Science


Looks like heavy traffic over the holidays on Mars. Like jet trails in the sky, the Mars dust looks like it holds the memories of many vehicles running through it. As the jet trails evaporate in the atmosphere, so will the Rover trails in the dust as the wind eventually fills them up with new dust.

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Both Spirit and Opportunity are nearing milestones. Spirit landed on Mars on January 3, 2004, with Opportunity landing 21 days later. If I recall correctly, the originally mission was hoped to last 90 days. Both have lasted about 20 times longer.

Guess what? They’re still working. My car can’t go six months without something going wrong with it and me taking it into the shop. I predict in the future we will all be driving Rovers on Earth. Better than golf carts, surely; great mileage and no maintenance.

The Martian wind has helped clear the dust from the rovers solar panels that collect sunlight and convert it into energy. These puppies don’t have antifreeze either. My car battery would have died in this cold long, long ago.

Admittedly, Spirit just barely survived this Martian winter. Still, both seem to be in good condition for the foreseeable future, which is simply marvelous.

Plans call for Spirit to check out “Home Plate”, an area of explosive volcanic material that scientists are eager to look over. Opportunity will head to Endeavour Crater.

Remember the excellent Inspector Morse tv series and the wonderful books written by Colin Dexter? Everyone just called him ‘Morse’. Not revealed until one of the last episodes was his first name – Endeavour.

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Infrared Images of Saturn’s Poles

NASA’s Cassini spacecraft has taken new pictures showing a giant cyclone at Saturn’s north pole and its south pole, the latter apparently powered by Earth-type storm patterns.

The characteristics of these cyclones differs from Earth-based cyclones in interesting ways.

The north pole cyclone is only visible in the near-infrared wavelengths due to winter in that region of Saturn. At these wavelengths, seven times greater than that of visible light, the clouds deep inside Saturn’s atmosphere are only seen in silhouette against the background radiation of Saturn’s internally generated heat.

Saturn's South Polar Region Revealed

An infrared map of the north pole of Saturn has been created showing features as small as 120 km (75 mi) visible. The whirlpool-like cyclone there is rotating at 530 km/hr (325 mph), more than twice as fast as the highest winds measured in cyclones on Earth.

This cyclone is surrounded by a honeycombed-shaped hexagon, which itself does not seem to move while the clouds within it whip around at high speeds, also greater than 500 km/hr (300 mph). Neither the fast-moving clouds inside the hexagon nor this new cyclone seem to disrupt the six-sided hexagon.

Hurricanes on Earth are fueled by the ocean’s heat and water while Saturn’s cyclones have no body of water at their bases as Saturn’s hurricanes are locked to the planet’s poles, whereas terrestrial hurricanes drift across the ocean.

Just as condensing water in clouds on Earth powers hurricane vortices, the heat released from the condensing water in Saturn’s thunderstorms deep down in the atmosphere may be the primary power source energizing the vortex.

At the southern pole, the new infrared images of the pole, under the daylight conditions of southern summer, show the entire region is marked by hundreds of dark cloud spots. The Yet Yawning Gulf

The clouds, like those at the north pole, are likely composed of ammonium hydro-sulfide with possibly a mixture of other materials from below. Conversely, most of the hazes and clouds seen on Saturn are believed to be composed of ammonia, which condenses at higher and more visible altitudes.

The solar wind is a gas plasma blown off the surface of our sun at a million miles per hour. It is the outer atmosphere of the sun expanding out into space in all directions all the time. It effectively forms a shield around our solar system like a bubble that is called the heliosphere that tends to reflect harmful cosmic rays originating from other star systems, basically pushing away the rest of the galaxy from our solar system. This outward flow of particles is constant and creates outbound pressure referred to as a wind, a solar wind.

Sometimes it is stronger than at other times. Apparently, it is also sometimes weaker, as new data suggest.

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An image of the sun taken Sept 25 using the SOHO observatory’s Extreme ultraviolet Imaging Telescope at 304 Angstrom. SOHO, NASA/ESA

This is perplexing. The strength of the wind forms a pressure barrier that repels the intergalactic cosmic radiation, which is quite harmful to life, especially life floating around in space, space stations and spacecraft. Earth is protected by its magnetosphere and by its atmosphere for two additional tiers of protection. Spacecraft orbiting the Earth would also be protected by its magnetosphere. Spacecraft en route to the moon would have minimal protection.

The spacecraft Ulysses launched in October 1990, is a mission out of the plane of the planets orbiting the polar regions of the sun. Ulysses has detected a gradual decrease in the solar wind over the last 15 years equal to nearly 25%.

A segment today on Science Friday, talks to David McComas, Principal Investigator for Solar Wind Observations over the Poles of the Sun (SWOOPS) Experiment, about the solar wind and the findings by the spacecraft Ulysses. The archived podcast should be available later today here.

The Ulyssess/SWOOPS web site is here: http://swoops.lanl.gov/ .

Al? Found your telescope; it’s back here in the storage shed.

The telescope goes on display this week after being forgotten for decades. Restorers spent three years and $10,000 spent refurbishing it.

An old reflecting telescope that still works well enough to see five of Jupiter’s moons and surface stripes, it was found in a Jerusalem storage shed.

Einstein received the telescope in 1954, the year before he died as a gift from a friend named Zvi Gizeri, who apparently made it himself. It will be on display beginning Thursday at Hebrew University. Einstein willed his records to the school he helped co-found.

The long black tube about eight inches in diameter and 6 feet long stands on a base experts say may have been taken from the German army. It was this unique base, recognizable in a picture of Einstein with the telescope, and a signature from Gizeri on one of its mirrors, that confirmed its authenticity in 2004, when a biologist named Eshel Ophir made the connection.

The telescope was discovered in a storage shed in the late 1990s by a computer specialist at Hebrew University, however, he did not recognize it as Einstein’s, and left it in the shed.

Ophir made the connection accidentally, mistaking another forgotten telescope for the famous physicist’s. After searching through the archives and photos, Ophir realized the real Einstein telescope was actually the one his colleague had found unceremoniously years earlier. Ophir said he immediately took the telescope to the university’s Meyerhoff Youth Center to protect and clean it.

With the exception of a new eyepiece, the rest of the device, from lenses to optics, is original. Eisnstein likely used the telescope for recreation and not for professional purposes.

Science Friday http://www.sciencefriday.com/ has an excellent update on the Mars science program and planned projects for Mars. They also discuss possible missions in the next 5 to 10 years. The podcast should be available later today here: http://www.sciencefriday.com/feeds/about/.

Here’s the description of the segment from their web site:

In this segment, we’ll get the big picture on science on the planet Mars. From orbiting observatories to roving rovers to the ditch-digging Phoenix — what have planetary scientists learned about Mars, and what remains to be discovered?


The most recent visitor to the Red Planet is NASA’s Phoenix Mars Lander, which launched in August 2007 as the first mission in NASA’s Scout Program. Phoenix is designed to study the history of water and habitability potential in the Martian arctic’s ice-rich soil. So far, the lander has identified water ice in soil samples, and has detected the chemical perchlorate in the soil, a sign of the presence of liquid water in the past.


The Phoenix Mars Lander joins the twin rovers of the Mars Exploration Rover project, Spirit and Opportunity, which have been in operation since 2004. Now running years past their planned lifetime on Mars, the rovers are still exploring the surface. Rover Opportunity recently exited the Victoria Crater after several months on the crater floor.


Several orbiting observatories, including Mars Odyssey, Mars Express, and Mars Reconnaissance Orbiter are examining the different aspects of the planet from above. The orbiting platforms have studied the planet’s atmosphere, mapped its surface, and are also supporting the ground-based exploration missions.


We’re broadcasting this week from Tucson, Arizona, home base for NASA’s Phoenix Mars Lander, as guests of Arizona Public Media.”

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Image: NASA’s Mars Exploration Rover Opportunity climbed out of “Victoria Crater” following the tracks it had made when it descended into the half-mile-diameter bowl nearly a year earlier.

Forgetting for a moment the extreme cold and harsh environment on Mars, the pictures that the Phoenix lander is transmitting back to Earth are marvelous in their ordinariness. The pictures could be soil at many if not most any place on Earth. They’re awesome due to their clarity and resolution, making one feel like they could walk out their back door and pick up a handful of Martian dirt. No big whoop at all.

Analysis has started on a sample of soil delivered to NASA’s Phoenix Mars Lander’s wet chemistry experiment from the deepest trench dug thus far. Additionally, Phoenix has also been observing movement of clouds overhead.

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Its robotic arm recently sprinkled a small fraction of the estimated 50 cubic centimeters of soil that had been scooped up from the informally named “Stone Soup” trench on Saturday, the 95th day of the mission. The Stone Soup trench, in the left portion of the lander’s active workspace, is approximately 18 centimeters (7 inches) deep.

The surface of the arctic plain where Phoenix landed on May 25 bears a pattern of small polygon-shaped hummocks, similar to some permafrost terrain on Earth. This is why scientists thought this area ideal to point the lander to. They are particularly interested in the new sample because it is from a trench on the border between two of the polygons, where different material may collect than what has been analyzed from near the center of a polygon. From inside Phoenix’s scoop, the sample material from the bottom of the trench displayed clumping characteristics somewhat different from other cloddy soil samples that have been collected and examined. There are clumps and then there are clumps.

Some clues to the composition of the sample has been derived from images taken. While spectral observations have not produced any sign of water-ice, bigger clumps of soil have shown a texture consistent with elevated concentration of salts in the soil from deep in the trench. The lander’s wet chemistry laboratory can identify soluble salts in the soil.

The science team has also been studying a series of still pictures of the nearby Martian sky showing dramatic water ice clouds moving over the landing site during a 10-minute period on Sol 94 (Aug. 29).

“The images were taken as part of a campaign to see clouds and track wind. These are clearly ice clouds,” said Mark Lemmon, the lead scientist for the lander’s surface stereo imager, from Texas A&M University.

Image: NASA

The Mars rover Opportunity is making its way back out to the Martian plains nearly a year after descending into a large Martian crater, Victoria, to examine exposed ancient rock layers.

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“We’ve done everything we entered Victoria Crater to do and more,” said Bruce Banerdt, of NASA’s Jet Propulsion Laboratory in Pasadena, California who is project scientist for Opportunity and its rover twin, Spirit.

Opportunity is now preparing to look at loose cobble rock on the plains which are approximately fist-size and larger, which were thrown long distances when objects hitting Mars blew deep craters into the planet; even deeper than the recently explored Victoria crater.

“Our experience tells us there’s lots of diversity among the cobbles,” said Scott McLennan of the State University of New York, Stony Brook. McLennan is a long-term planning leader for the rover science team. “We want to get a better characterization of them. A statistical sampling from examining more of them will be important for understanding the geology of the area.”

Opportunity entered Victoria Crater on Sept. 11, 2007, after a year of exploring from the rim. Once a drivable inner slope was identified, Opportunity used contact instruments on its robotic arm to inspect the composition and textures of accessible layers, then drove close to the base of a cliff called “Cape Verde,” part of the crater rim, to capture detailed images of a stack of layers 20 feet tall. The information Opportunity has returned about the layers in Victoria suggest the sediments were deposited by wind and affected by groundwater.

“The patterns broadly resemble what we saw at the smaller craters Opportunity explored earlier,” McLennan said. “By looking deeper into the layering, we are looking farther back in time.” At approximately a half mile in diameter, it is the deepest seen by Opportunity.

Engineers are programming Opportunity to climb out of the crater at where it entered. A spike in electric current drawn by the rover’s left front wheel last month settled debate about whether to keep trying to get closer to the base of Cape Verde on the steep slope. The spike resembled one seen on Spirit when that rover lost the use of its right front wheel in 2006. Opportunity’s six wheels are all still working after 10 times more use than they were designed to perform, but the team took the spike in current as a reminder of the pitfalls involved. Yet, unbelievably, the rover is still working well.

“If Opportunity were driving with only five wheels, like Spirit, it probably would never get out of Victoria Crater,” said JPL’s Bill Nelson, a rover mission manager. “We also know from experience with Spirit that if Opportunity were to lose the use of a wheel after it is out on the level ground, mobility should not be a problem.”

Opportunity drives with its robotic arm out of the stowed position because a shoulder motor has degraded over the years to the point where the rover team didn’t want to risk having it stop working while the arm is stowed on a hook. If the motor were to stop working with the arm unstowed, the arm would remain usable; not a good thing.

“Both rovers show signs of aging, but they are both still capable of exciting exploration and scientific discovery,” said JPL’s John Callas, project manager for Spirit and Opportunity.

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