Mars Exploration Rovers

Excavating the Future: What's the Job of the Mars Exploration Rovers?

Mars exploration rovers are automated vehicles that are sent to Mars, to study the various aspects of the planet. Unlike the orbiting spacecrafts, rovers can land on the Martian surface, propel around, and conduct microscopic examinations.
The planet Mars has always intrigued mankind with the possibility of the presence of aliens and other forms of life. Apart from this, various other reasons, like quest for water on Mars, prompted researchers to explore the Martian surface. Till date, almost 30 robotic spacecrafts with rovers, landers, and orbiters, have been sent to the planet.

As far as the rovers are concerned, a total of five were sent to Mars. The first two - Mars 2 Prop-M rover of 1971 and Mars 3 Prop-M rover of 1971, failed. The third one called Sojourner, sent with Mars Pathfinder spacecraft, landed successfully on July 4, 1997; but failed on September 27, 1997. This small rover weighing 25 pounds, was able to move just five meters from the lander.

Mars Exploration Rovers

The latest among the Mars rovers include the exploration rovers of NASA's 'Mars Exploration Rover Mission'. As a part of the mission, two rovers - Spirit and Opportunity, were sent to Mars on June 10, 2003 and July 7, 2003 respectively. While the rover 'Spirit' landed on January 4, 'Opportunity' landed on January 25, 2004. After completing five successful years, their mission was extended, and they are still exploring the Martian surface. The main aim of this mission is to study the water activity on the planet.

Spirit and Opportunity

The names of the rovers - Spirit and Opportunity, were chosen through a student essay competition won by a Russian-American third grade student, Sofi Collis. These two large Mars rovers were targeted to land on the opposite sides of the planet. Spirit landed at a site called Gusev Crater, which was formerly a lake. The landing site for Opportunity was Meridiani Planum, which is rich in mineral deposits. The spacecraft, protected by airbags (for cushioning purpose while landing), landed on the Martian surface, and opened up to roll out the rovers.

These solar-powered rovers are controlled by NASA's Jet Propulsion Laboratory. Both of them have six wheels, and weigh 185 kilograms. Each wheel has its own motor, and the maximum speed is two inches per second. Both the rovers are 1.5 meter high, 2.3 meter wide, and 1.6 meter long. Solar panels in the rover generate power, which is stored in its rechargeable lithium ion batteries. The rovers are fitted with a low gain antenna and a steerable high gain antenna for communicating with the laboratory on the Earth, and for sending the data collected.

The other equipment in Mars Exploration rovers are mainly used for exploration and examination of the Martian surface. Some of them are as follows:
  • A lower resolution, Monochromatic Navigation Camera, used for navigation and driving.
  • A Panoramic Camera, to determine the geological factors of the terrain.
  • A Miniature Thermal Emission Spectrometer to record the thermal readings and studies of the rocks and soil.
  • Four Monochromatic Hazard Cameras.
  • The rover arm is fitted with a Rock Abrasion Tool (RAT), to remove the dust and other particles from the rock surfaces, for examination by instruments on board. This tool can also drill rocks.
  • The rover arm also possesses a Microscopic Imager (MI) for obtaining close-up, high-resolution images of the rocks and soil.
  • An Alpha Particle X-Ray Spectrometer (APXS) is used by the rover arm to study the abundance of elements that make up the rock and soil of the planet.
  • Mössbauer spectrometer (MB) MIMOS II (also fitted in the rover arm), conducts examinations of the mineralogy of iron-bearing rocks and soil.
  • Magnets, in order to collect the iron-bearing sand particles on Mars for further study by Mössbauer Spectrometer and X-ray Spectrometer.
Extremely low night temperature on the planet can hinder the proper functioning of batteries and electronic components. To avoid this, the body of the rover is enclosed in a box called Warm Electronics Box, which provides suitable temperature settings. Scientists can select particular locations on the Martian surface, and the rover can move to such points for conducting investigations.

The two Mars Exploration rovers - Spirit and Opportunity, have survived the rough terrains and harsh Martian weather, thus helping us to discover many important facts about the planet. These rovers are still working, and we can hope for further discoveries about the planet Mars.