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Nile-Like River Spotted on Saturn Moon Titan

NASA’s Cassini spacecraft has captured a crisp image of a long river cutting across Saturn’s huge moon Titan.

Image: A river near the north pole of Saturn’s moon Titan, imaged by the Cassini spacecraft on Sept. 26, 2012. The river valley stretches more than 250 miles from its ‘headwaters’ to a large sea and likely contains hydrocarbons. Credit: NASA/JPL–Caltech/ASI

The hydrocarbon-filled river stretches more than 250 miles (400 kilometers) from its source to a large sea near frigid Titan’s north pole. Cassini’s radar image is the first high-resolution shot ever taken of such a vast river system on a world beyond Earth, researchers said, and scientists are comparing it to Earth’s Nile River in Egypt.

"Though there are some short, local meanders, the relative straightness of the river valley suggests it follows the trace of at least one fault, similar to other large rivers running into the southern margin of this same Titan sea," Jani Radebaugh, a Cassini radar team associate at Brigham Young University, said in a statement.

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Curiosity Discovers Ancient Mars Lake Could Support Life

An ancient lake on Mars was capable of supporting life for tens or hundreds of thousands of years, researchers reported today based on findings from NASA’s Curiosity rover. In March, NASA announced that the lake was once capable of supporting microbial life, but little more was known. Now researchers have shown that the lake existed around 3.5-3.6 billion years ago and actually contained an “Earth-like” environment.

Not long after touching down in the Gale Crater last August, NASA’s Curiosity rover was driven over to Yellowknife Bay, a trough over 16 feet deep made up of basaltic sandstones. It’s there, near the edges of the lake where lower levels of dirt are accessible, that researchers tested to see if microorganisms could have existed. In particular, they say that chemolithoautotrophs — a type of microorganism commonly found in caves on Earth — could have existed in the lake’s environment, breaking down the area’s rocks and minerals for energy as they do on Earth.

The researchers say that liquid water once existed there, and they’ve previously speculated that it would actually have been drinkable because of its low salinity and neutral acidity level. Actual signs of microbial life haven’t been observed, but researchers say that an elemental cocktail that would have supported them was certainly present.

Full Article

Credit: NASA/JPL-Caltech

Mars Rocks Fell on Morocco, Scientists Say
→ One rock weighs more than two pounds
By Greg Wilson on NBC New York

Rocks that fell from the sky and landed in Morocco last summer came from Mars, scientists have confirmed. The meteorite chunks, including one that weighed more than two pounds, rained down in North Africa last July. A special committee of meteorite experts, including some NASA scientists, studied the rocks and determined their origin.

It is only the fifth time in history that experts have been able to confirm by chemical analysis that rocks landing on Earth came from the red planet. Astronomers believe something smashed into Mars millions of years ago and kicked up rock fragments that have been hurtling through the solar system ever since. The landscape in parts of Morocco so resembles that of Mars that rovers destined for the red planet are tested there.

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The consequences of a collision with [a small earth-crossing asteroid] are unimaginable; the repercussions would be felt the world over. In dissipating the energy equivalent of half-a-trillion tons of TNT, 100 million tons of the earth’s crust would be thrust into the atmosphere and would pollute the earth’s environment for years to come. A crater 15 miles in diameter and perhaps three to five miles deep would mark the impact point, while shock waves, pressure changes, and thermal disturbances would cause earthquakes, hurricanes, and heat waves of incalculable magnitude. Should [the asteroid] plunge into the ocean a thousand miles east of Bermuda, for example, the resulting tidal wave, propagating at 400 to 500 miles per house, would wash away the resort islands, swamp most of Florida, and lash Boston - 1500 miles away, with a 200-foot wall of water…The energy involved is the equivalent of 500,000 megatons of TNT - two orders of magnitude above that involved in the largest recorded earthquake, and four or five orders of magnitude more than Krakatoa…If the strike occurred in midocean, tsunamis in the 100-foot category would cause worldwide damage. If the strike occurred on land, the blast wave would level trees and buildings within a radius of several hundred miles, and some 10^8 tons of soil and rock dust would be thrown into the stratosphere, where for several decades it would act to reduce the solar radiation ordinarily received at earth’s surface and threaten the triggering of an ice age.

MIT Student Project in Systems Engineering, Project Icarus, MIT Press, Cambridge, Massachusetts, 1968

Mars Meteorite - NWA 998, an Orthopyroxene Nakhlite

“Another scientifically important discovery with NWA 998 is the presence of water bearing minerals within the meteorite.   This discovery strengthens the theory that Mars was once a wet planet capable of supporting life.  The other Nakhlites have evidence of being altered by flowing water but only NWA 998 contains these water bearing minerals.”

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Io’s Tvashtar Volcano In Action

This five-frame sequence of images from NASA’s New Horizons mission captures the giant plume from Io’s Tvashtar volcano. Snapped by the probe’s Long Range Reconnaissance Imager (LORRI) as the spacecraft flew past Jupiter in 2007, this first-ever movie of an Io plume clearly shows motion in the cloud of volcanic debris, which extends 330 km (205 miles) above the moon’s surface. Only the upper part of the plume is visible from this vantage point.

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Valles Marineris on Mars is the longest and deepest canyon in the Solar System. The deep gash in the side of Mars is a pretty good companion for the tallest mountain in the Solar System, Olympus Mons, which also on Mars. The pair demonstrate the world of extremes that is the Red Planet. Valles Marineris is 4,000 km long, 200 km wide at points, and up to 7 km deep. It runs along the Martian equator and covers nearly a quarter of the planet’s circumference and 59% of its diameter. The Valles Marineris system is a network of interconnected valleys that begin in the west. Noctis Labyrinthus is considered the starting point of the system, then it moves east to include the Tithonium chasmata and Ius chasmata. In the mid region are the Melas, Ophir, Coprates, Ganges, Capri, and Eos chasmata. The canyon moves through an area of chaotic terrain(ridges, cracks, and plains jumbled together)before it ends in the basin region of Chryse Planitia. One of the largest debates surrounding the area is about how it formed. In the 1970s, erosion by water and/or melting permafrost were popular theories. Liquid water can not exist in current Martian conditions, but has in the past, making the feature billions of years old. Another theory from the 1970s was that the feature formed when subsurface magma withdrew from the area. At the end of 1989, a theory emerged that it was formed by tensional fracturing. The theory most widely shared today is that it formed by rift faults and was made bigger by erosion and the collapsing of the rift walls. A rift valley is usually formed between two mountain ranges and is caused by the formation of the mountains. In this case, the formation is tied to the Tharsis Bulge. Valles Marineris is named after NASA’s Mariner 9 spacecraft, which first photographed it up close in 1971-1972. Mariner 9 was the first spacecraft to orbit another planet, just ahead of the Soviet space program’s twin missions Mars 2 and Mars 3. Valles Marineris on Mars is the focus of many astrogeologists because of its tantalizing view into the Martian geologic past. Evidence within the valley also points to a much wetter and warmer climate on Mars millenia ago. You can be sure that scientists will be looking for more clues in every set of data from the area.

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Tides of Titan Reveal Undergroud Ocean

Saturn’s largest moon Titan may have a huge subsurface ocean according to new data from NASA’s Cassini spacecraft.

"Saturn’s gravity is generating tidal forces, tugging and stretching Titan, just as (to a lesser extent) the Moon raises tides on Earth," says Cassini scientist Dr Sami Asmar from NASA’s Jet Propulsion Laboratory in Pasadena, California.

"By monitoring how much Titan is deforming, we can start to draw conclusions about the composition of its interior."

Read More via ABC Science

Image credit: A. Tavani

Watch on sagansense.tumblr.com

Curiosity Rover team members at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif., re-live the dramatic Aug. 6, 2012 landing and the mission’s achievements to date in an event aired on NASA Television and the agency’s website. In the year since inspiring millions of people worldwide with its one-of-a-kind landing in a crater on the Red Planet, Curiosity has achieved its primary scientific objective; finding evidence that ancient Mars could have sustained microbial life and has returned invaluable scientific data and images.

via NASA

This is worth every minute of your time. Join the team who made it possible (us included) and celebrate Curiosity through the eyes of the people who know her best.

Watch on skeptv.net

Mars’ North Pole Fly-Around Delivered By European Probe

Data from the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument, MARSIS. aboard ESA’s Mars Express has been used to create this animation of the Red Planets north pole. The ice cap is about 1000km in diameter (621 miles).

via Video From Space.


Dark Sand Cascades on Mars

They might look like trees on Mars, but they’re not. Groups of dark brown streaks have been photographed by the Mars Reconnaissance Orbiter on melting pinkish sand dunes covered with light frost.

Image Credit: HiRISE, MRO, LPL (U. Arizona), NASA

The above image was taken in 2008 April near the North Pole of Mars. At that time, dark sand on the interior of Martian sand dunes became more and more visible as the spring Sun melted the lighter carbon dioxide ice.

When occurring near the top of a dune, dark sand may cascade down the dune leaving dark surface streaks — streaks that might appear at first to be trees standing in front of the lighter regions, but cast no shadows.

Objects about 25 centimeters across are resolved on this image spanning about one kilometer. Close ups of some parts of this image show billowing plumes indicating that the sand slides were occurring even when the image was being taken.

Cirrus clouds on Mars.

On September 18, 2008, the Martian Lander Phoenix took a time-lapse photograph of a group of cirrus clouds moving across the Martian sky using LiDAR. Near the end of its mission, the Phoenix Lander detected more thick cirrus clouds close to the north pole of Mars. Over the course of several days, these clouds thickened, lowered, and eventually began snowing. The total precipitation was only a few thousandths of a millimeter. James Whiteway from York University concluded that “precipitation is a component of the [Martian] hydrologic cycle.” These clouds formed during the Martian night in two layers, one around 4,000 m (13,000 ft) above ground and the other at surface level. The clouds lasted through early morning before being burned away by the sun. The crystals in these cirrus clouds were formed at a temperature of −65 °C (−85 °F), and they were shaped roughly like ellipsoids 0.127 millimeters long and 0.042 millimeters wide.

Buried on the Moon

The crash of Lunar Prospector finds a quiet burial ground for astronomer Eugene Shoemaker. A small vial of Shoemaker’s ashes was loaded aboard Lunar Prospector, and now rests with the craft on the surface of the moon. He is the first person to be buried on another planet.

Shoemaker, a brilliant geologist, had hoped to be one of the astronauts who explored the moon in the early 1970’s, but was rejected because of a medical condition. He was probably most famous for proving that the huge geological depression in Arizona was actually an impact crater.

He more or less single-handedly created the field of impacts, and he was the one who started bringing to other scientists’ and the public’s attention the danger of the impacts of comets and asteroids on the Earth.

Mr. Shoemaker was involved in several U.S. space missions, including the Apollo missions — he taught the astronauts about craters before they left Earth. He and his wife Carolyn also discovered about 800 asteroids and 20 comets — including the Shoemaker-Levy 9 comet that crashed into Jupiter in 1994.

Shoemaker was killed in a car crash in 1997, during an annual trip to Australia in search for asteroid craters. He was 69.

"I don’t think Gene ever dreamed his ashes would go to the Moon," Carolyn Shoemaker said shortly before watching Lunar prospector blast-off in January 1998. "He would be thrilled."

"This is so important to us. It brings us a little closure, in a way, to our feelings. We will always know when we look at the moon, that Gene is there."

The polycarbonate capsule containing some of his ashes is one-and-three-quarters inches long and seventh-tenths inch in diameter, is carried in a vacuum-sealed, flight-tested aluminum sleeve mounted deep inside the spacecraft.

Around the capsule is wrapped a piece of brass foil inscribed with an image of a Comet Hale-Bopp, an image of Shoemaker Crater in northern Arizona, and a passage from William Shakespeare’s “Romeo and Juliet”:

And, when he shall die,
Take him and cut him out in little stars,
And he will make the face of heaven so fine
That all the world will be in love with night,
And pay no worship to the garish sun.

Lunar Prospector was launched on January 6, 1998, heading for orbit around the moon. The spacecraft has already provided Nasa geeks with global maps of the moon’s gravitational and magnetic fields, and a better understanding of the composition of the rocky neighbor of the Earth.

Scientists found traces of moon water ice lurking in a perpetually dark crater at the Moon’s south pole. Those findings led to the decision to crash the spacecraft into the crater, in an attempt to generate a plume from the impact.

Source: Geekculture.com

Watch on skeptv.net

Planetary Scientist Profile: Brent Garry

NASA Geologist Brent Garry discusses his work studying volcanoes and lava flows on the Earth, the Moon, and Mars.

This video is public domain and can be downloaded at:
http://svs.gsfc.nasa.gov/vis/a010000/a011300/a011304

via NASA explorer.


Venus in 3D

NASA’s Magellan probe mapped almost the entire surface of Venus during its four-year mission in the early 1990s. Because of the thick clouds that entirely hide the planet’s surface, the probe could not take traditional photographs of the surface. Instead, it scanned the planet in long strips using a method called synthetic aperture radar, which allows for high-resolution images to be made even with a relatively small antenna.

Credit: NASA/JPL/USGS, anaglyph by P. Grindrod (UCL)

The spacecraft also recorded data about the elevation of the surface, and by combining this with the radar images, scientists are able to produce 3D models of the planet’s surface.

Because the surface of Venus is relatively flat, the elevation in these images is multiplied by 10, to make the contours of the landscape more visible.

UCL’s Earth Sciences department is home to one of NASA’s Regional Planetary Image Facilities - the only one of its kind in the UK - and has a full collection of these Magellan images, and the equipment required to view them. However, viewing them has until now required a bulky stereoscope and careful alignment of the images - not to mention making an appointment to visit the archive.

This new anaglyph of one of the Magellan images lets you see the 3D structure on your computer screen without the need for bulky equipment: simple and cheap red/cyan 3D glasses are all you need.

New Observation sheds light on amazing Mars Cavern

"From a second observation, creating a stereo pair, we now know the topography much better. From the characteristic angles of the slopes, it looks like loose granular material has drained into a cave (probably a lava tube in an area like this).

This is a conical collapse pit (approximately 50 meters or 165 feet deep) implies a conical pile of debris of equal height sitting in the cave and the top of this pile is (approximately 30 meters or 100 feet) below the rim of the hole. So this is a pretty enormous cave.: approximately 80 meters or 265 feet from floor to ceiling!”

Panguite thought to be oldest mineral in the solar system

In 1969 a meteorite fell to earth in the state of Chihuahua. The Allende meteorite serves the scientific community to today as a great source of information on the evolution of the solar system.

“Panguite is an especially exciting discovery since it is not only a new mineral, but also a material previously unknown to science,” says Chi Ma, a senior scientist and director of the Geological and Planetary Sciences division’s Analytical Facility at Caltech and corresponding author on the paper.

“The intensive studies of objects in this meteorite have had a tremendous influence on current thinking about processes, timing, and chemistry in the primitive solar nebula and small planetary bodies,” says coauthor George Rossman, the Eleanor and John R. McMillan Professor of Mineralogy at Caltech.

According to Ma, studies of panguite and other newly discovered refractory minerals are continuing in an effort to learn more about the conditions under which they formed and subsequently evolved. “Such investigations are essential to understand the origins of our solar system,” he says.

Image via Caltech

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