Curiosity is the most popular but Opportunity managed to provide a high amount of information about the Red Planet.
The rover lost contact with Earth back in June in 2018 when a massive dust storm surrounded the planet completely. Unlike Curiosity which employs a nuclear power core Opportunity relied on solar panels in order to gather the required energy. The thick clouds of dust blocked out the sunrays, leaving the rover on a limited energy reserve. When the reserve was almost depleted the rover entered a hibernation mode in order to conserve the remaining power.
The storm lasted until August when the skies started to become clear again. The agency tried to contact the rover as soon as the weather improved but all the attempts resulted in failure. In the last months a technique called sweep and beep was used in order to attempt to contact the rover. Instead of waiting for the rover to answer NASA is constantly sending a beep command to the rover. No answer has been received until now.
The researchers are now contemplating three scenarios that could prevent the rover from answering. In the first case the primary X-band radio has been compromised by the savage winds that whipped the planet as the storm was in progress. The second scenario takes into account the possibility that the backup radio was also affected by the extreme weather and rendered unusable. A third and last scenario suggests that the internal clock may have been influenced by the lack of solar energy. NASA is attempting to trigger the radios and to reset the watch in order to see if the scenarios are viable.
As the days pass the possibility of successfully contacting the rover continue to decrease. NASA has decided that this will be the last attempt as the winter season is beginning on Mars. The low temperatures that are set to come are likely to cause permanent damage to the rover’s systems.
The attempts to contact the rover will continue for a few weeks.