Category: Mars

NASA engineers say Opportunity’s robotic arm, which has been intermittently problematic since 2005, has worsened recently. A small motor in the shoulder joint of the Mars Exploration Rover’s arm stalled on April 14, and engineers are diagnosing the problem and assessing whether the motor can possibly be used again. They are also trying to determine the impact on Opportunity’s work if the motor were no longer usable.

The motor is one of five in the robotic arm and it controls sideways motion of the shoulder joint. The stall last week occurred after being used briefly, and after much less motion than earlier stalls. Engineers believe the problem is electrical rather than mechanical, and additional tests are being performed to determine whether the is trouble is intermittent or a permanent failure.

The arm is used to place a microscopic imager and spectrometer in contact with rocks and soils to study their composition and texture.

“Even under the worst-case scenario for this motor, Opportunity still has the capability to do some contact science with the arm,” said JPL’s John Callas, project manager for the twin rovers Opportunity and Spirit. “The vehicle has quite a bit of versatility to continue the high-priority investigations in Victoria Crater and back out on the Meridiani plains after exiting the crater.”

The two Mars rovers, Opportunity and Spirit, have been studying the Red Planet since January 2004, and each have shown some signs of aging.

When Opportunity’s shoulder motor began stalling occasionally in November 2005, engineers increased the voltage to the motor, and that allowed the motor to still be operational. Additionally, the engineering changed the standard procedure by unstowing the arm at the end of each day’s drive rather than leaving it stowed overnight. This keeps the arm available for use even if the motor then stops working.

This spring, Opportunity began crossing an inner slope of Victoria Crater to reach the base of a cliff portion of the crater rim, a promontory called “Cape Verde.” On April 14, Opportunity was backing out of a sandy patch encountered on the path toward Cape Verde from the area where the rover descended into the crater. As usual, the commands included unstowing the arm at the end of the day’s short drive. The shoulder motor barely got the arm unstowed before stalling.

“We’ll hold off backing out of the sand until after we’ve completed the diagnostic tests on the motor,” Callas said. “The rover is stable and safe in its current situation, and not under any urgency. So we will take the time to act cautiously.”

Original News Source: JPL Press Release

To truly know and understand another world, planetary scientists need to look beneath the surface of that planet. This has been done on a small scale by looking inside impact craters, a la Opportunity and Spirit on Mars. But that only provides information for one area on a big planet. To get the global picture of the subsurface, a radar sounder instrument was developed for ESA’s Mars Express spacecraft. The Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) experiment has now been successfully used for the first time to look beneath Mars’ south polar ice cap, opening up the third dimension for planetary exploration. “We have demonstrated that the polar caps at Mars are mostly water ice, and produced an inventory so now we know exactly how much water there is,” says Roberto Orosei, MARSIS Deputy Principal Investigator.

The data from MARSIS’ probe of the ice cap is still being analyzed, but scientists say they expect some surprising results to be revealed.

MARSIS is built to map the distribution of liquid and solid water in the upper portions of the Martian crust, and can investigate Mars’ subsurface up to a depth of 5 km. If reservoirs of water are detected, it will help us understand the hydrological, geological, climatic and possibly biological evolution of Mars. “At the south pole of Mars, we are seeing through ice 3.7 km thick. A small calculation shows that we could see through ice down to 20 km or more thick at Mars,” says Ali Safaeinili, MARSIS co-investigator.

No one had ever used a radar sounder from orbit on another planet before. So the team was uncertain it would work as planned. The subsurface of the planet might have been too opaque to the radar waves or the upper levels of Mars’ atmosphere (ionosphere) might have distorted the signal too much to be useful.

But, the instrument worked perfectly.

Every time a radar wave crosses a boundary between different substances, it generates an echo that the orbiter detects.

See ESA’s 3-D simulation of the radar instrument.

While MARSIS is still collecting data, a follow-up instrument is already operating at Mars. The Shallow Subsurface Radar (SHARAD) on NASA’s Mars Reconnaissance Orbiter works at higher frequencies than MARSIS and can see more details in the signals it receives from the underground layers, but it can’t penetrate the surface quite as far.

The technique’s success is prompting scientists to think of all the other places in the Solar System where they would like to use radar sounders. One obvious target is Jupiter’s icy moon, Europa. There, a radar sounder could probe the moon’s icy crust to help understand the puzzling features we see on the surface. It may even see the interface at the bottom of the ice where an ocean is expected to begin.

Asteroids and comets could be thoroughly scanned by a radar sounder, producing three-dimensional maps of their interior– perhaps exactly the data we will need if, one day, we have to nudge one out of Earth’s way. Also, this type of radar instrument could be used on our own planet to look inside Earth’s polar caps and ice sheets to determine their stability.

Mars Express has been orbiting the Red Planet since December 2003. It carries seven scientific experiments, including MARSIS, which was built by the Italian Space Agency with cooperation from JPL and the University of Iowa.

Original News Source: ESA press release

Russia has a long history of scientific discovery and space exploration through the use of animals. Beginning with space dog Laika in 1957, the space program expanded to run tests on other dogs (many returned safely to Earth) and eventually monkeys. Although the monkey testing program was stopped through lack of funding in the mid-1990’s, the nation has announced plans to send the closest relation to humans to a place where no man has gone before: Mars. And here’s us thinking it will be a human first stepping onto the Martian surface…

I must admit, I had to read the story twice before I believed it. Russia wants to send monkeys not only into space, but to Mars. I had an idea that monkeys (or more specifically macaques) were used in space missions in the past, but in my mind this was in the past and would be considered cruel in this day and age. But hold on, aren’t macaques used in medical experiments the world over anyway? Why is it so shocking that macaques should be chosen to pioneer interplanetary travel before mankind?

These questions are emotive (and controversial) and will cause much debate internationally. Many will believe that the experimental testing on animals in the ultra-modern world of space travel will seem barbaric, but there are some serious problems we might definitively answer through the use of macaque space travel. First and foremost, due to the interplanetary radiation we expect to be bathed in during a transit to Mars, by studying a macaque’s physiology during the long journey we may be able to learn how the human body will react to larger than normal doses. The fact remains, monkeys are genetically close to humans, its little wonder that we turn to them for answers.

To this end, monkeys at the Sochi Institute of Medical Primatology, at Vesyoloye near the Black Sea, have begun the selection process for the ultimate medical animal testing experiment. The institute has a long history of involvement in the Russian and Soviet space program. Sochi was the training facility for the first monkeys into space in 1983. Abrek and Bion had a five-day trip around Earth and were returned safely in Kazakhstan and rehabilitated to live “normal lives”. Two years after this historic flight, monkeys Verny and Gordy spent seven days in space. In 1987, Dryoma and Yerosha spent a record breaking (for a monkey-assisted flight) two-weeks in space. Interestingly, Dryoma was given to Cuban leader Fidel Castro as a gift. Following this, in 1989, 1992 and 1996, three two-week flights were carried out until funding for the project ran out. Now experiments have been continued on Earth to simulate weightlessness.

Now, to revitalize Sochi’s history of macaque space flight, they are beginning a two-year program to select 40 monkeys to be sent to the Institute of Biomedical Problems in Moscow so tests can be continued into aerospace biomedicine. This will culminate in a possible primate mission to Mars.

“People and monkeys have approximately identical sensitivity to small and large radiation doses, so it is better to experiment on the macaques, but not on dogs or other animals.” Boris Lapin, Institute Director.

Critics of the program are frustrated by the use of animal testing in any capacity, but remain realistic about the situation. “Humanity sacrifices more than 100 million animals a year in the name of health and beauty. It’s time to think of an alternative to experiments with animals,” says Andrei Zbarsky of the conservation group the World Wildlife Fund (WWF).

“…certainly, I feel sorry for the monkeys, they might die, but the experiments are necessary to preserve the lives of the cosmonauts who will fly to Mars in future” – Anaida Shaginyan, Institute Researcher.

This will be a controversial measure by the Russian space program and they are expecting resistance from their European partners. Although monkeys and other animals are used in medical science here on Earth, it might prove too distasteful and cruel for most, but possibly the only means to measure the physical impact on the human body after a long trip to Mars.

Source: BBC

There seems to be a never-ending flow of stunning images coming from the High Resolution Imaging Science Experiment (HiRISE) on board NASA’s Mars Reconnaissance Orbiter (MRO). In today’s high-resolution look at the Martian surface, large flat-topped hills (a.k.a. mesas) can be seen to be eroded by the Mars winds, stripping them of their material, creating sand dunes downwind. An incredible sight, it shows just how dynamic and powerful the Martian winds really are…

Imaged above the Hellespontus region of Mars, these fluid-like structures trailing across the surface are huge sand banks and sand dunes, built up after years of erosion from mesas upstream. The Mars winds have gradually stripped the large geological structures, allowing sand to build up as dunes in areas of calm. The curious crescent/droplet-shaped dune morphology indicates dominant winds blowing from west to east (left to right). As sand is carried from the mesa, it travels downstream. Where the winds begin to slack, possibly in large turbulent eddies; the suspended sand is dropped to allow dunes to grow.

The shapes of the Mars dunes bear a striking resemblance to barchan dunes, much like the ones found on Earth. The wind blows up the gentle slope of the dune, allowing sand to gradually build up. As the sand reaches a critical point, it collapses, forming a sharp slope on the downwind-facing side. Horn-like features are evident from above. In addition to the barchans, “seif”-like dunes are evident. Seifs are longitudinal stretches of sand parallel to wind direction. These are most obvious as they trail away from the mesas and stretch toward the clusters of barchan dunes.

See the entire region in a full-resolution projection.

These new images were captured on March 16th and resolve features to approximately 1.5 meters. At this level of resolution the small ripples in the wind blown sand can even be seen. To give an idea of scale, I’ve included a close up of one of the dunes. As annotated, the larger dunes are approximately 60 meters in length (from east to west) and around 40 meters in width.

Source: HiRISE

I think this will easily capture the prize for the best space photo of the month. Check out this amazing picture of Mars’ moon Phobos, captured in colour (and 3D) by NASA’s Mars Reconnaissance Orbiter.

The spacecraft snapped the picture on March 23, 2008 during a flyby. It took two separate images of the moon within 10 minutes of each other, which scientists later merged together into a stereo view.

“Phobos is of great interest because it may be rich in water ice and carbon-rich materials,” said Alfred McEwen, HiRISE principal investigator at the Lunar and Planetary Laboratory at the University of Arizona, Tucson.

Previous spacecraft, like Mars Global Surveyor, have actually flown closer to Phobos, and taken higher resolution images, but according to the researchers, “the HiRISE images are higher quality, making the new data some of the best ever for Phobos.”

When MRO took the first picture, Phobos was 6,800 km (4,200 miles) away, and it was able to resolve features as small as 20 metres (65 feet) across. For the second image, the spacecraft was 5,800 km (3,600 miles) away, and could resolve features down to 15 metres (50 feet) across.

Phobos itself is only 22 km (13.5 miles) in diameter. Since it’s so small, it doesn’t have the gravity to pull itself into a sphere, so it has an oblong shape.

Planetary scientists are hoping to understand if there are reserves of water on the surface of the Martian moon, and to get more clues about its history. Did Phobos form with Mars, or was it captured later on?

If you have a pair of red-blue glasses, you can take a look at the 3D view of Phobos on the HiRISE site. Here’s a link.

Original Source: NASA/JPL/HiRISE News Release

When the Mars Science Laboratory (MSL) goes streaking through the Martian atmosphere at more than twice the speed of sound, it’s going to need one of the largest parachutes ever used in a space mission to successfully land a car-sized rover on the Red Planet. The parachute, built by Pioneer Aerospace, has 80 suspension lines, measures more than 50 meters (165 feet) in length, and opens to a diameter of nearly 17 meters (55 feet). It is the largest so called “disk-gap-band” parachute (more on that in a minute) ever built. To get ready for the scheduled 2009 launch of MSL, engineers have begun testing different parts of the parachute in preparation for the ultimate test of the entire parachute system.

Recent successful trials of two parachute packing techniques were performed in the world’s largest wind tunnel at NASA’s Ames Research Center. Engineers loaded chutes into a cannon and fired them out at 85 mph to simulate events during the real landing, looking for damage to line attachments and other parts. All four tests were successful, and high-speed video data is now being analyzed to select a final parachute design for the mission. But the large parachute is just the beginning of the unique landing technique MSL will use.

MSL will be the first planetary mission to use precision landing techniques, using a rocket-guided entry with a heat shield to steer itself toward the Martian surface similar to the way the space shuttle controls its entry through the Earth’s upper atmosphere. In this way, the spacecraft will fly to a desired location above the surface of Mars before deploying its parachute for the final landing. MSL will use a scaled-up version of parachutes used for the Viking and Mars Exploration Rovers mission. Called a Disk-Gap-Band parachute, the name describes the construction of the parachute: a disk forms the canopy, then a small gap, followed by a cylindrical band.

The parachute is deployed using a mortar that is triggered when the vehicle reaches a fixed planet-relative velocity. The parachute is designed to survive loads in excess of 36,000 kilograms (80,000 pounds).

Twice as long and three times as heavy as the Mars Exploration Rovers, MSL is too massive to use airbags like MER. MSL’s large parachute will only be deployed 3 minutes before touchdown which should slow the incoming vehicle enough for retro rockets to fire for the final 500 meters (1,640 feet) of the descent. But after that is where it gets interesting: In the final seconds, the hovering upper stage would act as a crane, lowering the upright rover on a tether to the surface. This is first the “Sky Crane” system will be used in a space mission.

MSL, a roving analytical laboratory, will collect Martian soil and rock samples and analyze them for organic compounds and environmental conditions that could have supported microbial life now or in the past.

Original News Source: JPL Press Release