NASA’s Perseverance rover has successfully isolated a leopard-spotted rock sample named Sapphire Canyon from an ancient river valley in Jezero Crater. The chalk-stick-sized sample exhibits potential microbial reduction spots, yet the Mars Sample Return program has been terminated due to unaffordable architecture options.
The Discovery of Sapphire Canyon at Jezero Crater
The Perseverance rover landed at the dried lakebed of Jezero Crater in February 2021 specifically to hunt for rocks modified by ancient water. In July 2024, the rover drilled the Sapphire Canyon sample from an arrowhead-shaped rock called Cheyava Falls. Surrounding mudstones were covered in hundreds of thousands of promising reduction spots potentially formed by ancient microscopic life.
Broz, coauthor of a study about the rock sample published in September 2025, noted the significance of the find. “When there’s organic matter that’s lodged in sediment or soil that’s buried and microbes start to digest some of that organic matter, they form these bleached halos and spots that are quite resemblant to the ones that Perseverance found in this ancient river valley,” Broz said. The sample is currently sitting in a tube on Mars.
Perseverance has collected 23 different rock samples from across the region. Using its onboard PIXL instrument, the rover detected fine-grained silica, iron associated with phosphate, and carbonate minerals in environments once rich in water, according to Ken Farley and Morgan Cable of the Perseverance science team.
The Termination of the Mars Sample Return Program
Returning the samples to Earth remains in limbo. The Mars Sample Return program faced intense scrutiny over a complex design and an estimated budget that ballooned to a maximum of $11 billion. NASA plans to terminate the Mars Sample Return Program given that current architecture options remain unaffordable.
NASA identified two strategies in January 2025 that relied on commercial partnerships or leaned on previously used Mars landing technology. No definitive timeline or replacement architecture has been revealed.
China’s Competing Tianwen-3 Mission Timeline
China is moving forward with plans to retrieve its own Martian samples. The Tianwen-3 mission is expected to launch in 2028. The mission design features a two-launch strategy utilizing an orbiter, a lander equipped with a 2-meter subsurface drill, an ascent vehicle, and a helicopter for sample collection.
Tianwen-3 chief scientist and economic geologist of the Chinese Academy of Sciences Zengqian Hou announced that engineers are building a prototype of Tianwen-3 while concurrently planning a planetary protection laboratory to house the samples.
