Curiosity captures images of Martian clouds

Clouds that are probably composed of ice crystals and possibly supercooled water droplets were caught in images by NASA’s Opportunity rover. 

Credit: NASA/JPL/Texas A&M/Cornell

Curiosity celebrated two years on Mars on August 5, 2014, and is continuing its progress across the surface of the planet.

The rover has already fulfilled one of its primary mission goals by confirming that environments theoretically capable of supporting microbial life were once present on ancient Mars.

Now Curiosity is continuing its journey toward the slopes of Mount Sharp and is currently headed for an outcrop dubbed 'Pahrump Hills.

In a tweet on September 2, 2014, Curiosity shared its view of the path ahead and proclaimed:

"Head for the hills! I'm driving towards these hills on Mars to do geology work & also search for clouds."

Curiosity is described as the first roving analytical laboratory on Mars, and has been cruising around the planet these past two years drilling rocks, zapping soil, and photographing layered outcrops.

The geological data that the mission has returned has been invaluable for astrobiologists trying to interpret Mars' past climate conditions but why is Curiosity also taking time to turn its instruments skyward?

Astrobiology Magazine spoke with Dr. Robert M. Haberle, Planetary Scientist at NASA Ames and a team member for the Rover Environmental Monitoring Station (REMS), and asked him why astrobiologists are curious about martian clouds.

"Clouds are part of the planet's climate system," explained Haberle. "Their behaviour tells us about winds and temperatures."

Studying weather and clouds on Mars today can shed light on processes that have shaped the planet's climate through time.

Bob M. Haberle

"Some studies suggest that clouds in the past may have significantly warmed the planet through a greenhouse effect. A warmer environment is more conducive to life," said Haberle.

Clouds are also connected to wind and weather patterns, and studying weather is important for interpreting how natural processes have shaped the rocks, dunes and outcrops that Curiosity has been photographing.

Haberle points out that, "winds are the primary mechanism for shaping the planet's surface for the past 3-4 billion years.

Studying martian weather can not only help us understand Mars' current climate, but also provides clues about its past environment and the physical processes that operate on the planet.

This information can in turn help astrobiologists interpret the planet's geological record.

REMS is an environmental monitoring station composed of six different sensors.

The instrument collects daily and seasonal data on wind, pressure, relative humidity, temperature and ultraviolet radiation at the martian surface.

REMS was contributed to the Mars Science Laboratory (MSL) mission by the the Centro de Astrobiologia (CAB) in Spain.

Nasa Mars Rover Curiosity: Wheel Wiggles but Wind Sensor is damaged

After wiggling its wheels in the Martian soil, the Mars rover Curiosity was pronounced fit to take its first test drive tomorrow.

But amidst the fanfare comes news of the rover's first science casualty.

During shakedown tests this week, the team discovered that a wind sensor on the rover's mast was damaged.

The instrument is basically an exposed circuit board attached to Curiosity's "neck" as part of the Rover Environment Monitoring Station, or REMS.

This weather station includes a suite of sensors that will measure wind speed and direction, temperature, air pressure, humidity and ultraviolet radiation throughout each day of the mission.

One of two wind sensors on REMS sent back nonsensical data. Inspections with Curiosity's cameras revealed that some of its wires are broken, and there's little hope of finding a workaround.

The team thinks the device could have been damaged in a hail of rocks during the rover's death-defying landing.

As the rover was being lowered to the ground on the Sky Crane, the plumes stirred up winds that tossed small rocks into the air. Those rocks came raining back down onto the rover's deck, where its neck-like mast was still folded down.

"Putting two and two together, we've come up with idea that some of these rocks could have fallen on the circuit boards and caused potential damage," said deputy project scientist Ashwin Vasavada in a news conference on 21 August.

"These are pretty fragile devices," Vasavada added. "That's the price we pay for flying the next generation of wind sensor."

It could have been worse. The damaged sensor was a backup, designed to get extra measurements when the wind was coming from directly behind the rover.

The other, forward-facing sensor is "working perfectly", says REMS principal investigator Javier Gomez-Elvira.

"We still have the capability to measure wind from the front, so we have almost all the capability that we had from the beginning."

Because Curiosity's nuclear power source keeps it warm at night and through the winter, REMS will give the first direct weather measurements throughout the entire Martian year, and the first measurements of a full Martian day since the Viking 1 lander stopped responding in 1982.

Monitoring the modern weather will also illuminate the planet's past. Gale Crater, where the rover landed, was carved out by wind billions of years ago, and the five-kilometre-high mountain at its centre was probably also shaped by wind.

More recently, wind sloshing back and forth in the crater's basin formed dark sand dunes that the rover will have to dodge to get to the mountain's foothills.