WASHINGTON, May 31 (Xinhua) -- The United States space agency NASA on Friday unveiled three lunar landers that will carry NASA science payloads to the Moon and pave the way for NASA astronauts to land on the lunar surface by 2024.

The three robotic landers are developed by American Moon landing service providers -- Astrobotic Technology, Intuitive Machines and Orbit Beyond -- under Commercial Lunar Payload Services program, according to NASA.

Astrobotic Technology, a Pittsburgh-based company, proposed to fly a total of 14 payloads to Lacus Mortis, a large crater on the near side of the Moon, by July 2021.

Intuitive Machines, a Houston-based company, proposed to fly five payloads to Oceanus Procellarum, a dark spot on the Moon, by July 2021.

Orbit Beyond, a company in New Jersey, proposed to fly four payloads to Mare Imbrium, a lava plain in one of the Moon's craters, by September 2020.

NASA will determine which payloads will fly on each flight by the end of the summer, according to NASA.

This first batch are among nine American companies selected in November 2018 in a competition to build lunar robotic landers for NASA in the coming decade.

"These landers are just the beginning of exciting commercial partnerships that will bring us closer to solving the many scientific mysteries of our Moon, our solar system, and beyond," said Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate, in a statement.

NASA also selected 11 private companies on May 16 to conduct studies and produce prototypes of human landers for putting American astronauts including the first woman on the Moon's south pole by 2024.