The moon has been visited plenty of times by state-owned space programs, but it’s about to have some company from the private sector. The Google Lunar X Prize—an international competition to send a private craft to the moon— has its five finalists, all of whom will try to reach the moon’s surface by the end of the year.

The last five standing from the initial field of 16 include SpaceIL of Israel, Moon Express representing the U.S., TeamIndus from India, Japan’s Hakuto and an international team with representatives from more than 15 countries called Synergy Moon.

The teams still active in the Google Lunar X Prize, which first launched in 2007, were able to successfully secure a rocket to launch their craft into space and provide a contract proving their craft would have a ride.

While one would imagine getting to the moon is the hardest part, the contract led to enough hang ups that the contest deadline was extended by a full year so teams could ensure they would have access to a rocket.

SpaceIL was the first to ink a deal. Its craft, the Sparrow, will be hitching a ride on one of SpaceX’s Falcon 9 rockets during the second half of 2017. The California-based Moon Express, which secured U.S. government approval for its mission, tapped aerospace startup Rocket Lab and their small, experimental Electron rocket—one that has yet to ever be launched—to get it to space.

Synergy Moon’s lunar lander will be riding atop Interorbital Systems’ Neptune 8 rocket, which like the Electron has yet to fly. TeamIndus and Hatuko will be sharing a flight on the PSLV rocket launched by the Indian Space Research Organization.

A sixth team—the Part Time Scientists of Germany—were close to making the deadline for the final leg of the competition, announcing a contract with Spaceflight Industries in late November 2016. The contract couldn’t be verified by the contest operators, and the Part Time Scientists were left behind.

The last challenge for the five teams remaining will be landing on the moon. Once there, the rovers they send up will have to successfully travel 500 meters on the lunar surface. The rovers will also have to send back photos and provide a live video feed.

Teams have until Dec. 31, 2017 to finish the remaining tasks. The first team to complete the mission will score a $20 million grand prize. Second place will walk away with $5 million, and bonuses will be given to teams that complete specific tasks like visiting the Apollo landing site.