Self Portraits of Mars Rovers
A few days ago, NASA released this beautiful panoramic image of the Martian Landscape. While majestic by itself, the view is enhanced by the presence of the newest Mars Rover, Curiosity, in the middle of the picture, on top of the hill overlooking the whole planet. The photograph shows just how far NASA has reached in terms of being able to beam back images of robots on other planets, but this picture isn't the first self picture of a robot on Mars. These are some of the self-portraits of all Mars rovers to date.
To start with, the image above shows the Mars Pathfinder which landed on Mars in 1997. The mosaic is centered around the fixed lander called the Carl Sagan Memorial Station, and prominently shows the solar cells which powered the station. While technically not a rover, the Pathfinder package did contain a mobile robot named Sojourner which can be seen in the upper left-hand corner near Yogi Rock.
The Sojourner rover lasted only 83 sols (Earth days), but the Pathfinder mission was considered a success in that it was the first endeavor of its kind since NASA launched the Viking Program in 1976. Aside from the scientific findings of the planet's surface, the program proved that the airbag-method of landing was feasible. The small robot Sojourner also showed success in being able to maneuver on a foreign planet.
The above self photograph was taken by the rover Spirit (more formally known as Mars Exploration Rover - A) in 2007, midway through its life on Mars. The rover is one of two identical Mars rovers, the other being Opportunity. The rover was launched from Earth in 2003 and it arrived on Mars in early 2004.
The rover's panoramic camera shows the heavy dust build up on its solar panels, which greatly affected its ability to charge its batteries (this earlier self-portrait shows what the rover would look like with relatively clean panels). While strong winds would sometimes clean away the dust build up, this tendency to gather debris on itself would have a detrimental impact on the rover's life. The robot became stuck in soft soil in 2009, but continued to perform in a stationary position. Spirit sent its last communication in 2010, and NASA formally ceased communications attempts in 2011, after 2,208 successful working sols.
This last, shadowy portrait shows the still active Mars Exploration Rover B, also known as Opportunity, the twin brother of the Spirit rover. While the two robots landed on Mars at about the same time in 2004 (albeit in different locations), only Opportunity has continued to perform consistently, surpassing its original 90-sol mission. The rover celebrated it's 3,000 sol in the middle of last year, and it's still being used to explore the Meridiani Planum somewhere around Mars' equator.
On the other hand, the header photograph shows the youngest of the Martian rovers, Curiosity. This robot is about the size of a sedan, a mammoth compared to the earlier sojourner which was only the size of a milk crate. Curiosity's mission is to investigate the climate and geology of Mars, and help determine whether the planet's environment is conducive to microbial life.
For more information about these self portraits of all Mars rovers, check out the NASA's JPL Mars Exploration Rover homepage and mission page. For more photographs from beyond Earth, check out the Outer Space category of this blog.
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