Mars has intrigued people for centuries, in particular because of its potential for extraterrestrial life. Today, technology has advanced to the point that scientists can actually send robots such as those used in NASA's Mars Exploration Rover (MER) mission to study Mars. In this video segment from NOVA, learn about the MER mission and why scientists are so interested in exploring the red planet.
Compared to Earth, Mars has an incredibly harsh environment. Four decades of Mars exploration, which began in 1960, have demonstrated that the planet is an inhospitable, frigidly cold, arid place. Its surface is littered with craters and giant volcanoes and abused by planet-wide dust storms. Mars' atmosphere is so thin that the pressure is less than 1% of the atmospheric pressure at Earth's surface. The thin atmosphere on Mars contains virtually no oxygen, a requirement of life for almost all organisms on Earth, and offers no protection from incoming ultraviolet solar radiation. The planet experiences extreme fluctuations in temperature from day to night, and the average surface temperature is a frosty -63°C (-81°F). At these temperatures, water cannot exist in its liquid form, and all life, at least as we know it, requires liquid water.
Yet, Mars remains an alluring planet to explore for signs of extraterrestrial life. Despite the lack of liquid surface water, ice exists in the planet's polar ice caps and water vapor is present in the atmosphere. There is also evidence of subsurface water. More importantly, liquid surface water may have been present in the past. Previous missions to Mars have found indicators of water, such as channels that could have been carved by flowing water and characteristic erosion features in craters. This means Mars may have once been warm enough to have liquid water. Many scientists are convinced that where they can find water, there is a chance they may find life.
In 2003, the Mars Exploration Rover mission was launched with the goal of learning more about the geological history of the planet, particularly the role that liquid water may have played. To carry out this task, two robotic geologists were sent to explore the planet. The rovers, controlled by team members on Earth, had to weather the hostile environment to carry out their missions. Even for a robot, the extreme temperature changes and dusty conditions, along with the rocky and hazardous terrain, posed challenges. Nevertheless, Spirit and Opportunity landed in January 2004 and successfully completed their three-month-long primary missions. They delivered to scientists conclusive evidence that liquid water once existed on the surface of Mars. As of August 2005, the rovers were still operating, continuing their active exploration of the planet.
Investigate the variables that affect a parachute's rate of descent in this NOVA classroom activity.
Academic standards correlations on Teachers' Domain use the Achievement Standards Network (ASN) database of state and national standards, provided to NSDL projects courtesy of JES & Co.
We assign reference terms to each statement within a standards document and to each media resource, and correlations are based upon matches of these terms for a given grade band. If a particular standards document of interest to you is not displayed yet, it most likely has not yet been processed by ASN or by Teachers' Domain. We will be adding social studies and arts correlations over the coming year, and also will be increasing the specificity of alignment.