Caves on Mars
9/21/07
The Thermal Emission Imaging System (THEMIS) of NASA's Odyssey spacecraft
has found evidence of what look like caves on the slopes of a Martian
volcano.
The spacecraft has sent back images of very dark, nearly circular
features that appear to be openings to underground spaces. The features have
been dubbed the seven sisters --Dena, Chloe, Wendy, Annie, Abbey, Nikki and
Jeanne--after loved ones of the researchers who found them. The potential
caves were spotted near a massive Martian volcano, Arisa Mons. Their openings
range from about 330 to 820 feet (100 to 250 meters) wide, and one of them,
Dena, is thought to extend nearly 430 feet (130 meters) beneath the planet's
surface.
"They are cooler than the surrounding surface in the day and warmer at night," said Glen Cushing of the U.S. Geological Survey's Astrogeology Team and Northern Arizona University. "Their thermal behavior is not as steady as large caves on Earth that often maintain a fairly constant temperature, but it is consistent with these being deep holes in the ground."
"Whether these are just deep vertical shafts or openings into spacious caverns, they are entries to the subsurface of Mars," said USGS researcher Tim Titus. "Somewhere on Mars, caves might provide a protected niche for past or current life, or shelter for humans in the future."
More evidence for water on Mars
1/19/07
New images from the HiRISE camera aboard NASA's Mars Reconnaissance Orbiter
show astonishing details of tectonic fractures within the Candor Chasma region
of Valles Marineris. The picture on the right was taken by High Resolution
Imaging Science Experiment camera on Dec. 2, 2006. The image is approximately
1 kilometer (0.6 mile) across. Illumination from the upper left (Image
Credit: NASA/JPL/Univ. of Arizona). It shows a series of linear fractures,
called joints, that are surrounded by "halos" of light-toned bedrock.
In a paper entiteled "Fracture-Controlled Paleo-Fluid Flow in Candor Chasma,
Mars" and published in the journal Science,
Chris H. Okubo, the principal author of the paper and a postdoctoral researcher
at
the University of Arizona's Lunar and Planetary Laboratory, and his co-worker
Alfred McEwen argue that the "halos" offer clear evidence of past
fluid flow through the bedrock. These new images suggest that subsurface
fluids -- probably water, liquid carbon dioxide or a combination of the two
- once flowed abundantly in the
western Candor Chasma region of Mars.
Hirise
images Pathfinder
1/12/07
The High Resolution Imaging Science Experiment "Hiise" of NASA's
Mars Reconnaissance Orbiter has sent back very detailed images of
the 1997 landing site of NASA's
Mars Pathfinder. The pictures reveal details of hardware on the surface
and the geology of the region. Detailed images can be found at NASA Pages
and at on the website of Hirise.
Titan's
Liquid Lakes
1/3/07
Scientists report definitive evidence of the presence of lakes filled
with liquid methane on Saturn's moon Titan in this week's journal Nature cover
story. Radar imaging data from a July 22, 2006, flyby provide convincing evidence
for
large bodies of liquid on Titan. Based on the lake characteristics, Cassini scientists
think they are observing liquid-filled lakes on Titan today. Another possibility
is that these depressions and channels formed in the past and have now been filled
by a low-density deposit that is darker than any observed elsewhere on Titan.
However, the absence of wind-blown features in this area makes the low-density
hypothesis unlikely. More ...
Storm on Saturn
11/9/06
NASA'a Cassini spacecraft has observed what looks like a very large hurricane
above the south pole of Saturn. The Storm on Saturn shows one of the characteristic
features of hurricanes, a wall of tall clouds around the center. Interestingly,
the mechanism which leads to the formation of these "eye wall
clouds" on Eartch involves water: They form where moist air flows inward
across the ocean's surface, rising vertically and releasing a heavy rain
around an interior circle of descending air that is the eye of the storm
itself. Since Saturn is a gas planet, a different mechanism involving
strong convection must be involved in the formation of the hurricanle-like
storm
on Saturn.
The
observed
system
is much larger than any hurricane on Earth: It is approximately 5,000 miles
across, or two thirds the diameter of Earth. The eye wall clouds tower 20
to 45 miles above those in the center of the storm and are two to five times
taller than the clouds of thunderstorms and hurricanes on Earth. Wind speeds
reach 350 miles/hour. The storm is locked above the South Pole (hurricanes
on Eartch move). "The clear skies over the eye appear to extend down
to a level about twice as deep as the usual cloud level observed on Saturn," said
Kevin H. Baines, of Cassini's visual and infrared mapping spectrometer team
at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "This gives us
the deepest view yet into Saturn over a wide range of wavelengths, and reveals
a mysterious set of dark clouds at the bottom of the eye." The measurements
revealed that the center of the storm appears dark in a wavelength which
is absorbed by methane. More
...
Image: A swirling hurricane-like vortex at Saturn's south pole, where the
vertical structure of the clouds is highlighted by shadows. Credit:
NASA/JPL/Space Science Institute
Victoria's
Secrets
10/6/06
NASA is exploring Victoria crater on Mars from land and "air". While Mars
rover Opportunity is beginning to explore layered rocks in cliffs ringing
the
massive Victoria crater, NASA's newest eye in the
Martian sky, the Mars Reconnaissance
Orbiter, photographed the rover and its surroundings from above. The
level
of detail in the photo from the high-resolution camera will help guide the rover's
exploration of Victoria. "This is a tremendous example of how our Mars
missions in orbit and on the surface are designed to reinforce each other and
expand our ability to explore and discover," said Doug McCuistion, director
of NASA's Mars Exploration Program in Washington. "You can only achieve
this compelling level of exploration capability with the sustained exploration
approach we are conducting at Mars through integrated orbiters and landers."
"The
combination of the ground-level and aerial view is much more powerful than
either alone," said Steve Squyres of Cornell University, Ithaca, N.Y.
Squyres is principal investigator for Opportunity and its twin, Spirit. "If
you were a geologist driving up to the edge of a crater in your jeep, the
first thing you would do would be to pick up the aerial photo you brought
with you
and use it to understand what you're seeing from ground level. That's exactly
what we're doing here." More ...
Image Credit: NASA
Liquid Water on Enceladus
3/10/06
NASA's Cassini mission
has revealed that Saturn's icy moon Enceladus may have subsurface reservoirs
of liquid water. In vol 311, issue 5766 of the journal Science, scientists
describe geysers erupting from the moon's surface. Modeling
indicates that these geysers are most likely tied to liquid water
below the moons surface. The heating source that supports the
liquid water and powers the geysers is unclear: tidal heating, which creates
the liquid water oceans thought to exist below the surface of Jupiter's moon
Europa, is insufficient to work on Enceladus. More
...
"Stardust" on
Final Approach for Landing
1/14/06
NASA's Stardust mission return capsule will land Sunday, Jan. 15, at approximately
2:12 a.m. Pacific time (3:12 a.m. Mountain time) on the Utah Test and Training
Range. Stardust is completing a 2.88 billion mile round-trip odyssey to capture
and return cometary and interstellar dust particles to Earth. More ...
University of California, Berkeley is inviting Internet users
to help them search for a few dozen submicroscopic grains of interstellar dust
captured by NASA's Stardust spacecraft: http://stardustathome.ssl.berkeley.edu
Countdown
for "New Horizons" Launch to Pluto
1/11/06
Five days are left before the the first mission to the last planet nad
its moon will take off from Kennedy Space Center. The National Academy
of Sciences
has ranked the exploration of Pluto-Charon and the Kuiper Belt among the
highest priorities for space exploration, citing the fundamental scienti€c
importance of these bodies to advancing understanding of our solar system.
Different than the inner, rocky planets (like Earth) or the outer gas giants,
Pluto
is a different type of planet known as an “ice dwarf,” commonly
found in the Kuiper Belt region billions of miles from the sun. More ...
Opportunity Celebrates
One Mars Year
12/12/05
A mission planned for 90 days has turned into an adventure that's lasted
nearly two Earth years! With over four miles on her odometer, Opportunity
has returned over 58,000 images. The ground covered and the science
transported back across the void of space has helped to see into our planetary
neighbor's alluringly watery past. More
...
Image Credit: NASA/JPL-Caltech/Cornell
Discovery of Subsurface Ice on Mars
11/30/05
On 11/30/05, ESA announces that tor the first time in the history of planetary
exploration, the MARSIS radar on board ESA's Mars Express has provided direct
information
about the
deep
subsurface of Mars. First data include buried impact craters, probing of layered
deposits at the north pole and hints of the presence of deep underground
water-ice. More ...
Spirit Starts
to Climb down from Husband Hill
10/25/05
The first explorer ever to scale a summit on another planet, NASA's
Mars Exploration Rover Spirit has begun a long trek downward from
the top of "Husband
Hill" to new destinations. More ...
Image Credit: NASA
Shenzhou Lands Safely
10/16/05
China's second manned space flight has returned to earth safely.
The Shenzhou 6 spacecraft landed in Inner Mongolia early Monday morning
after orbiting the earth for five days. More ...
Expedition 12:
Third Tourist in Space
9/30/05
A Russian Soyuz rocket blasted off from the Baikonur Cosmodrome late Friday,
boosting a fresh two-man crew - and history's third space tourist - into
orbit for an Oct. 3 rendezvous and docking with the international space station.
More ...
9/29/05
Cassini flys by Saturn moons
Cassini performed back-to-back flybys of Saturn moons Tethys and Hyperion
last
weekend, coming closer than ever before to each of them. Tethys has a scarred,
ancient surface, while Hyperion is a strange, spongy-looking body with dark-floored
craters that speckle its surface. More ...
7/4/05
Deep Impact Touches Comet Temple 1
After 172 days and 431
million kilometers (268 million miles) of deep space stalking, Deep Impact
successfully reached out and touched comet Tempel
1. The collision between the coffee table-sized impactor and city-sized
comet
occurred at 1:52 a.m. EDT. More ...
6/21/05
SpaceShipOne Makes History with First Manned Private Spaceflight
The first non-governmental rocket ship flew to the edge of space today and
was piloted to a safe landing on an airport runway in the Mojave Desert. Civilian
test pilot Mike Melvill brought SpaceShipOne down to the Mojave Airport tarmac
after flying to 100 kilometers (62 miles)
in altitude, leaving the Earths atmosphere during his history-making sub-orbital
space ride. More ...
