Category: Missions

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Malea Patera isn’t the name of one of the One Hundred and One Dalmatians, but it is the designation of an ancient volcano on Mars located on the outskirts of the Hellas impact basin. This isn’t your typical Martian landscape — just where are the red rocks and soil? — but is reminiscent of the markings on a Dalmatian dog. So what is going on here? This image was taken in early spring for this location in the southern hemisphere and the ground is covered with bright frost except for some dark splotches found in discrete patches. This is where the sunlight has penetrated the frost and initiated defrosting around discrete spots. The HiRISE scientists say that clearly, something is different about the patches, with the defrosting taking place, while the other areas remain frosty. One possibility is that these are (frost covered) dark sand dunes that heat up more easily than the surrounding terrain. However, to find out for sure, HiRISE will need to take a new image in the summer time to really know what is happening here. See below for a full view of this region, plus a few more of a mega-huge batch of images that were released today from the HiRISE camera on the Mars Reconnaissance Orbiter.

We move from dogs to spiders, but this, too is an unusual Mars image. Mars’ seasonal cap of carbon dioxide ice (dry ice) has eroded to create many beautiful terrains as it sublimates every spring. In this region we see troughs that form a starburst pattern.

In other areas these radial troughs have been referred to as “spiders,” simply because of their shape. In this region the pattern looks more dendritic as channels branch out numerous times as they get further from the center. The troughs are believed to be formed by gas flowing beneath the seasonal ice to openings where the gas escapes, carrying along dust from the surface below. The dust falls to the surface of the ice in fan-shaped deposits.

HiRISE spied the Opportunity rover heading through the dunes of Meridiani Planum. This image is about 400 meters across and was taken on January 29, 2009, Opportunity’s 1783rd sol (Mars day) on the Red Planet. Opportunity had driven 130 meters on the previous sol; wheel tracks are visible crossing dark ripples to the upper right of the rover. The ripples, which trend mostly north-south in this area, can be easily crossed by the rover unless they are very large (such as those right of center).

Using the HiRISE images allows the MER scientists to plan out Oppy’s route in great detail, avoiding potential hazards and targeting features of interest (such as the small craters below and left of center). HiRISE images are routinely used by the Opportunity operations team for these purposes, and to plan the route to distant Endeavour Crater, the long-term goal of Opportunity’s mission, about 17 km to the southeast.

Opportunity has been exploring Mars for over 5 (Earth) years; it will probably take another two years to reach Endeavour.

Check out over 600 observations that were just released by the HiIRISE team — 2 terabytes worth of data! And all are Martian eye candy (or is that “Hi” candy?) Hats off to HiRISE and her team!

Source: HiRISE site

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The two Mars Exploration Rovers have both seen their fair share of craters in their five years on Mars. Opportunity is currently booking it across Meridiani Planum on her way to Endeavour Crater, an ancient, huge hole in the ground (22 kilometers (13.7 miles across). But recently she came across the youngest crater either rover has ever seen. This crater is “young,” in relative terms; scientists say this small crater called “Resolution” formed sometime in the past 100,000 years. Most features studied by Opportunity are much older, including rocks over 3 billion years old. In contrast to these seniors, Resolution is just a baby.

Unlike a baby’s soft skin, a newborn crater starts out sharp, and only softens over time. As craters age, the “sandblasting” action of the Martian wind erodes rocks ejected during crater formation and fills its bowl with sand. Signs of this crater’s youth are fresh rocks on the crater rim and an empty bowl. The newer crater also drapes over older surrounding dunes. Finding youth pays off: scientists can compare Resolution to older craters to learn how fast wind changes the Martian surface over time.

In other rover news, Spirit has received a boost of power from a wind cleaning event. Rover driver Scott Maxwell shared via Twitter that Spirit’s current energy output is up to 371 watts/hour per sol. This is up from less than 250watts/hour in January. Maxwell said Spirit’s solar panels are the cleanest they’ve been in 550 sols. That’s good news, because Spirit needs all the energy she can get, with trying to battle some recent issues with memory problems.

The image above is Spirit’s current view, with a mound in the upper left called “Von Braun” that is the rover’s possible investigation site in future months. From the location where Spirit was when the image was taken, Von Braun is about 160 meters (525 feet) away.

Source: JPL

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Wow – what a shot by Mars Express! Mars has several regions of what is called ‘chaotic terrain’. These are areas with large accumulations of rocks of varying sizes, as well as flat-topped features. These erratically shaped rocks are large, too: between 1-10 km in size. Some chaotic terrain on Mars is thought to form when there is a sudden removal of subsurface water or ice, causing the surface material to slump and break into blocks. The region shown here, however — Ariadnes Colles — is not a water-source region, so scientists are still debating whether Ariadnes Colles was formed by the action of water or wind. Either way, this is a very interesting region. See below for a straight on view that’s just as incredible.

A large impact crater, 1200 m deep, is visible on the right, which has a smaller crater inside of it. The larger crater is about 30 km in diameter and covers an area roughly the size of Hamburg, Germany. The smaller younger crater lies almost at the center of the older one, and has a diameter of just 10 km.

Interestingly, the blocks, or mesas have a striking lineation, as almost all are oriented in the northwest-southeast direction. By looking at the larger versions, it’s possible to see the northwestern flanks have been eroded more strongly than the opposing southeastern ones.

Some slopes of the flat-topped mesas have been covered by darker material, likely sand or volcanic ash that was blown up on the slopes.

Anyone ready to visit this interesting region?

Source: ESA

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Poor Spirit. She’s getting old, arthritic and forgetful. The “oldest” of the two Mars Exploration Rovers had another bout of what engineers from JPL are calling “amnesia.” About a week ago, she experienced some unexpected reboots of her computer. Then, she had three good days in a row, completing Earth-commanded activities without incident. But then on April 17 and 18, she became forgetful – she failed to record data into her flash memory (where information is preserved when Spirit is powered down) and rebooted herself again. The last reboot put Spirit into autonomous operation in which the rover keeps itself healthy, and engineers are running diagnostics to try to regain control of the rover.

“We are proceeding cautiously, but we are encouraged by knowing that Spirit is stable in terms of power and thermal conditions and has been responding to all communication sessions for more than a week now,” said JPL’s Sharon Laubach, chief of the rover sequencing team, which develops and checks each day’s set of commands.

Engineers operating Spirit are investigating the reboots, and trying to determine if the amnesia events are related to the reboots. Spirit has had three of these amnesia events in the past 10 days, plus one on Jan. 25. No causal link has been determined between the amnesia events and the reboots.

Engineers have found ways to cope with various symptoms of aging on both rovers. The current diagnostic efforts with Spirit are aimed at either recovering undiminished use of the rover or, if some capabilities have been diminished, to determine the best way to keep using the rover.

Laubach said, “For example, if we do determine that we can no longer use the flash memory reliably, we could design operations around using the random-access memory.” Spirit has 128 megabytes of random-access memory, or RAM, which can store data as long as the rover is kept awake before its next downlink communications session.

During the past week of diagnostic activities, the rover has successfully moved its high-gain dish antenna and its camera mast, part of checking whether any mechanical issues with those components may be related to the reboots, the amnesia events, or the failure to wake up for three consecutive communication sessions two weeks ago.

Spirit and her twin, Opportunity, have been on Mars since 2004. Spirit’s right front wheel is stuck, and so she now drives backwards and drags the crippled wheel behind. The top image shows how the wheel is dragged through the Martian regolith.

Source: JPL

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Just like hurricane season or tornado season on Earth, Mars has stormy seasons, too. However, the Red Planet has dust storms, and they can be whoppers, which is bad news for the two Mars rovers, Spirit and Opportunity who rely on clear skies and sunshine for power. On April 21, Mars will be at the closest point to the sun in the planet’s 23-month, elliptical orbit. One month later, the planet’s equinox will mark the start of summer in Mars’ southern hemisphere. This atmospheric-warming combination makes the coming weeks the most likely time of the Martian year for dust storms, and given the current forecast based on data from the orbiting Mars Reconnaissance Orbiter and Mars Odyssey, these storms could be severe enough to minimize activities of the rovers.

There are several instruments on the orbiters that can monitor the weather patterns on Mars. The Mars Color Imager camera on Mars Reconnaissance Orbiter sees the entire planet every day at resolution comparable to weather satellites around Earth. Two other instruments — the Thermal Emission Imaging System on Mars Odyssey and the Mars Climate Sounder on Mars Reconnaissance Orbiter — monitor changes in airborne dust or dust-related temperatures in Mars’ upper atmosphere.

According to an article by Emily Lakdawalla at the Planetary Blog, the Climate Sounder is seeing temperatures in Mars southern hemisphere warm up rather dramatically, and even staying warmer than usual during the night. So far, however, the warming is staying south of the equator region where the rovers are.

The air has been relatively clear for several months on Mars, but in March increased haze reduced Spirit’s daily energy supply by about 20 percent and Opportunity’s by about 30 percent. Widespread haze resulted from a regional storm that made skies far south of the rovers very dusty. Conditions at the rovers’ sites remained much milder than the worst they have endured. In July 2007, nearly one Martian year ago, airborne dust blocked more than 99 percent of the direct sunlight at each rover’s site.

To supplement the orbiting assets looking down on Mars and the rovers, Spirit and Opportunity point cameras toward the sun to check the clarity of the atmosphere virtually every day. These measurements let the planning team estimate how much energy the rovers will have available on the following day.

“We can identify where dust is rising into the atmosphere and where it is moving from day to day,” said Michael Malin of Malin Space Science Systems, San Diego, principal investigator for Mars Color Imager. “Our historical baseline of observing Martian weather, including data from the Mars Global Surveyor mission from 1998 to 2007, helps us know what to expect. Weather on Mars is more repetitive from year to year than weather on Earth. Global dust events do not occur every Mars year, but if they do occur, they are at this time of year.”

Winds that can lift dust into the air can also blow dust off the rovers’ solar panels. Opportunity just benefited from a blast of wind the first week of April and Spirit got to minor cleanings in February. “We’re all hoping we’ll get another good cleaning,” said rover chief engineer Bill Nelson from JPL.

Unexplained computer reboots by Spirit in the past week are not related to dust’s effects on the rover’s power supply, but the dust-storm season remains a concern. Spirit received commands Tuesday to transmit more engineering data in coming days to aid in diagnosis of the reboots.

Well keep an eye on the spacecraft keeping an eye on Mars and provide updates during dust storm season on Mars.

Sources: JPL, Planetary Blog