NASA has chosen the first companies that will ferry its instruments to the moon as part of the Artemis program — and with those selections come hints about where the contracted landers will touch down.
On May 31, NASA announced that it was hiring Astrobotic, Intuitive Machines and Orbit Beyond to carry its first modern set of science experiments and technology demonstrations to the moon. The payloads represent the first segment of the agency's ambitious Artemis program, its plan to land humans at the moon's south pole in 2024. But none of these three landers are destined for that region.
"We'll have more selections of course; part of the reason for that is there's a number of locations we want to go to; we'll have a maximum of three here," Thomas Zurbuchen, head of NASA's science mission directorate, said on May 31 during a live event announcing the three selections. "In every case actually part of the proposal that was submitted had a location identified. We will now work with the companies and actually look at options just to make sure we maximize the system."
Related: NASA Unveils New Detailed Photos of Apollo Moon Landing Sites
This map of the northern hemisphere of the near side of the moon shows the areas that NASA's first three commercial lander missions are targeting.
All three companies are targeting sites in the northern hemisphere of the near side of the moon, and all the companies are targeting smooth lava flows that filled in existing craters long ago. That's a safety measure: The flatter the land, the more likely a spacecraft can touch down without becoming unbalanced by hitting a rock.
"We selected a nice smooth flat plain mainly because landing is the most important thing on the first mission, to prove that we can do that," Sharad Bhaskaran, Astrobotic mission director, said during the May 31 event.
More specifically, Astrobotic has selected Lacus Mortis, in part because of scientific interest in a nearby pit, Bhaskaran said. That said, the company does not intend to be limited to that site in the future.
"In the future our spacecraft can go to any location on the moon with minor changes to the spacecraft," he said. "We can go to craters, pits, equatorial, polar regions, and we're excited about those future missions to do all of those interesting things in science."
Just how much information has been released about the landing sites varies from company to company. During the media event, Orbit Beyond's chief science officer, Jon Morse, said simply that the company was targeting a 2-kilometer landing ellipse near Mare Imbrium. "These are the vast lava plains of the Sea of Rains," he said. Later, company tweets said that the lander would aim to touch down near the small Annegrit crater, the ridge of Dorsum Zirkel and a mountain called Mons La Hire.
The third company to take on the challenge of ferrying NASA's lunar payloads is earlier in the site-selection process. Intuitive Machines is still deciding between candidate sites at Oceanus Procellarum and at Mare Serenitatis, Tim Crain, the company's vice president for research and design, said during the media event.
For Intuitive Machines, another crucial criterion to consider in site selection is timing. "Since we're solar powered, we target most of our landings to be in the lunar morning so we'll have the maximum amount of solar power for the lander," Crain said. (On the moon, days and nights each last for about the equivalent of 14 Earth days, so there's plenty of time to work between dawn and dusk.)
Unsurprisingly, all four of these sites are located on the near side of the moon. Only one mission, China's Chang'e 4 lander and rover, has touched down on the far side of the moon. The feat is complicated by the moon's tidal lock with Earth, which leaves spacecraft on the far side unable to communicate directly with humans; such missions require a communications relay satellite in orbit around the moon.
Artists' depictions of lunar lander designs from commercial companies Astrobotic, Intuitive Machines and Orbit Beyond. NASA selected the trio of companies to ferry their first science and technology payloads to the moon's surface as part of the Artemis program, the agency's plan to land humans on the moon in 2024.
These targeted landing sites also steer clear of some of the most talked-about lunar features, stashes of underground water ice found near the moon's poles. Proponents of a practice called in situ resource utilization hope that this ice can be split into hydrogen and oxygen to fuel rockets leaving the moon, which would dramatically reduce the cost of roundtrip missions. But the poles are also more challenging areas to land, which is why many moon missions have stuck to more equatorial landing sites.
NASA has now selected some of the first Artemis program payloads as well as the first three lander providers, but has not yet determined which payloads will fly on which landers — and hence, which payloads will land at which sites.
Some of the science topics the instruments are designed to focus on include the magnetic field, the wispy atmosphere scientists call an exosphere, the surface composition and the landing process itself. NASA has also selected two technology demonstration projects, one a solar array and one a navigational beacon.
This early in the process of returning to the moon, NASA representatives believe that landing the instruments at all is more important than targeting the south pole and other key regions specifically.
"We learn a lot everywhere on the moon that will help us with future human landings," Chris Culbert, Commercial Lunar Payload Services program manager at NASA's Johnson Space Center in Houston, said during a media call held later on May 31. "We'll get value out of all these payloads, no matter where they go."
Email Meghan Bartels at mbartels@space.com or follow her @meghanbartels. Follow us on Twitter @Spacedotcom and on Facebook.
https://www.space.com/nasa-commercial-moon-landing-sites-target.html
2019-06-09 12:07:00Z
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