule specks of moisture would glom
onto dust particles at the surface. The presence of
water would show up in electrical measurements by a
probe stuck into the soil. Except Mars has not cooperated.
"We're seeing nothing," said Aaron Zent of
the NASA Ames Research Center at Moffett Field, Calif.,
the lead scientist for Phoenix's thermal and electroconductivity
probe. "Big fat nothing."
Actually, the first measurement did yield the expected
readings. "A lovely signal," Dr. Zent said. "But
we never saw it again."
Every subsequent measurement, taken at almost all hours
of the day, indicated dry soil.
...The moisture in the air during the day has to go
somewhere at night, and that somewhere seems almost
certain to be the soil. "It has to," Dr.
Zent said. "There's no other place for it to go.
The soil is sucking it up at night. We certainly expect
that we should be able to see some of this."
...The next step is for Phoenix to jam its electroconductivity
probe deeper into the soil, closer to the ice layer.
Maybe then, Phoenix will once again discover water.
- 2008 Aug 14. PHOENIX
MICROSCOPE TAKES FIRST IMAGE OF MARTIAN DUST PARTICLE. NASA's
Phoenix Mars Lander has taken the first-ever image
of a single particle of Mars' ubiquitous dust, using
its atomic force microscope. The particle -- shown
at higher magnification than anything ever seen from
another world -- is a rounded particle about one
micrometer, or one millionth of a meter, across.
It is a speck of the dust that cloaks Mars. Such
dust particles color the Martian sky pink, feed storms
that regularly envelop the planet and produce Mars'
distinctive red soil.
- 2008 July 31. RELEASE:
08-195. NASA SPACECRAFT CONFIRMS MARTIAN WATER, MISSION
EXTENDED. Excerpt: TUCSON, Ariz.
-- Laboratory tests aboard NASA's Phoenix Mars Lander
have identified water in a soil sample. The lander's
robotic arm delivered the sample Wednesday to an instrument
that identifies vapors produced by the heating of samples.
"We have water," said William Boynton of
the University of Arizona, lead scientist for the Thermal
and Evolved-Gas Analyzer, or TEGA. "We've seen
evidence for this water ice before in observations
by the Mars Odyssey orbiter and in disappearing chunks
observed by Phoenix last month, but this is the first
time Martian water has been touched and tasted."
With enticing results so far and the spacecraft in
good shape, NASA also announced operational funding
for the mission will extend through Sept. 30. The original
prime mission of three months ends in late August.
The mission extension adds five weeks to the 90 days
of the prime mission.
...The soil sample came from a trench approximately
2 inches deep. When the robotic arm first reached that
depth, it hit a hard layer of frozen soil. Two attempts
to deliver samples of icy soil on days when fresh material
was exposed were foiled when the samples became stuck
inside the scoop. Most of the material in Wednesday's
sample had been exposed to the air for two days, letting
some of the water in the sample vaporize away and making
the soil easier to handle.
"Mars is giving us some surprises," said
Phoenix principal investigator Peter Smith of the University
of Arizona. "We're excited because surprises are
where discoveries come from. One surprise is how the
soil is behaving. The ice-rich layers stick to the
scoop when poised in the sun above the deck, different
from what we expected from all the Mars simulation
testing we've done. ...For more about Phoenix, visit:
- 2008 July 16. NASA
SPACECRAFT SHOWS DIVERSE, WET ENVIRONMENTS ON ANCIENT
MARS. RELEASE : 08-177. Excerpt:
Two studies based on data from NASA's Mars Reconnaissance
Orbiter have revealed that the Red Planet once hosted
vast lakes, flowing rivers and a variety of other wet
environments that had the potential to support life.
For more specific information on the two studies, visit:
- 2008 May 15. NASA
SATELLITE FINDS INTERIOR OF MARS IS COLDER. NASA
RELEASE: 08-128. Excerpt:
WASHINGTON -- New observations from NASA's Mars Reconnaissance
Orbiter indicate that the crust and upper mantle of
Mars are stiffer and colder than previously thought.
The findings suggest any liquid water that might exist
below the planet's surface and any possible organisms
living in that water, would be located deeper than
scientists had suspected. "We found that the rocky
surface of Mars is not bending under the load of the
north polar ice cap," said Roger Phillips of the
Southwest Research Institute in Boulder, Colo.
..."The lithosphere of a planet is the rigid part.
On Earth, the lithosphere is the part that breaks during
an earthquake," said Suzanne Smrekar, deputy project
scientist for Mars Reconnaissance Orbiter at JPL. "The
ability of the radar to see through the ice cap and
determine that there is no bending of the lithosphere
gives us a good idea of present day temperatures inside
Mars for the first time."
...The radar pictures also reveal four zones of finely
spaced layers of ice and dust separated by thick layers
of nearly pure ice. Scientists think this pattern of
thick ice-free layers represents cycles of climate
change on Mars on a time scale of roughly one million
years. Such climate changes are caused by variations
in the tilt of the planet's rotational axis and in
the eccentricity of its orbit around the sun. The observations
support the idea that the north polar ice cap is geologically
active and relatively young, at about 4 million years.
- 2008 Apr 25. Icy
Active Mars. ...The prevailing
thinking is that Mars is a planet whose active climate
has been confined to the distant past. About 3.5
billion years ago, the Red Planet had extensive flowing
water and then fell quiet - deadly quiet. It didn't
seem the climate had changed much since. Now, in
a research article that graces the May cover of Geology,
scientists at Brown University think Mars' climate
has been much more dynamic than previously believed.
The findings could have important implications in
determining whether or not Mars was ever a suitable
habitat for life in the planet's past. After examining
stunning high-resolution images taken last year by
the Mars Reconnaissance Orbiter, the researchers
have documented for the first time that ice packs
at least 1 kilometer (0.6 miles) thick and perhaps
2.5 kilometers (1.6 miles) thick existed along Mars'
mid-latitude belt as recently as 100 million years
ago. In addition, the team believes other images
tell them that glaciers flowed in localized areas
in the last 10 to 100 million years - akin to the
day before yesterday in Mars' geological timeline.
- 2008 Mar 20. Mars
is 'covered in table salt'. By Helen Briggs, Science
reporter, BBC News. Excerpt:
Mars appears to be covered in salt crystals from ancient
dried-up lakes, new evidence suggests. A Nasa probe
has found signs that the southern hemisphere is dusted
with chloride mineral, perhaps "table salt".
US scientists think the mineral formed when water evaporated
from salty lakes or soil billions of years ago. The
deposits, similar to salt-pans on Earth, are a good
place to search for traces of past life preserved in
salt, they report in the journal Science. The evidence
comes from a camera on Mars Odyssey, which has been
mapping the Red Planet since early 2002.
...Team member Professor Philip Christensen, of the
School of Earth and Planetary Exploration at Arizona
State University, Tempe, said ... "Two possible
mechanisms would be the evaporation of a large body
of water (like a salt lake on Earth), or capillary
action in the soil that could draw salt-rich water
toward the surface, where the water evaporates and
the salt is left behind and accumulates. Either case
is exciting because it implies a large amount of water
near the surface."....
See also, NASA
- 2008 Mar 3. Avalanches
on Mars. ...A NASA spacecraft
in orbit around Mars has taken the first ever image
of active avalanches near the Red Planet's north pole.
..."We were checking for springtime changes in
the carbon-dioxide frost covering a northern dune field,
and finding the avalanches was completely serendipitous," says
JPL's Candice Hansen, deputy principal investigator
for HiRISE. ..."We don't know what set off these
landslides," says Patrick Russell of the University
of Berne, Switzerland, a HiRISE team collaborator. "We
plan to take more images of the site through the changing
Martian seasons to see if this kind of avalanche happens
all year or is restricted to early spring." ..."If
blocks of ice broke loose and fell, we expect the water
in them will be changing from solid to gas," Russell
says. "We'll be watching to see if blocks and
other debris shrink in size. What we learn could give
us a better understanding of one part of the water
cycle on Mars."
The avalanche photo is one of approximately 2,400 HiRISE
images released on March 3, 2008.
- 2008 Feb 21. Research
Explains Formation of Unique Martian Fans. By
KENNETH CHANG , NY Times. To
figure out an odd landscape feature on Mars, play in
a big sandbox. Enlist some high school students, too.
That's what some scientists at the Utrecht University
in the Netherlands did, and they believe they now know
how sediment deposits spilling out of the mouth of some
water channels on Mars were shaped in a series of terraces
that look like terraced rice paddies.
But no similar natural formations have been seen in river
deltas on Earth. Usually river sediments spill out in
a smooth, sloping fan like the Mississippi delta.
Planetary geologists have been speculating about the
terraced fans since they were first spotted by NASA's
Mars Global Surveyor eight years ago. About 10 stepped
fans have been identified, most at the base of a steep
slope emptying into a basin like an impact crater. (Most
of the 200 sediment fans seen on Mars do not have the
stepped structure. Another mystery is why many of the
river channels seem to have no sediment deposit at all.)
Some scientists suggested the terraced fans were the
result of repeated shore erosion as a lake in the basin
dried up. Others thought repeated landslides might have
formed the steps.
The sandbox experiment, reported in Thursday's issue
of the journal Nature, supports a third notion. The terraces
form by the interaction of the sediment flow with the
water's edge, which is rising as the basin fills. "Where
that's happening, you're getting a little lip," said
Erin R. Kraal, the lead author of the Nature paper. Pulses
of flow and sediment produced multiple terraces.
"They're just stacking one atop the other," she
said. While a postdoctoral researcher at Utrecht, Dr.
Kraal became intrigued by the terraced fans.... Utrecht
has a set-up known as Eurotank, essentially a 16- by
40-foot sandbox for studying sedimentary dynamics.
High school students visiting the laboratory as part
of an educational project saw the Mars pictures on the
laboratory walls and were interested in helping on an
experiment, which eventually turned into a short educational
movie about the Martian fans.
The students dug a crater in the sandbox and shaped a
water channel. Then they sent water down the channel
- and the result was a terraced fan, just as on Mars.
"We didn't expect it to be so successful the first
time," said Dr. Kraal, now a research scientist
at Virginia Polytechnic Institute and State University. "We
were really surprised they formed so quickly and so easily."....
- 21 September 2007 NASA RELEASE: 07-207 - NASA
ORBITER FINDS POSSIBLE CAVE SKYLIGHTS ON MARS.
Excerpt: PASADENA, Calif. -- NASA's
Mars Odyssey spacecraft has discovered entrances to
seven possible caves on the slopes of a Martian volcano.
The find is fueling interest in potential underground
habitats and sparking searches for caverns elsewhere
on the Red Planet.
...Evidence that the holes may be openings to cavernous
spaces comes from the temperature differences detected
from infrared images taken in the afternoon and in the
..."Whether these are just deep vertical shafts
or openings into spacious caverns, they are entries to
the subsurface of Mars," said co-author Tim Titus
of the U.S. Geological Survey in Flagstaff. "Somewhere
on Mars, caves might provide a protected niche for past
or current life, or shelter for humans in the future."
...For additional information about Mars Odyssey and
the new findings, visit: http://www.nasa.gov/mission_pages/odyssey
- 9 July 2007. NASA
Readies Mars Lander for August Launch to Icy Site
NASA RELEASE: 07-148. WASHINGTON - NASA's
next Mars mission will look beneath a frigid arctic
landscape for conditions favorable to past or present
life. ...NASA's Phoenix Mars Lander will claw down
into the icy soil of the Red Planet's northern plains.
The robot will investigate whether frozen water near
the Martian surface might periodically melt enough
to sustain a livable environment for microbes. To accomplish
that and other key goals, Phoenix will carry a set
of advanced research tools never before used on Mars.
the water' strategy for exploring Mars has yielded
a string of dramatic discoveries in recent years about
the history of water on a planet where similarities
with Earth were much greater in the past than they
are today," said Doug McCuistion, director of
the Mars Exploration Program at NASA Headquarters,
Washington. "Phoenix will complement our strategic
exploration of Mars by being our first attempt to actually
touch and analyze Martian water -- water in the form
of buried ice."
NASA's Mars Odyssey orbiter found evidence in 2002
to support theories that large areas of Mars, including
the arctic plains, have water ice within an arm's reach
of the surface.
....Additional information on the Phoenix mission is
available online at: http://www.nasa.gov/phoenix
- February and March 2007. NSTA
WEB SEMINARS ON MARS. NASA JPL
and NSTA series of free Web seminars for 5-12 science
educators on the topic of Mars Exploration. Allow
several minutes to download/start.
- 29 January 2007. Did
Martian Meteorites Come From These Sources? By
Linda M. V. Martel, Hawai'i Institute of Geophysics
and Planetology. Excerpt: Large rayed
craters on Mars, not immediately obvious in visible
light, have been identified in thermal infrared data
obtained from the Thermal Emission Imaging System
(THEMIS) onboard Mars Odyssey. ... rays consist of
numerous chains of secondary craters, their overlapping
ejecta, and possibly primary ejecta from the source
crater. ... physical details of the rayed craters
and the target surfaces combined with current models
of Martian meteorite delivery ... lead Tornabene
and coauthors to conclude that these large rayed
craters are plausible source regions for Martian
- 25 January 2007. Mars'
Missing Air Might Just be Hiding. By Ker Than,
space.com. Excerpt: Rather than having
had its air knocked out into space, Mars might just
be holding its breath. New findings suggests the
missing atmosphere of Mars might be locked up in
hidden reservoirs on the planet, rather than having
been chafed away by billions of years' worth of solar
winds as previously thought. Combining two years
of observations by the European Space Agency's Mars
Express spacecraft, researchers determined that Mars
is currently losing only about 20 grams of air per
second into space. Extrapolating this measurement
back over 3.5 billion years, they estimate that only
a small fraction, 0.2 to 4 millibars, of carbon dioxide
and a few centimeters of water could have been lost
to solar winds during that timeframe.....
- 6 December, 2006. NASA
Images Suggest Water still Flows in Brief Spurts
ON Mars - NASA RELEASE: 06-362. WASHINGTON - NASA
photographs have revealed bright new deposits seen
in two gullies on Mars that suggest water carried
sediment through them sometime during the past seven
years. "These observations give the strongest
evidence to date that water still flows occasionally
on the surface of Mars," said Michael Meyer,
lead scientist for NASA's Mars Exploration Program,
Washington. For more information about NASA's Mars
missions, visit: http://www.nasa.gov/mission_pages/mars/news/mgs-20061206.html
- 28 July 2005 - Mars
Express images of a patch of water ice sitting
on the floor of an unnamed crater near the Martian
north pole.White patch is present all year round,
as the temperature and pressure conditions do not
favour the sublimation of water ice. It cannot be
frozen carbon dioxide since carbon dioxide ice had
already disappeared from the north polar cap at the
time the image was taken (late summer in the Martian
- 27 December 2005 Magma
and Water on Mars. By G. Jeffrey Taylor --- Martian
meteorites tell us part of the fascinating story
about when volcanoes erupted and water flowed. Lars
Borg (University of New Mexico) and Michael Drake
(University of Arizona) synthesized available age
data for Martian meteorites. Cosmochemists have determined
when a variety of Martian igneous rocks crystallized
and when their original minerals were altered by
interaction with water. Igneous events occurred soon
after the planet formed 4500 million years ago and
continued to about 174 million years ago. Water affected
the planet beginning within 100 million years of
solar system formation and continued to less than
170 million years ago, perhaps to now. These observations
tie in reasonably well with what we know from photogeologic
studies of Mars, but we need more quantitative age
determinations, implying sophisticated in situ age
measurements and sample return missions. Hawai'i
Institute of Geophysics and Planetology.
- Planetary Society News Archives on Mars -- http://planetary.org/html/news/subjectarchive/Mars-idx.html
- 28 July2005 Water
ice in crater at Martian north pole - Images
taken by the High Resolution Stereo Camera (HRSC)
on board ESA's Mars Express spacecraft show a patch
of water ice sitting on the floor of an unnamed crater
near the Martian north pole.
- 6 April 2005. NASA
RELEASE: 05-091. Durable Mars Rovers Sent into Third
Overtime Period. NASA has approved
up to 18 more months of operations for Spirit and
Opportunity, the twin Mars rovers that have already
surprised engineers and scientists by continuing
active exploration for more than 14 months.
"The rovers have proven their value with major
discoveries about ancient watery environments on
Mars that might have harbored life,"
said Dr. Ghassem Asrar, deputy associate administrator
for NASA's Science Mission Directorate. "We
are extending their mission through September 2006
to take advantage of having such capable resources
still healthy and in excellent position to continue
their adventures." The rovers have already completed
11 months of extensions on top of their successful
three-month prime missions. "We now have to
make long-term plans for the vehicles because they
may be around for quite a while,"
said Jim Erickson, rover project manager at NASA's
Jet Propulsion Laboratory, Pasadena, Calif. See also
- 2 March 2005 Mars
Exploration Rover sites zoom-in movies - From
Nick Strobel of Bakersfield College: Two Flash movies
that zoom to the very highest resolution image of
the Mars Exploration Rovers Spirit and Opportunity
from Mars orbit (Mars Global Surveyor) , from THEMIS
images and MOC narrow-angle images of the area around
Opportunity's location (Meridiani Planum). Nick created
these Flash movies for his astronomy class lecture.
Still image source material:
- 21 February, 2005, Mars
pictures reveal frozen sea. BBC News. The
find has implications for life on Mars. A huge, frozen
sea lies just below the surface of Mars, a team of
European scientists has announced. Their assessment
is based on pictures of the planet's near-equatorial
Elysium region that show plated and rutted features
across an area 800 by 900km. The team think a catastrophic
event flooded the landscape five million years ago
and then froze out.... Large reserves of water-ice
are known to be held at the poles on Mars but if
this discovery is confirmed by follow-up observations,
it would be a first for a region at such a low latitude.
..."It's been predicted for a long time that
you should find water close to the surface of Mars
near the equator," Jan-Peter Muller, from University
College London, UK, said.... Finding exposed ice
at the equator would be unlikely. Very low pressures
on the planet would lead to sublimation - the ice
would erode over time straight to water vapour. But
the research group, led by John Murray, from the
Open University, UK, tells Nature that a crust of
dust and volcanic ash, perhaps just a few centimetres
thick, has prevented this happening. "The story
runs that water flowed in some kind of massive catastrophic
event; pack ice formed on top of that water and broke
up, and then the whole thing froze rigid," explains
Professor Muller. "Large amounts of dust then
fell over that area. The dust fell through the water
and on top of the pack ice, which explains why the
pack ice is a different hue to the area around it."
- 2 December 2004. NASA Release: 04-385. Reports
Detail Rover Discoveries of Wet Martian History. The
most dramatic findings so far from NASA's twin Mars
rovers -- telltale evidence for a wet and possibly
habitable environment in the arid planet's past --
passed rigorous scientific scrutiny for publication
in a major research journal.
- 23 November 2004. Methane
in Martian Air Suggests Life Beneath the Surface.
NY Times. By KENNETH CHANG. A third
team of scientists has now reported a seemingly simple
discovery on Mars: its atmosphere contains methane.
But that finding has potentially profound implications,
including the possibility of present-day microbes
living on Mars.
- 21 September 2004 Methane on Mars causes controversy. NewScientist.com news
service, Maggie McKee. Methane and
water vapour are concentrated in the same regions of
the Martian atmosphere, say scientists studying data
from Europe's Mars Express orbiter. They say the link
may point to a common source - possibly life - but
others remain sceptical about the detection. In March,
scientists using the Planetary Fourier Spectrometer
(PFS) on Mars Express announced they had found methane
in the atmosphere at a level of just 10.5 parts per
billion. Two other groups say they have also detected
the gas with telescopes in Chile and Hawaii. Ultraviolet
sunlight takes about 300 years to destroy atmospheric
methane. These detections suggest the gas is being
replenished on Mars in the same way it is on Earth
- by processes such as geothermal heating or by life
forms, such as bacteria.
- 18 August 2004. Bedrock
in Mars' Gusev Crater Hints at Watery Past. Now
that NASA's Mars Exploration Rover Spirit is finally
examining bedrock in the "Columbia Hills," it
is finding evidence that water thoroughly altered
some rocks in Mars' Gusev Crater. Spirit and its
twin, Opportunity, completed successful three-month
primary missions on Mars in April and are returning
bonus results during extended missions. They remain
in good health though beginning to show signs of
- 6 July 2004 Detailed analyses of
Martian meteorites reveal that the planet's interior
preserves distinctive regions that formed 4.5 billion
years ago. Full story and a PDF link at: http://www.psrd.hawaii.edu/June04/martianMantle.html
- 9 June 2004 New York Times: Rover
Unearths More Evidence of Water on Mars, Scientists
Say. By JOHN SCHWARTZ. Residue
of sulfur and magnesium in a trench in concentrations
that suggest the minerals are combined as magnesium
sulfate, or Epsom salt, may mean that water percolated
through the soil.
- 6 May 2004. Mars
and the Teachable Moment. By Edna DeVore, Director
of Education and Public Outreach. The
face on Mars is a teachable moment. Turn your students
into scientists. Present the evidence for the students
to consider. There is the Viking photograph, taken
in 1976 and the Mars Global Surveyor (MGS) photographs
taken about 25 years later. Ask the students what
they see in the 1976 photograph--like everyone else,
they will see a face.... Move forward a couple of
decades. ... We have new, higher resolution photographs
of the same mesa taken by MGS and posted to the web
by Malin Space Science Systems, the designers and
builders of the camera onboard MGS. ...Send your
students there for the evidence.
- 20 April 2004. NASA RELEASE: 04-131 THE
CASE OF THE ELECTRIC MARTIAN DUST DEVILS -- Scientists
have found clues dust devils on Mars might have high-voltage
electric fields, based on observations of their terrestrial
counterpart. This research supports the vision for
space exploration by helping to understand challenges
the martian environment presents to explorers, both
robotic and, eventually, human.
- 23 March 2004, NASA RELEASE: 04-100. STANDING
BODY OF WATER LEFT ITS MARK IN MARS ROCKS. NASA's
Opportunity rover has demonstrated some rocks on
Mars probably formed as deposits at the bottom of
a body of gently flowing saltwater. "We think
Opportunity is parked on what was once the shoreline
of a salty sea on Mars,"
said Dr. Steve Squyres of Cornell University, Ithaca,
N.Y., principal investigator for the science payload
on Opportunity and its twin Mars Exploration Rover,
- 22 March 2004 NASA's M2K4 Web site's interactive
(flash) program to drive NASA's Mars Rovers, Spirit
and Opportunity, across the red planet.
- 10 March 2004. Phil Plait discusses Richard Hoaglands "Face-on-Mars."
- Jan 2004 Mars Exploration Rovers landed -- http://marsrovers.jpl.nasa.gov/ --
Briefings at http://www.cspan.org/
- 26 August 2003. HUBBLE'S
CLOSE ENCOUNTER WITH MARS
at Its All-Time Finest, By
Daniel M. Troiani
Increase in apparent size of Mars in 2003.
- 7 August 2003. Mars is Melting (NASA Science News) The
south polar ice cap of Mars is receding, revealing
frosty mountains, rifts and curious dark spots. http://science.nasa.gov/headlines/y2003/07aug_southpole.htm
- 24 July 2003. Los Alamos releases new maps of Mars
water. LOS ALAMOS, N.M. -- "Breathtaking" new
maps of likely sites of water on Mars showcase their
association with geologic features such as Vallis Marineris,
the largest canyon in the solar system. The maps detail
the distribution of water-equivalent hydrogen as revealed
by Los Alamos National Laboratory-developed instruments
aboard NASA's Mars Odyssey spacecraft.
- Mars Exploration Rover http://mars.jpl.nasa.gov/mer/ --
Launch: May/July 2003; Landing: January 2004
- 26 June 2003. JPL RELEASE: 03-216. NASA'S ODYSSEY
ORBITER WATCHES A FROSTY MARS. NASA's
Mars Odyssey spacecraft is revealing new details about
the intriguing, dynamic character of the frozen layers
now known to dominate the high northern latitudes of
Mars. The implications have a bearing on science strategies
for future missions in the search of habitats. See...Full
- 14 January 2003. Potential landing
sites for Mars Exploration Rovers are relatively
near landing sites for Viking 1 and 2, and Mars Pathfinder.
The data is from Mars Global Surveyor. http://www.jpl.nasa.gov/solar_system/features/landingsites.cfm
- 5 December 2002, Exposed Water Ice Discovered
Near the South Pole of Mars USGS Press
Release -- Surface water in
the form of ice exposed near the edge of Mars's
southern perennial polar cap has been discovered
for the first time, according to U.S. Geological
Survey (USGS) research released today in the journal
Science. There is evidence that the surface water
ice in this region may be widespread - from a half-mile
to six miles around the entire southern polar ice
cap. For more information on thermal observations
of the Mars polar region, please visit http://www.mars-ice.org
- 3 December 2002. NEW CU-NASA RESEARCH BELIES PREVIOUS
IDEA THAT MARS WAS ONCE WARM, WET PLANET. A
new study led by University of Colorado at Boulder
researchers indicates Mars has been primarily a cold,
dry planet following its formation some 4 billion years
ago, making the possibility of the evolution of life
there challenging at best. Press
Release from University of Colorado at Boulder.
- 30 October 2002. Mars opposition of 2003--Note from
Dome-L, Jean Meeus's book "Astronomical Tables of the
Sun, Moon, & Planets" does have a listing of Mars oppositions
from A.D. 0-3000. In a rapid glance
through it, there was no earlier opposition closer
than the 2003 one. However, the next closer one occurs
on Aug 28. 2287, when Mars is 55.69 million kilometers
away and the closest one over that 3000 year interval
occurs on Sep. 8, 2729, when Mars is 55.65 million
kilometers away. -- Lee Shapiro (firstname.lastname@example.org)
National Radio Astronomy Observatory
- 28 May 2002 --RELEASE: 02-99 -- ODYSSEY FINDS WATER
ICE IN ABUNDANCE UNDER MARS' SURFACE. http://mars.jpl.nasa.gov/odyssey/ and http://grs.lpl.arizona.edu.
Using instruments on NASA's 2001 Mars Odyssey spacecraft,
surprised scientists have found enormous quantities
of buried treasure lying just under the surface of
Mars-enough water ice to fill Lake Michigan twice over.
And that may just be the tip of the iceberg. "This
is really amazing. This is the best direct evidence
we have of subsurface water ice on Mars. We were hopeful
that we could find evidence of ice, but what we have
found is much more ice than we ever expected," said
William Boynton, principal investigator for Odyssey's
gamma ray spectrometer suite at the University of Arizona,
Tucson. Scientists used Odyssey's gamma ray spectrometer
instrument suite to detect hydrogen, which indicated
the presence of water ice in the upper meter (three
feet) of soil in a large region surrounding the planet's
south pole. "It may be better to characterize this
layer as dirty ice rather than as dirt containing ice," added
Boynton. The amount of hydrogen detected indicates
20 to 50 percent ice by mass in the lower layer. Because
rock has a greater density than ice, this amount is
more than 50 percent water ice by volume. This means
that if one heated a full bucket of this ice-rich polar
soil it would result in more than half a bucket of
- March 2002, A Whiff of
Vanished Martian Seas, By J. KELLY BEATTY, Sky & Telescopemagazine,
p. 18. FUTURE ASTRONAUTS ROAMING
THE SURFACE OF MARS WILL BE hard-pressed to find
sources of water, but the red planet was not always
as arid as it is now. From minuscule gullies to giant
floodplains, the face of Mars bears mute witness
to eras when water must have gushed across its surface
at least briefly.
- March 2002. Martian
Gully Mystery Solved? By DAVID TYTELL, Sky & Telescope
magazine, p. 19. PLANETARY SCIENTISTS
MAY BE (JOSE TO EXPLAINING HOW THE enigmatic little
Martian gullies formed relatively recently. According
to research published in Science Express by François
Costard and François Forget (University of
Paris) and others, changes in Mars's obliquity (polar
tilt) can easily lead to the melting of shallow subsurface
ice in just the right places.
- March 2002, Mars's Active
Snow and Ice. Sky & Telescope, p. 18. IMAGES
RETURNED BY THE MARS GLOBAL SURVEYOR (MGS) orbiter
suggest that the Martian polar caps and perhaps Mars's
entire atmosphere and climate may be surprisingly
unstable on a time scale of just a few centuries
or thousands of years. Astronomers analyzed images
of the south polar region and found ice cliffs retreating
surprisingly fast. The speed of their shrinkage,
given the temperatures and amounts of sunlight in
the region, confirms that the material is frozen
carbon dioxide (CO2). Water ice could not sublimate
(evaporate directly from solid to gas) nearly so
- 5 May 2002. Global
Surveyor images of Martian duststorms of 2001.
or see alternate
- 27 March 2002 Odyssey Serves Up Canyon Images. Now
in its final orbit, Mars Odyssey is getting to work
searching for water on the surface of the planet.
The most recent set of images returned are of a network
of channels taken by the Thermal Emission Imaging
System (THEMIS). The Nirgal Vallis is a channel 500
km long and 6 km wide at this point - astronomers
believe that gullies on the side of the channel were
formed when water erupted to the surface.For more
information, go to: http://themis.asu.edu/zoom-20020327a.html
- 11 February 2002 New Images from Mars Global Surveyor
Released -- http://www.msss.com/mars_images/moc/1yearExtend/ -- NASA's
Mars Global Surveyor began its second year of extended
operations at the beginning of February, and recently
delivered a whole new batch of images of the Red
Planet. These images were taken over course of the
spacecraft's first year of extended operations.
- 19 December 2001 -- ALL-TERRAIN ROVERS MAY SCALE
MARS' CLIFFS -- ftp://ftp.hq.nasa.gov/pub/pao/pressrel/2001/01-251.txt -- NASA
researchers are developing new prototype robots that
can drive up steep hills and descend almost-vertical
cliffs. Recent Mars Global Surveyor images suggest
water outflows near cliff edges and the possibility
of rich water-borne mineral deposits that extend
all the way to the cliff base. Working alone or as
a team, these autonomous robotic explorers may go
where no rover has gone before -- the cliffs of Mars.
- 6 December 2001 -- Mars Global Surveyor -- Mars
Orbiter Camera (MOC) Observes Changes in the South
Polar Cap: Evidence for Recent Climate Change on
Mars, Martian South Polar Pits in Layer of Frozen
Carbon Dioxide Martian Ice Caps are Eroding --New
photos taken by the Mars Global Surveyor are tracking
the changes to the Martian polar ice caps, and
from what scientists can tell, they're shrinking.
If true, this would indicate the Mars is warming
up, and it's atmosphere is becoming more dense.
In fact, if the erosion of the carbon dioxide ice
continues, some scientists predict that Mars could
become significantly warmer in just a few thousand
years. Other scientists urge caution, though, pointing
out that we don't have enough data to confirm climate
change. MGS MOC Release
- 6 December 2001 -- NASA'S
GLOBAL SURVEYOR SEES POSSIBLE CLIMATE CHANGE ON
MARS. The planet Mars we know
today is a cold, dry, desert world, but suppose
the martian climate is changing even now, year
to year and decade to decade? New observations
by NASA's Mars Global Surveyor spacecraft are expanding
understanding of the martian climate and may indicate
the climate is changing significantly even today.
- 29 November 2001. MARS
WAS ONCE ALL WET. Although
covered by frozen deserts today, Mars could have
been born with more water in proportion to its
mass than the Earth, according to new observations
from NASA's Far Ultraviolet Spectroscopic Explorer
- 9 November 2001. NASA
SELECTS 10 INVESTIGATIONS FOR 2005 MARS RECONNAISSANCE
ORBITER-- NASA today announced
the selection of 10 scientific investigations as
part of the 2005 Mars Reconnaissance Orbiter (MRO)
mission. The 2005 MRO will carry six primary instruments
that will greatly enhance the search for evidence
of water, take images of objects about the size
of a beach ball, and search for future landing
sites on the Martian surface. RELEASE: 01-220
- 29 October 2001. NASA
BULLDOZER ROVERS COULD GET THE SCOOP ON MARS --Tiny
bulldozer rovers may some day dish up the dirt
and pack it in on Mars. The scoop-and-dump design
of a prototype bulldozer rover being developed
by NASA engineers mimics that of a bulldozer and
dump truck. RELEASE: 01-208
- 11 October 2001 SCIENTISTS
TRACK "PERFECT STORM" ON MARS A
pair of eagle-eyed NASA spacecraft -- the Mars
Global Surveyor (MGS) and Hubble Space Telescope
-- are giving amazed scientists a ringside seat
to the biggest global dust storm seen on Mars in
several decades. RELEASE: 01-193
- 13 August 2001 AMES
COMPLETES SUCCESSFUL TEST OF MARS AIRPLANE PROTOTYPE
- 5 July 2001 Hubble Captures Best View of Mars
Ever Obtained From Earth http://oposite.stsci.edu/pubinfo/pr/2001/24/
- 9 May 2001. New image of a human-like face on
- 1 May 2001, Space
Weather on Mars [Science@NASA]
- 19 March 2001-- NASA's
latest mission to Mars, 2001 Mars
Odyssey, an orbiter scheduled for launch on April
7th, 2001 will seek out underground water-ice and
explore space weather around the Red Planet.
- 26 February 2001 SCIENTISTS
FIND EVIDENCE OF ANCIENT MICROBIAL LIFE ON MARS--RELEASE:
01-11AR (Ames Research Center)
- 4 December 2000 -- Evidence of Martian Land
of Lakes Discovered. http://www.msss.com/mars_images/moc/dec00_seds/
- 28 September 2000 -- 2001 MARS ODYSSEY NASA
Press release ftp://ftp.hq.nasa.gov/pub/pao/pressrel/2000/00-155.txt
- 6 June 2000 Mars
Global Surveyor -- Mars Orbiter Camera Images Suggest
Recent Sources of Liquid Water on Mars-- Gullies
seen on martian cliffs and crater walls in a small
number of high-resolution images from the Mars
Global Surveyor (MGS) Mars Orbiter Camera (MOC)
suggest that liquid water has seeped onto the surface
in the geologically recent past.
- 17 March 2000 -- Martian
Dust Devil Caught
- 10 March 2000 -- More
Surprises on Mars (Sky and
Telescope) -- 1-kilometer-square field of surface
pits (each about 2 meters deep) that give the region
of the northern polar cap a spongelike appearance.
- 9 March 2000 -- VIEW
INSIDE MARS REVEALS RAPID COOLING AND BURIED
CHANNELS (NASA Press Release)
- 8 March 2000 -- Martial
Polar Cheese -- HIGH RESOLUTION IMAGES
SHOW BIG DIFFERENCES BETWEEN MARS POLAR CAPS
(NASA Press Release) x
- 5 November 1999. Shadow of Phobos on Mars http://antwrp.gsfc.nasa.gov/apod/ap991105.html
- 10 August 1999 -- SHARPEST-EVER
MARS IMAGES REVEAL ACTIVE RED PLANET (NASA Press
- 19 May 1999 -- Hubble Views Colossal Polar Cyclone
on Mars (STScI Press Release) http://oposite.stsci.edu/pubinfo/pr/1999/22/index.html
- 29 April 1999 -- MAGNETIC STRIPES PRESERVE
RECORD OF ANCIENT MARS ftp://ftp.hq.nasa.gov/pub/pao/pressrel/1999/99-056.txt
- 25 March 1999 -- Oxygen Generation on Mars --
NASA EXPERIMENT LAYS GROUNDWORK FOR 'LIVING OFF THE
LAND' ON MARS (NASA Press Release) ftp://ftp.hq.nasa.gov/pub/pao/pressrel/1999/99-046.txt
- 22 February 1999 -- Martian Colors Provide
Clues about Martian Water (STScI Press Release) http://oposite.stsci.edu/pubinfo/pr/1999/07/
- 7 Dec 1998 -- LASER PROVIDES FIRST 3-D VIEW OF
MARS' NORTH POLE (NASA Press Release) ftp://ftp.hq.nasa.gov/pub/pao/pressrel/1998/98-219.txt
- 28 October 1998 -- NEW MARS IMAGES SHOW LAVA FLOW
PLATES AND ACTIVE DUNES (NASA Press Release) ftp://ftp.hq.nasa.gov/pub/pao/pressrel/1998/98-200.txt
- 13 March 1998 -- NEW GLOBAL SURVEYOR DATA REVEALS
DEEPLY LAYERED TERRAIN, MAGNETIC FEATURES AND GENESIS
OF A MARTIAN DUST STORM (NASA Press Release) ftp://ftp.hq.nasa.gov/pub/pao/pressrel/1998/98-045.txt
Dust Devil movies (MER Spirit)
View from orbit:
Other multimedia files at
EXPLORATION: MARS FOR EDUCATORS, NASA, 11 classroom
activities focusing on the Red Planet
Hard Copy Articles About
- Achenbach, Joel, Captured by Aliens, Astronomy Magazine,
July 2000, pp. 42-47. ...efforts to conquer space.
- Bell, Jim,Mars Pathfinder: Better Science?, Sky &
Telescope Magazine, July 1998, p. 36.
- Carr, Michael, The Proof Is In: Ancient Water
On Mars. Planetary Report, May/June
2004. The latest findings by the rover Opportunity
on the Meridiani Planum ahve confirmed the presence
on Mars of standing bodies of water at some time
in the past.
- Dobbins, Thomas, and William Sheehan, Beyond
the Dawes Limit: Observing Saturn's Ring Divisions, Sky & Telescope magazine,
Nov 2000, p. 117. Starts with a discussion of Lowell's
observations of Mars and that critics of Lowell
argued that the Dawes limit precluded the possibility
that Lowell could actually see the exceedingly
fine lines that he concluded were canals on Mars.
This article refutes those critics: resolution
for detected two point sources is considerably
different from that required to detect lines. "Harvard
astronomer, William H. Pickering, found that he
could detect a human hair at a distance of nearly
a quarter mile, when its apparent width was reduced
to only 0.03 arcsecond--1/14 the Dawes limit..."
- Dobbins, Thomas A, and Sheehan, William, The
Canals of Mars Revisited, Sky
and Telescope Magazine, March 2004, p. 114.
Recent digital images shed new light on one of
visual planetary observing's most enduring mysteries.
- Dobbins, Thomas, and William Sheehan, The Martian-Flares
Mystery, Sky & Telescope magazine,
May 2001, p. 115. Describes bright flares that
have been observed on Mars dating back to 1951.
Explanations range from natural reflections of
sunlight from Martian seas or ice to activities
of Martian inhabitants. Current thought is that
the flares are "directed reflection of sunlight
from clouds of aligned ice crystals floating in
the Martian atmosphere."
- DiGregorio, Barry, Life on Mars? 27 Years of
Questions. Sky and Telescope Magazine,
Feb 2004. p. 40.
- Graham, Rex, Missing the Mark, Astronomy Magazine,
July 2000, pp 48-53. "Several failed missions to Mars
have forced NASA into a sobering reality check."
- Hartmann, William K., Red Planet Renaissance, Astronomy Magazine,
July 2000, pp. 35-41. "Recent discoveries paint Mars
as an active planet with erupting volcanoes and underground
- Hoffman, Nick, White Mars--The Story of the
Red Planet Without Water, Mercury Magazine
(ASP), Jan-Feb, 2001 -- arguments for why the plans
to search for water on Mars may be ill-founded.
- Jakosky, Bruce M, and Mellon, Michael T. Water
on Mars. Physics Today, April 2004.
Mars is cold enough that its meager water content
appears to exist today simply in frozen and gas
phases. But as recent evidence suggests, that may
not have always been the case. Also available online
at http://www.physicstoday.org/vol-57/iss-4/p71.html but
for AGU members only
- Malin, Mike, Mars Geology Grows More Intriguing,
Astronomy Magazine, March 2001 p. 20. Mike Malin
and Ken Edgett of Malin Space Science Systems in
San Diego, ..., found what appear to be thick masses
of stratified sedimentary rock.
- Miller, Ryder W., Reflections on the 100-Year
Anniversary of The War of the Worlds: A Frontier
and Literary History of Mars, Mercury Magazine,
May-June, 1998 p. 13.
- Naeye, Robert, Red-Letter Days, Sky & Telescope Magazine,
May 2004, pp.44-48.
- Parker, Semantha, The Triumphant Turnaround
of Mars Global Surveyor, Sky & Telescope Magazine,
August 1998, p. 42.
- Tytell, David, Martian Mudflows, Sky
and Telescope Magazine, Sept. 2000, p. 56, Sky
- Zimmerman, Robert, Launching a Caravan to
Mars, Astronomy Magazine, Dec 2001,
Books About Mars