Curiosity is a NASA rover that has explored Gale Crater on Mars since August 6, 2012. Flown under the Mars Science Laboratory (MSL) mission and operated by the Jet Propulsion Laboratory (JPL), the car-sized, 899-kilogram rover was sent to answer a single overarching question: did Mars ever offer environmental conditions able to support microbial life.[1][2]
Within its first year Curiosity answered yes, finding evidence of an ancient freshwater lake with mild chemistry and the key elements needed by life. Since 2014 it has been climbing Mount Sharp, the 5.5-kilometer sedimentary mound at the crater's center, reading layers that record Mars's transition from a wet climate to a dry one. Along the way it has detected organic molecules of increasing size and complexity, measured seasonal methane in the atmosphere, and, in 2025, surveyed a striking network of mineral ridges called boxwork formations.[2][3]
The rover remains active nearly 14 years after landing, far beyond its two-year prime mission. As of July 1, 2026, it had driven 36.86 kilometers across 4,942 Martian days, or sols.[1]
The sky-crane landing
Curiosity launched on November 26, 2011, on an Atlas V 541 from Cape Canaveral. At five times the mass of earlier Mars rovers, it was too heavy for airbag landings, so JPL devised a new sequence: a guided atmospheric entry, the largest supersonic parachute then flown, and a rocket-powered descent stage that hovered while lowering the rover on nylon tethers, then flew away to crash at a safe distance. Engineers called the seven-minute automated sequence the "seven minutes of terror".[2]
The sky crane worked on its first try. Curiosity touched down at 05:17 UTC on August 6, 2012 (the evening of August 5 in California), about 2.4 kilometers from the center of its target ellipse, at a spot named Bradbury Landing. The same landing architecture was reused in 2021 for the Perseverance rover.[1][2]
Ascent of Mount Sharp
Gale is a 154-kilometer impact crater whose central mound, formally Aeolis Mons, preserves kilometers of stacked sediments. Mission strategy has been to climb the mound and examine each successive layer, moving forward in geological time.
| Period | Location | Significance |
|---|---|---|
| 2012-2013 | Bradbury Landing and Yellowknife Bay | Ancient streambed gravels; first drill samples |
| 2014 | Pahrump Hills | Arrival at the base of Mount Sharp |
| 2017-2019 | Vera Rubin Ridge | Hematite-bearing ridge |
| 2019-2021 | Glen Torridon | Clay-rich trough recording lake deposits |
| 2022-2024 | Sulfate-bearing unit and Gediz Vallis | Salty minerals from a drying climate; stones of pure sulfur |
| 2025-2026 | Boxwork formations and beyond | Ridge networks left by late groundwater |
By January 2025 the climb had raised the rover's elevation more than 740 meters above its landing site, and it continues upward through the sulfate-bearing layers.[1][2]
Key science findings
Curiosity's first drill campaign at Yellowknife Bay in February 2013 recovered mudstone laid down in a calm freshwater lake. The rock contained clay minerals, a neutral-pH chemical environment, and the biologically essential elements carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. NASA concluded that ancient Gale Crater could have supported living microbes, satisfying the mission's primary goal within eight months.[2]
The rover's SAM laboratory has steadily expanded the inventory of Martian organic chemistry. In 2018 the team reported three-billion-year-old organic matter preserved in lakebed mudstones. In March 2025, a reanalysis of the Cumberland sample drilled back in 2013 revealed decane, undecane, and dodecane, chains of 10 to 12 carbon atoms and the largest organic molecules yet found on Mars. The authors suggest they may be fragments of long-chain carboxylic acids; whether the source chemistry was biological or abiotic cannot be determined from rover data alone.[4][5]
Atmospheric measurements found methane at a faint background level near 0.4 parts per billion that rises and falls with the seasons, punctuated by transient spikes, including one of about 21 parts per billion in June 2019. The gas's origin, geochemical or biological, remains unresolved. Curiosity has also logged the surface radiation environment for future crewed missions and, in 2024, cracked open a rock in the Gediz Vallis channel to reveal crystals of elemental sulfur, a find the team had not anticipated.[1][2]
Boxwork formations
In mid-2025 Curiosity reached a long-planned target: a stretch of low ridges arranged in polygons that resemble giant spiderwebs in orbital images, spanning kilometers of lower Mount Sharp. These boxwork formations formed billions of years ago when mineral-laden groundwater seeped through fractures in the rock; the minerals hardened in the cracks, and wind later stripped away the softer surrounding stone, leaving the cemented lattice standing in relief. Because they record some of the last widespread liquid water in the region, they offer a way to study how long habitable conditions persisted as Mars dried out.[3][6]
The rover photographed the terrain extensively, including a panorama on September 26, 2025 (sol 4,671) and a 360-degree mosaic assembled from 1,031 images taken between November 9 and December 7, 2025. It examined targets at two sites chosen to capture the wet-to-dry transition before finishing the survey and driving on across the sulfate-bearing unit in early 2026.[3][6]
Status in 2026
Curiosity marked 13 years on Mars in August 2025, and its operators used the anniversary to describe a set of new capabilities: the rover can now combine tasks, such as communicating while driving, and can end activities early and nap when a plan finishes ahead of schedule, conserving the slowly declining output of its radioisotope generator.[7]
Wheel damage, first noticed in 2013, is managed through route selection and a traction-control algorithm added in 2017, and the wheels have already carried the rover several times farther than their original design requirement.[8] As of July 1, 2026, the odometer stood at 36.86 kilometers.[1] The mission has no fixed end date; the team plans to keep climbing through the sulfate layers, using the boxwork results and new drill samples to chart when, and how quickly, ancient Mars lost its water.[2][7]
References
- Curiosity (rover) - Wikipedia.
- Mars Science Laboratory: Curiosity Rover - NASA Science.
- NASA's Perseverance, Curiosity Panoramas Capture Two Sides of Mars - NASA Jet Propulsion Laboratory.
- Long-chain alkanes preserved in a Martian mudstone - Proceedings of the National Academy of Sciences.
- Curiosity rover detects long-chain carbon molecules on Mars - Science.
- Image: Curiosity rover surveys boxwork region of Mars - Phys.org.
- Marking 13 Years on Mars, NASA's Curiosity Picks Up New Skills - NASA.
- 10 Years Since Landing, NASA's Curiosity Mars Rover Still Has Drive - NASA.
