How NASA will bring a little bit of Mars back to Earth

When NASA’s Mars 2020 rover blasts off this summer, it will mark the first step of an ambitious plan to bring pieces of the red planet back to Earth.

The new rover will collect samples of Martian rock and soil that will later be retrieved and launched into space so they can begin their interplanetary journey.

These samples will be a game changer in understanding our next-door neighbor, scientists say. NASA rovers have already found that Mars once had water and the right chemical ingredients to be friendly to life. But figuring out whether life ever actually existed there is a much trickier question — one that can only be answered by subjecting pieces of the red planet to cutting-edge instruments on Earth.

If successful, the joint effort between NASA and the European Space Agency will be humanity’s first round-trip visit to another planet. Here’s how it will work:

After landing in Jezero Crater in 2021, the Mars 2020 rover will gather samples of Martian soil and rock.

The rover will store those samples in sealed metal tubes and leave them on the ground.

In 2028, a NASA lander will touch down nearby. It will carry a small rover built by the European Space Agency to fetch the cylinders, as well as a NASA rocket to send them into orbit.

The lander will deploy its solar panels and begin operations on the surface.

ESA’s Sample Fetch Rover, comparable in size to NASA’s Spirit and Opportunity rovers, will collect the sample tubes and bring them to the lander.

The lander’s robotic arm will then take the tubes from the fetch rover and load them into a basketball-sized vessel in the nose of the rocket. There’s also an option for Mars 2020 to make sample deliveries.

The NASA-built vessel will keep its precious contents at a temperature below 86 degrees Fahrenheit to preserve them close to their natural state.

Once loaded, the rocket will blast off, becoming the first to launch off another planet.

After the rocket reaches space, it will release the spherical sample container into orbit.

An ESA spacecraft outfitted with a NASA-built processing system will collect the orbiting sample container while they both circle the red planet.

That spacecraft, ESA’s Earth Return Orbiter, will then ferry the samples back to scientists.

Once it arrives around 2031, the spacecraft will release a NASA entry capsule containing the sample container for the final plunge toward Earth.