What just happened? NASA is on track to bring Mars core rock samples back to Earth by the middle of the next decade as part of its Mars sample-return (MSR) mission. A recent system requirements review prompted the space agency to modify its original plan to reduce the mission's complexity and increase the probability of success.

Thomas Zurbuchen, associate administrator for science at NASA, said Perseverance's successes in the Red Planet's Jezero Crater and the performance of the Mars helicopter played a key role in their decision to modify the mission.

Perseverance and its accompanying helicopter, Ingenuity, landed on Mars on February 18, 2021, and both have exceeded expectations. Perseverance has already collected nearly a dozen scientifically-compelling rock samples and one atmospheric sample. Ingenuity was expected to fly just five times within a 30-Martian-day demonstration window but has made 29 successful flights as of June 11, 2022.

As such, the MSR campaign will no longer include a Sample Fetch Rover and its associated second later. Instead, the Sample Retrieval Lander will be equipped with two sample recovery helicopters based on Ingenuity. NASA said the choppers will provide a secondary means to retrieve samples cached on the surface of the Red Planet.

Previously planned components including the Capture, Containment and Return System as well as the Earth Return Orbiter will remain unchanged from the original plans.

Having completed the conceptual design phase, the project will enter the preliminary design phase in October. During this year-long period, engineers will complete technology development and craft prototypes of the mission's major components.

NASA is working with the European Space Agency on the project.

"ESA is continuing at full speed the development of both the Earth Return Orbiter that will make the historic round-trip from Earth to Mars and back again; and the Sample Transfer Arm that will robotically place the sample tubes aboard the Orbiting Sample Container before its launch from the surface of the Red Planet," said David Parker, ESA director of Human and Robotic Exploration.

The two expect to launch the Earth Return Orbiter in the fall of 2027 followed by the Sample Retrieval Lander in the summer of 2028. Should everything go according to plan, the payload will arrive back on Earth in 2033 and allow scientists from around the world to study them using instruments that are too large and complex to send to Mars.