March 27, 2015

This week, the rover Opportunity reached 26.2 total miles of travel on Mars, the Martian equivalent of an earthling marathon. The rover’s 0.00027-mile-per-hour average pace would not set any records on this planet, but Opportunity holds the record for the first (and only) marathon completed off Earth. Eleven years and two months is the time to beat.

NASA’s Opportunity rover appears in this computer-generated image. Credit: JPL/NASA

Opportunity is one of two identical probes sent to Mars in 2003 as part of the Mars Exploration Rover Mission to study the history of water on the planet. Engineers and scientists at the Jet Propulsion Laboratory designed and built the rovers for the United States National Aeronautics and Space Administration (NASA). Opportunity carries instruments created by teams of scientists and engineers from across the United States and Europe. The two rovers have helped scientists learn that water existed on the surface of Mars billions of years ago and that this water might have provided a suitable habitat for life.

Opportunity has traveled farther than any other off-Earth ground vehicle, including the piloted lunar rovers used in some of the Apollo missions. In July 2014, Opportunity broke the previous off-Earth record of 24.2 miles set in 1973 by the Soviet lunar rover Lunokhod 2.

Opportunity’s marathon shows just how tough and long-lived the little rover is. Opportunity and its twin Spirit were originally designed for 90-day missions. But they both continued to gather information on the surface of Mars long after that. Opportunity has powered through rugged terrain and age-related equipment problems to gather important information about the history of water on the Red Planet. This year, scientists worked to bypass a memory problem that caused the rover to “forget” the data it collected before sending it back to Earth.

Other World Book articles:

• Mars Pathfinder
• Mars Science Laboratory
• Astronomy (2004) (a Back in Time article)
• The Search for Water on Mars (a Special Report)

January 27, 2014

Opportunity, the hardy Mars rover that was expected to operate for just 90 days, has marked its 10th anniversary on the red planet. Even more amazingly, the rover, part of the Mars Exploration Rover Mission, is still revealing new information about Mars. NASA launched Opportunity and its twin, Spirit, in 2003 to study the history of water on the red planet. Their  90-day mission, which began in 2004, turned out to be merely a warm-up. Both rovers continued to gather information without any major setbacks for more than five years.

While traversing Mars, the rovers found evidence of ancient hot springs and thermal vents, the first meteorite ever discovered on another world, and rocky spheres created from water-bearing minerals. With Spirit, Opportunity also took the first photos of Earth-like clouds in the Martian sky from the planet’s surface. In early 2009, Spirit became permanently trapped in a bed of loose soil. NASA ended that rover’s mission in 2011. But Opportunity rolled on. The rover has now clocked up about 24 miles (38.7 kilometers) and taken 170,000 photographs.

Opportunity on Mars, in an artist's illustration. (Courtesy NASA/JPL-Caltech)

The rover’s latest discoveries involve rocks dated to about 4 million years ago, the oldest ever discovered by the rover. Opportunity’s analysis of the rocks has provided more evidence for than the surface of Mars was once  warmer and wetter than scientists had thought. Moreover, the rocks formed in water that was less acidic—and thus, more hospitable to microbial life—than the rocks analyzed previously by the rover.

Additional World Book articles:

• Mars Pathfinder
• Mars Science Laboratory
• Space exploration
• The Search for Water on Mars (a special report)

December 19, 2013

The Mars Science Laboratory, nicknamed Curiosity, has made a number of remarkable discoveries since it landed on Mars in the summer of 2012. The most recent feather in the rover’s cap is the discovery of a primordial lake within Gale Crater, the landing site of the small vehicle. Unlike previous evidence of liquid water on the planet, this new finding, in an area called Yellowknife Bay, hints of water similar to the liquid fresh water found on Earth. The new discovery paints the surface of Mars as a much more inviting environment for life as we know it to form. The water in the lake appears to have been both long standing and neither too acidic or alkaline for life as we know it.

The lake seems to have been relatively large and may have remained on the planet for thousands of years, if not more. Furthermore, the water seems to have been present around 3.5 billion years ago, about the same time scientists think life began on Earth. The discovery of the lake also reinforces the findings that what look to be stream beds, channels, deltas, and other landforms on the planet were created by water and are exactly what they appear to be.

The possible extent of an ancient lake inside Gale Crater is shown in an illustration superimposed on a satellite photo. The possible extent of the lake was estimated by mapping ancient lake and stream deposits and recognizing that water flowed from the crater rim into the basin (arrows). The water would have pooled in the linear depression created between the crater rim and Mt. Sharp (center of crater). The area’s history likely included the coming and going of multiple lakes of different sizes as climate conditions evolved. (NASA/JPL-Caltech/MSSS)

The most thrilling discovery to come from the exploration of the planet would surely be the discovery of life, whether the life existed in the past or is currently still thriving. Although the planet has since dried out and the atmosphere nearly vanished, some scientists believe the planet could still harbor life under the planet’s surface. Further exploration is needed to confirm this hope. There has even been talk for many years of the possibility that life on Earth was carried here by meteorites that originated on the Martian surface. Many meteorites came from Mars. Did they they carry some of the building blocks for life to Earth? Did they actually carried life itself as tiny passengers?

Additional World Book articles:

• Probing the Planets (a special report)
• The Search for Water on Mars (a special report)
• Space exploration 2011 (a Back in Time article)
• Space exploration 2012 (a Back in Time article)

May 23, 2013

Opportunity, the hardy Mars rover that has been exploring the red planet since 2004, has now driven farther on an extraterrestrial body than any other American rover. On May 15, Opportunity set a record of 22.220 miles (35.760 kilometers) after finishing a 263-foot (80-meter) drive along the rim of Endeavour Crater. The previous record was set by United States astronauts Eugene Cernan and Harrison Schmitt in December 1972 on the moon. The two astronauts, members of the Apollo 17 mission to the moon, drove a lunar roving vehicle, also known as a moon buggy, 22.210 miles (35.744 kilometers) across the lunar surface. If Opportunity continues to exceed expectations—the rover was designed for only a 90-day mission—it will soon break the all-time off-world distance record of 23 miles (37 kilometers). That record was set on the moon in 1973 by the remote-controlled Lunokhod 2 rover launched by the Soviet Union (now Russia).

Opportunity (NASA/JPL-Caltech)

Opportunity and its twin, Spirit, were sent to Mars in 2003 as part of the Mars Exploration Rover Mission to study the history of water on the red planet. Their original 90-day mission turned out to be merely a warm-up. Both Spirit and Opportunity continued to gather information  without any major setbacks for more than five years. In early 2009, Spirit became permanently trapped in a bed of loose soil. NASA ended that rover’s mission in 2011. But Opportunity is still exploring.

Opportunity examines one of its major discoveries--the first meteorite found on a world other than Earth. (NASA/JPL-Caltech/Cornell University)

While traversing Mars, Opportunity found the first meteorite ever discovered on another world and rocky spheres created from water-bearing minerals. With Spirit, Opportunity also took the first photos of Earth-like clouds in the Martian sky from the planet’s surface and disovered convincing evidence that water once flowed across the Martian surface.

Additional World Book articles:

• Mars Pathfinder
• Mars Science Laboratory
• Space exploration
• The Search for Water on Mars (a special report)

January 8 2013

The NASA rover Curiosity, currently exploring the surface of Mars, has successfully used its brush tool for the first time. The tool’s rotating wire bristles are designed to sweep dust off the surface of rock. Brushing away dust gives Curiosity’s survey instrument–the arm-held hand lens camera and X-ray spectrometer–a clearer view of the texture and chemistry of the underlying rock–critical in selecting rock suitable for drilling.

The “dusting” is the final step toward the first deployment of Curiosity’s hammer-drill. The drill will produce a powdered sample that will be analyzed by the rover’s on-board laboratories. “We wanted to be sure we [have] an optimal target for the first use [of the dust removal tool],” stated Diana Trujillo of NASA’s Jet Propulsion Laboratory.

Curiosity’s Dust Removal Tool has cleaned a patch of rock in preparation for the rover’s first attempt to drill into the Martian surface. (NASA/JPL-Caltech/MSSS)

Curiosity, which landed on Mars in August 2012, is currently exploring an area known as Yellowknife Bay, a small depression in Gale Crater. The ultimate goal of the experiment is to determine whether microbial life might have flourished in Gale Crater in some past environments. Curiosity has already identified rock deposits laid down billions of years ago by running water, proof that other environments once existed in the crater.

Additional World Book articles:

• Mars Science Laboratory
• Microbiology
• Probing the Planets (a special report)
• The Search for Water on Mars (a special report)
• Space exploration 2003 (a Back in Time article)

August 6, 2012

The largest and most advanced robotic laboratory ever sent to another planet made a perfect landing on Mars early Monday morning after a descent so complicated and perilous that mission controllers referred to it as “the seven minutes of terror.” The automobile-sized rover, named Curiosity, touched down at 1:32 a.m. Eastern Daylight Savings Time, capping an 8 ½-month, 354-million-mile (570-million-kilometer) journey from Earth. Its mission is to answer one of the most important questions in planetary science–whether Mars is, or ever has been, capable of supporting microbial life. Mission controllers at NASA’s Jet Propulsion Laboratory erupted into cheers and high-fives as Curiosity set down in Gale Crater, an impact crater that may once have held a lake. Moments after landing, Curiosity beamed back its first photographs of the Martian surface.

One of the first images of Mars taken by Curiosity after landing. (Image credit: NASA/JPL-Caltech)

The rover’s nail-biting landing involved a rocket-powered sky crane, the world’s largest supersonic parachute, and the incredibly precise detonation of 79 explosive devices. A failure at any stage of the descent would have doomed the mission. Curiosity, officially named the Mars Science Laboratory, began its plunge through the Martian atmosphere seven minutes before landing. At an altitude of 7 miles (11 kilometers), the parachute deployed to slow the lab, which was traveling at 13,200 miles (21,243 kilometers) per hour. At precise moments, the heat shield then the parachute and part of the rover’s protective shell broke away, leaving only the rover and its sky crane, which fired its rockets. At about 65 feet (20 meters) above the surface, the crane began lowering the rover using three cables. Once Curiosity touched down, the cables broke away and the crane flew off to crash land away from the drop site.

The rover carries a scientific payload about 15 times as massive as those carried by NASA’s Mars rovers Spirit and Opportunity. Curiosity, which has been described as a self-contained geology laboratory, holds 10 sophisticated instruments, two of which were provided by Spain and Russia. Unlike earlier rovers, Curiosity will be able to gather samples of rock and soil, process them, and then distribute them to on-board instruments.

NASA's Curiosity rover is lowered onto the Martian surface by the sky crane, new technology designed specifically for this mission. (Image credit: NASA/JPL-Caltech)

Curiosity’s prime target is Mount Sharp (also known as Aeolis Mons), a mysterious 3-mile- (5-kilometer-) high mountain in Gale Crater consisting of layers of rock that may have been laid down over billions of years. Although the mountain looks similar to layered mountains on Earth, scientists do not know how it formed because, unlike Earth, Mars has not been shaped by plate tectonics. As the rover scales the mountain, it will analyze the layers in an attempt to discover how Mars, which was once warmer and wetter, became so cold and dry. It will also search for organic (carbon-bearing) molecules necessary for life as we know it. Curiosity is scheduled to explore the surface of the red planet for two Earth years (one Martian year). However, because it is powered by a nuclear generator, its mission may be extend for much longer.

Additional World Book articles:

• Mars Pathfinder
• Phoenix [spacecraft]
• Space exploration (Probes to Mars)
• The Search for Water on Mars (a Special Report)