NASA has picked Jezero Crater as the landing spot for its upcoming Mars 2020 rover mission, after scrutinizing more than 60 potential locations over the last five years.

The mission: The rover, set to launch in July 2020, will look for signs of ancient habitable conditions and past microbial life, collecting rock and soil samples for storage on Mars’s surface. NASA and the European Space Agency plan to eventually retrieve these samples and bring them back to Earth. “This landing site sets the stage for the next decade of Mars exploration,” NASA said.

Why Jezero Crater? The 28-mile-wide crater, which used to be the site of a river delta, is in an area that includes some of Mars’s oldest and most scientifically significant landscapes. Scientists believe ancient organic modules could have collected and been preserved from the water and sediments that flowed into the crater as far back as 3.6 billion years ago. There are at least five different types of rock present and potentially a wide variety of minerals.

The technology: The geologic diversity that makes Jezero such an appealing landing site also makes landing there a huge technical challenge for engineers. However, NASA has been working on a range of new technologies to improve entry, descent, and landing. One is Terrain-Relative Navigation, which can accurately work out where the rover is headed and divert to a safer place if it looks like a tricky surface.