Curiosity (rover) arm operations were cleared to continue, but drilling remained suspended indefinitely. The "Curiosity" team continued to perform diagnostics and testing on the drill mechanism throughout 2017. "Curiosity" has an advanced payload of scientific equipment on Mars. It is the fourth NASA unmanned surface rover sent to Mars since 1996. Previous successful Mars rovers are "Sojourner" from the Mars Pathfinder mission (1997), and "Spirit" (2004–2010) and "Opportunity" (2004–present) rovers from the Mars Exploration Rover mission. "Curiosity" is long by wide by in height, larger than Mars Exploration Rovers, which are long and have a mass of including of scientific instruments. In
Timeline of Mars Science Laboratory atmosphere. This creates wind, which in turn stirs up more dust. This results in a feedback loop that scientists are still trying to understand. NASA reported on June 20, 2018 that the dust storm had grown to completely cover the entire planet. On June 4, 2018, NASA announced that "Curiosity" ability to drill has been sufficiently restored by engineers. The rover had experienced drill mechanical problems since December 2016. On June 7, 2018, NASA announced a cyclical seasonal variation in atmospheric methane, as well as the presence of kerogen and other complex organic compounds. The organic compounds were from mudstone