April 8, 2019

After nearly 15 years on the surface of Mars, the Opportunity rover died as it lived: studying its adopted home planet. The United States National Aeronautics and Space Administration (NASA) officially ended the rover’s mission in February 2019, months after the craft was silenced by a dust storm.

The NASA Mars rover Opportunity studied the red planet from January 2004 until the summer of 2018. Credit: NASA/JPL/Cornell University, Maas Digital LLC

Opportunity and its twin vehicle, Spirit, together made up the Mars Exploration Rover Mission. They were launched in 2003 to study the history of water on the red planet. The golf-cart-sized rovers carried scientific instruments created by teams of scientists and engineers from the United States and Europe.

Spirit and Opportunity were each designed for just 90-day missions. But both continued to gather information on the surface of Mars without any major setbacks for more than five years. In early 2009, Spirit became permanently trapped in a bed of loose Martian soil, ending that rover’s exploring career. Finally accepting its loss, NASA officially ended Spirit’s mission in 2011.

Opportunity landed in January 2004 in Meridiani Planum, a broad plain on the surface of Mars. Planners chose the site because it was known to contain hematite. Hematite is an iron-bearing mineral. On Earth, hematite generally forms in the presence of water. In 2013, Opportunity detected certain clay minerals that form only in the presence of water. This discovery was proof that liquid water once existed on the surface of Mars. This finding was confirmed by other Mars missions, such as NASA’s larger Curiosity rover, sent to Mars in 2011. Opportunity went on to learn that the water was similar to bodies of water on Earth, allowing for the possibility of life on Mars.

Huge dust storms occasionally blanket the surface of Mars. A particularly intense storm occurred in mid-2018, causing NASA to lose contact with Opportunity. The dust blocked out the sun and covered the rover’s solar panels, making it impossible for Opportunity to keep its core systems warm. Even after the skies cleared, there was no response from the rover. The bitterly cold temperatures on Mars—about -80 °F (-60 °C) on average—can damage and destroy electronics.

The end of Opportunity is not the end of humankind’s robotic presence on Mars. Curiosity continues to roll along. InSight, a non-mobile lander also launched by NASA, is currently studying the interior structure of Mars. And in 2021, two new rovers will launch: NASA’s Mars 2020 rover and Rosalind Franklin, a rover developed by the European Space Agency (ESA) and Russia’s state space agency, Roscosmos. (Rosalind Franklin was a British chemist famous for her studies of molecules and crystals.) The new rovers will try to find out if Mars held life at some point in its distant past. Thanks to the hard work of Opportunity and the mission’s engineers and scientists, we know it is a possibility.

March 27, 2015

This week, the rover Opportunity reached 26.2 total miles of travel on Mars, the Martian equivalent of an earthling marathon. The rover’s 0.00027-mile-per-hour average pace would not set any records on this planet, but Opportunity holds the record for the first (and only) marathon completed off Earth. Eleven years and two months is the time to beat.

NASA’s Opportunity rover appears in this computer-generated image. Credit: JPL/NASA

Opportunity is one of two identical probes sent to Mars in 2003 as part of the Mars Exploration Rover Mission to study the history of water on the planet. Engineers and scientists at the Jet Propulsion Laboratory designed and built the rovers for the United States National Aeronautics and Space Administration (NASA). Opportunity carries instruments created by teams of scientists and engineers from across the United States and Europe. The two rovers have helped scientists learn that water existed on the surface of Mars billions of years ago and that this water might have provided a suitable habitat for life.

Opportunity has traveled farther than any other off-Earth ground vehicle, including the piloted lunar rovers used in some of the Apollo missions. In July 2014, Opportunity broke the previous off-Earth record of 24.2 miles set in 1973 by the Soviet lunar rover Lunokhod 2.

Opportunity’s marathon shows just how tough and long-lived the little rover is. Opportunity and its twin Spirit were originally designed for 90-day missions. But they both continued to gather information on the surface of Mars long after that. Opportunity has powered through rugged terrain and age-related equipment problems to gather important information about the history of water on the Red Planet. This year, scientists worked to bypass a memory problem that caused the rover to “forget” the data it collected before sending it back to Earth.

Other World Book articles:

• Mars Pathfinder
• Mars Science Laboratory
• Astronomy (2004) (a Back in Time article)
• The Search for Water on Mars (a Special Report)