The Curiosity Rover: Mission, Predecessors, Specifications, and Achievements
Mars, the Red planet. The fourth planet from the sun, named for the Roman God of War, distinguishable at a distance by its distinct red color. And yet infinitely more thought provoking up close. Scanning its surface, one sees a barren wasteland of red soil, with a thin atmosphere of Carbon Dioxide and a spattering of volcanoes, a cold and lifeless planet. However, we see evidence that it was not always so. At its poles we see ice caps highlighted against the planet's red surface, a surface that is not barren, but crisscrossed with massive canyons and valleys that almost look like river deltas. Could these be the remnants of ancient river beds that flowed with water in the worlds ancient past? And could those rivers have possibly supported life? These questions have baffled scientists for generations, and now with the power of robotics, we are finally starting to answer some of these important cosmic questions.
The Robotic Exploration of Mars
The earliest missions to Mars, both from the US and USSR, had a tendency to fail spectacularly. The first successful mission was Mariner 4. The first lander to return any data was Mars 3, which relayed 20 sec. of video from the red planet. However, true success didn't come until the launch of Viking 1 & Viking 2 in 1975. Each of these stationary landers provided extensive photographic information and data on soil and atmospheric composition. They would later be followed by the Mars Global Surveyor, an orbiter responsible for pictures such as the one above. But even this would not be the end
In 1996, the Mars Pathfinder project launched, deploying the Sojourner Rover. Though this rover did little science of its own, it served as a proof of concept that would has proved crucial since. In particular, Sojourner was the progenitor of the later twin rovers Spirit and Opportunity, launched in 2003. These two remarkable rovers where expected to last a mere 90 days, and have happily surprised us all as Spirit survived into 2010, and Opportunity is even now roving the surface of mars. Each of these rovers have exponentially increased our knowledge of the red planet, and provided strong evidence for there having once been a watery mars, not unlike our Earth. However, even the remarkable Spirit and Opportunity pale in comparison in terms of scientific potential to the latest robot to patrol the Martian surface, the Mars Science Laboratory, Curiosity.
The earliest missions to Mars, both from the US and USSR, had a tendency to fail spectacularly. The first successful mission was Mariner 4. The first lander to return any data was Mars 3, which relayed 20 sec. of video from the red planet. However, true success didn't come until the launch of Viking 1 & Viking 2 in 1975. Each of these stationary landers provided extensive photographic information and data on soil and atmospheric composition. They would later be followed by the Mars Global Surveyor, an orbiter responsible for pictures such as the one above. But even this would not be the end
In 1996, the Mars Pathfinder project launched, deploying the Sojourner Rover. Though this rover did little science of its own, it served as a proof of concept that would has proved crucial since. In particular, Sojourner was the progenitor of the later twin rovers Spirit and Opportunity, launched in 2003. These two remarkable rovers where expected to last a mere 90 days, and have happily surprised us all as Spirit survived into 2010, and Opportunity is even now roving the surface of mars. Each of these rovers have exponentially increased our knowledge of the red planet, and provided strong evidence for there having once been a watery mars, not unlike our Earth. However, even the remarkable Spirit and Opportunity pale in comparison in terms of scientific potential to the latest robot to patrol the Martian surface, the Mars Science Laboratory, Curiosity.
Technical Stats of Curiosity
Curiosity was built by NASA (National Aeronautics and Space Administration) at JPL in conjunction with private corporations Boeing and Lockheed Martin, at an estimated cost of $2.5 billion (compare to $156.5 billion for Apollo, or $1.38 trillion on the wars in Iraq and Afghanistan).
The Mars Science Laboratory is exactly what it says and so much more. Curiosity was built to be a completely self contained mobile laboratory. Here are some statistics on it:
Curiosity was built by NASA (National Aeronautics and Space Administration) at JPL in conjunction with private corporations Boeing and Lockheed Martin, at an estimated cost of $2.5 billion (compare to $156.5 billion for Apollo, or $1.38 trillion on the wars in Iraq and Afghanistan).
The Mars Science Laboratory is exactly what it says and so much more. Curiosity was built to be a completely self contained mobile laboratory. Here are some statistics on it:
- The Rover is 10 ft. long, 9 ft. wide, and 7 ft. tall and weighs 1,982 lb.; it also has a top speed of .09 mph
- It has an onboard plutonium based Radioisotope Thermoelectric Generator, which derives energy from the decay of radioactive isotopes, and two rechargeable lithium-ion batteries for power storage.
- Curiosity has titanium wheel struts and 20 in. aluminum wheels with traction "cleats." In addition to the main camera on the robot's "head," it also has a number of Hazard Avoidance Cameras on either side of it.
- Curiosity's head includes 2 sets of "NavCams" for navigation, a broad field camera for a left "eye" and a high focus camera at the right, able to distinguish between a basketball and a football at 700 ft. It also carries the "ChemCam," which uses a laser to vaporize a small piece of rock and then analyzes the spectra of the resultant gas so that scientists on earth can decide if it is worth further investigation.
- The Rover has 3 radio antennae for communicating with earth, a high-gain antennae for receiving and requesting directions, a low gain for transmitting low volume data streams, and finally a "short" range UHF antennae for transmission with the orbiter to transfer large data streams.
- The Science equipment on the body of the robot include sensors for detecting organic molecules in martian solid, measuring ambient radiation, and identifying minerals that were likely formed in water, and a Russian-built sensor for detecting hydrogen, a possible remnant of past water, as well as a portable weather station on the "neck."
- Curiosity's Robotic Arm is 7ft long with 5 degrees of freedom, and ends in a "hand" which includes a spectrometer for chemical analysis, a high-focus camera, a drill, a dust brush, and a sifting tool for preparing samples. Extra drill bits are stored on the rover.
Martian Landing
Landing on Mars is no easy task. Heck, even getting there is a challenge in and of itself, based on the sheer number of mission failures that have occurred. But there are 3 landing methods that stand out as successful techniques. Here they are, in chronological order:
Landing on Mars is no easy task. Heck, even getting there is a challenge in and of itself, based on the sheer number of mission failures that have occurred. But there are 3 landing methods that stand out as successful techniques. Here they are, in chronological order:
- For a lander, the lander is carried within a capsule with a heat shield and parachute, which carries it through most of the atmosphere. Then, once a certain altitude and alignment is reached, the lander is released from the capsule, and then uses retro-rockets to slow its decent into a smooth landing. This technique was used first in Vikings 1 and 2, and has been used in the Phoenix Lander and the unsuccessful Beagle 2.
- For Small Rovers a more complex system is used. The Capsule uses its heat shield to enter the atmosphere first, then slows itself down using parachutes and retrorockets. Once a certain speed is reached, the lander is lowered in a smaller container on a tether. Airbags surround the smaller container inflate, and at around 30m the tether is released, allowing the lander to fall and bounce on its airbags until it stops, at which point the rover can simply unfold itself and drive off. This technique was first tested with Pathfinder's Sojourner rover, and put into practice with Spirit and Opportunity.
An incomplete list of Curiosity's Discoveries
Curiosity has provided a wealth of new scientific data and proven several important concepts during its short time on the red planet. Here are a few examples:
Curiosity has provided a wealth of new scientific data and proven several important concepts during its short time on the red planet. Here are a few examples:
- Radiation levels on Mars are within tolerable limits for a potential extended manned mission, without excess risk of long term side effects.
- Locating an ancient stream-bed with evidence of the presence of water in the past.
- Found crucial elements for life (Carbon, Oxygen, Hydrogen, Nitrogen, Phosphorus, and Sulfur) in martian rock, alongside evidence of the presence of water in the distant past, providing evidence for a once-habitable Mars.
Sources:
- "Curiosity Mars Science Laboratory." NASA. NASA, n.d. Web. 29 Sept. 2014.
- NOVA Mars: Dead or Alive. WGBH Boston, 2004. TV Documentary.
- NOVA Welcome to Mars. WGBH Boston, 2005. TV Documentary.
- "The Cost of Curiosity." Amy Shira Teitel. N.p., n.d. Web. 29 Sept. 2014.
- "Mars Rover Curiosity's 7 Biggest Discoveries (So Far)." Space.com. N.p., n.d. Web. 29 Sept. 2014. <http://www.space.com/20396-mars-rover-curiosity-big-discoveries.html>
- "Mars Science Laboratory." Mars Science Laboratory. N.p., n.d. Web. 29 Sept. 2014. <http://mars.jpl.nasa.gov/msl/>.