Thursday, 18 August, 2022

Scitech space

NASA plans new Moon mission

In the coming years, NASA will be busy at the moon. A giant rocket will loft a capsule with no astronauts aboard around the moon and back, perhaps before the end of summer.

A parade of robotic landers will drop off experiments on the moon to collect reams of scientific data, especially about water ice locked up in the polar regions. A few years from now, astronauts could return there, more than a half-century since the last Apollo moon landing, according to an article at New York Times.

Those are all part of NASA’s 21st-century moon program named for Artemis, who in Greek mythology was the twin sister of Apollo.

Early Monday, a spacecraft named CAPSTONE is scheduled to launch as the first piece of Artemis to head to the moon. Compared to what is to follow, it is modest in size and scope. There will not be any astronauts aboard CAPSTONE. The spacecraft is too tiny, about as big as a microwave oven.

This robotic probe won’t land on the moon. But it is in many ways unlike any previous mission to the moon. It could serve as a template for public-private partnerships that NASA could undertake in the future to get a better bang for its buck on interplanetary voyages.

“NASA has gone to the moon before, but I’m not sure it’s ever been put together like this,” said Bradley Cheetham, CEO and president of Advanced Space, the company that is managing the mission for NASA.

Coverage of the launch will be begin at 5 a.m. Eastern time Monday on NASA Television. The rocket has to launch at an exact moment, at 5:50 a.m., for the spacecraft to be lofted to the correct trajectory.

The full name of the mission is the Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment. It will act as a scout for the lunar orbit where a crewed space station will eventually be built as part of Artemis. That outpost, named Gateway, will serve as a way station where future crews will stop before continuing on to the lunar surface.

CAPSTONE is unusual for NASA in several ways. For one, it is sitting on a launchpad not in Florida but in New Zealand. Second, NASA did not design or build CAPSTONE, nor will it operate it. The agency does not even own it. CAPSTONE belongs to Advanced Space, a 45-employee company on the outskirts of Denver.

The spacecraft is taking a slow but efficient trajectory to the moon, arriving Nov. 13. If weather or a technical problem causes the rocket to miss that instantaneous launch moment, there are additional chances through July 27. If the spacecraft gets off the ground by then, it will still get to lunar orbit on the same day: Nov 13.

The CAPSTONE mission continues efforts by NASA to collaborate in new ways with private companies in hopes of gaining additional capabilities at lower cost more quickly.

“It’s another way for NASA to find out what it needs to find out and get the cost down,” said Bill Nelson, NASA’s administrator.

Advance Space’s contract with NASA for CAPSTONE, signed in 2019, cost $20 million. The ride to space for CAPSTONE is small and cheap too: just under $10 million for a launch by Rocket Lab, a U.S.-New Zealand company that is a leader in delivering small payloads to orbit.

“It’s going to be under $30 million in under three years,” said Christopher Baker, program executive for small spacecraft technology at NASA. “Relatively rapid and relatively low cost.”

Even Beresheet, a shoestring effort by an Israeli nonprofit to land on the moon in 2019, cost $100 million. “I do see this as a pathfinder for how we can help facilitate commercial missions beyond Earth,” Baker said.

The primary mission of CAPSTONE is to last six months, with the possibility of an additional year, Cheetham said. The data it gathers will aid planners of the lunar outpost known as Gateway.

The first Artemis landing mission, which is scheduled for 2025 but likely to be pushed back, will not use Gateway. But subsequent missions will. NASA decided that the best place to put this outpost would be in what is known as a near-rectilinear halo orbit.

Halo orbits are those influenced by the gravity of two bodies — in this case, the Earth and the moon. The influence of the two bodies helps make the orbit highly stable, minimizing the amount of propellant needed to keep a spacecraft circling the moon.

The gravitational interactions also keep the orbit at about a 90-degree angle to the line-of-sight view from Earth. (This is the near-rectilinear part of the name.) Thus, a spacecraft in this orbit never passes behind the moon where communications would be cut off.