CAPSTONE is the first cubesat ever to reach Earth's nearest neighbor.

A tiny NASA spacecraft's historic trek to the moon is over.

The 55-pound (25 kilograms) CAPSTONE probe slipped into orbit around the moon on Sunday evening (Nov. 13), becoming the first cubesat ever to visit Earth's nearest neighbor.

The milestone came after a successful engine burn that ended at 7:39 p.m. EST (0039 GMT on Nov. 14), NASA officials said in a brief update(opens in new tab).

The maneuver put CAPSTONE (short for "Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment") into a near-rectilinear halo orbit (NRHO) around the moon, a highly elliptical path that will also be occupied by NASA's Gateway space station.

NASA plans to launch the first pieces of Gateway, a crucial part of its Artemis program of moon exploration, in 2024. But the agency wants to learn more about lunar NRHOs first, and that's where CAPSTONE comes in: The microwave-oven-sized spacecraft will verify the suspected stability of this orbit, which a spacecraft has never flown in before, during a mission designed to last at least six months.

CAPSTONE will also perform some communication and navigation tests, some of them in concert with NASA's Lunar Reconnaissance Orbiter, which has been looping around the moon since 2009.

CAPSTONE isn't ready to get to work just yet, however; it still needs to fine-tune its path around the moon.

"Two smaller correction maneuvers will take place this week to ensure the spacecraft is confirmed into the complex lunar orbit," representatives of the Colorado company Advanced Space, which owns CAPSTONE and operates the cubesat for NASA, wrote in an update Sunday night(opens in new tab).

CAPSTONE's path to lunar orbit was a bit bumpy. The probe launched atop a Rocket Lab Electron booster on June 28, kicking off a circuitous, highly fuel-efficient 4.5-month-long trek that followed gravitational contours.

The CAPSTONE team lost contact with the probe on July 4, just after it separated from Rocket Lab's Photon spacecraft bus. They quickly identified and fixed the problem, an improperly formatted command, getting CAPSTONE back on track the next day.

CAPSTONE ran into more trouble two months later. The probe suffered a glitch during a trajectory-correcting engine burn on Sept. 8; it began to tumble and went into a protective safe mode as a result. 

The mission team traced this problem to a wonky valve in CAPSTONE's propulsion system, troubleshot it, and got the probe back on course for its historic lunar arrival.

Other cubesats will soon follow in CAPSTONE's footsteps, if all goes according to plan. NASA's Artemis 1 moon mission is scheduled to launch on Nov. 16, sending the agency's Orion capsule on an uncrewed shakeout cruise to lunar orbit. Artemis 1 will also loft 10 ride-along cubesats, some of which will study the moon. 

One of those little craft, Japan's OMOTENASHI ("Outstanding Moon exploration Technologies demonstrated by Nano Semi-Hard Impactor"), will even put a tiny lander down on the moon.

Though CAPSTONE is a lunar trailblazer, it isn't the first cubesat to go beyond Earth orbit. That distinction goes to NASA's MarCO-A and MarCO-B probes, also known as Wall-E and Eva, which launched with the agency's InSight Mars lander in May 2018. The two cubesats helped beam home data during InSight's Red Planet touchdown six months later and also managed to photograph Mars.

Quelle: SC

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Update: 23.11.2022

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CAPSTONE Forges New Path for NASA’s Future Artemis Moon Missions

NASA's CAPSTONE spacecraft has completed final maneuvers to place it in its target orbit around the Moon, refining its path in the orbit it arrived to last week.

The spacecraft now is in the operational phase of its pathfinding mission, during which it will test an orbit key to future Artemis missions and demonstrate new technologies for spacecraft operating near the Moon.

“NASA’s partnership with Advanced Space on CAPSTONE is enabling NASA to gain critical, additional capabilities at a lower cost,” said NASA Administrator Bill Nelson. “CAPSTONE is part of our new era of human exploration at the Moon, testing the unique orbit planned for the Gateway lunar space station.”

CAPSTONE – short for Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment – is a technology demonstration, designed to prove the reliability of new capabilities so that they can be used in future missions. CAPSTONE is the first spacecraft to fly in a near-rectilinear halo orbit (NRHO) and the first CubeSat to operate at the Moon. This orbit is the same planned for Gateway, an upcoming Moon-orbiting space station that will support NASA's Artemis missions. CAPSTONE will gather data on this orbit for at least six months to support Gateway's operational planning.

"Missions like CAPSTONE allow us to reduce risk for future spacecraft, giving us a chance to test our understanding and demonstrate technologies we intend to use in the future," said Jim Reuter, associate administrator for NASA's Space Technology Mission Directorate. "Partnering with innovative U.S. companies, including several small businesses, on CAPSTONE has given us the chance to forge new ground, merging commercial interests with NASA's goals."  

CAPSTONE took a four-month journey from launch to orbit – overcoming challenges related to communications and propulsion along the way – and performed an initial orbit insertion maneuver on Nov. 13. In the following days, the CAPSTONE mission operations team, led by Advanced Space of Westminster, Colorado, analyzed data from the spacecraft to confirm it was in the expected orbit and carried out two clean-up maneuvers to refine its track.

In addition to studying this unique orbit, CAPSTONE's mission also includes two technology demonstrations that could be used by future spacecraft. The Cislunar Autonomous Positioning System, or CAPS, is a navigational software developed by Advanced Space that would allow spacecraft operating near the Moon to determine their position in space without relying exclusively on tracking from Earth. CAPSTONE will demonstrate this technology by communicating directly with NASA's Lunar Reconnaissance Orbiter, which has been in orbit around the Moon since 2009. CAPSTONE will also demonstrate one-way ranging using a chip-scale atomic clock, which could allow spacecraft to determine their position in space without the need for a dedicated downlink to ground stations.

"We have been working to this point since we started the company over 11 years ago. Getting into this orbit at the Moon validates so much hard work and grit by the combined CAPSTONE mission operations team," said Bradley Cheetham, principal investigator for CAPSTONE and chief executive officer of Advanced Space. "The capabilities we have demonstrated and the technologies still to be matured will support future missions for decades to come."

CAPSTONE launched June 28, 2022, aboard a Rocket Lab Electron rocket from Mahia, New Zealand. After launch, a Photon upper stage raised CAPSTONE's orbit and injected the spacecraft into its ballistic lunar transfer, a long but fuel-efficient trajectory that carried the spacecraft to the Moon over the course of more than four months.

CAPSTONE is commercially owned and operated by Advanced Space. It represents an innovative collaboration between NASA and industry to provide rapid results and feedback to inform future exploration and science missions. The spacecraft was designed and built by Terran Orbital. Operations are performed jointly by teams at Advanced Space and Terran Orbital. The mission is also supported by Stellar Exploration, Space Dynamics Laboratory, Orion Space Solutions, Tethers Unlimited, Inc., and Morehead State University.

NASA’s Small Spacecraft Technology program within the agency’s Space Technology Mission Directorate (STMD) funds the demonstration mission. The program is based at NASA’s Ames Research Center in California’s Silicon Valley. The development of CAPSTONE’s navigation technology is supported by NASA’s Small Business Innovation Research and Small Business Technology Transfer (SBIR/STTR) program, also within STMD. The Artemis Campaign Development Division within NASA’s Exploration Systems Development Mission Directorate funded the launch and supports mission operations.

Quelle: NASA