Mars Exploration Rover

The planet Mars has always intrigued mankind with the possibility of the presence of aliens and the 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 including rovers, landers and orbiters have been sent to the planet.

Mars Rovers

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

Mars Exploration Rovers

The latest among Mars rovers include the exploration rovers, which are a part of the NASA's 'Mars Exploration Rover Mission'. As a part of the mission, two rovers - Spirit and Opportunity, were sent to Mars on June 10 and July 7, 2003 and landed on January 4 and January 25, 2004, respectively. After completing five successful years, their mission was extended, and they are still working. One of the main aims 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 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. They have six wheels and weigh 180 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 and store it 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 earth, thereby sending the data collected.

The other equipment in rovers are mainly used for the exploration and examination of the Martian surface. Some of them are as follows:

• A lower resolution, monochromatic navigation camera, used for navigation and driving.
• 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 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 stop the 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 that point for conducting investigations.

The two Mars 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.