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    • By NASA
      Astronauts will test drive NASA’s Orion spacecraft for the first time during the agency’s Artemis II test flight next year. While many of the spacecraft’s maneuvers like big propulsive burns are automated, a key test called the proximity operations demonstration will evaluate the manual handling qualities of Orion.

      During the approximately 70-minute demonstration set to begin about three hours into the mission, the crew will command Orion through a series of moves using the detached upper stage of the SLS (Space Launch System) rocket as a mark. The in-space propulsion stage, called the ICPS (interim cryogenic propulsion stage), includes an approximately two-foot target that will be used to evaluate how Orion flies with astronauts at the controls.

      “There are always differences between a ground simulation and what an actual spacecraft will fly like in space,” said Brian Anderson, Orion rendezvous, proximity operations, and docking manager within the Orion Program at NASA’s Johnson Space Center in Houston. “The demonstration is a flight test objective that helps us reduce risk for future missions that involve rendezvous and docking with other spacecraft.”

      After NASA’s Reid Wiseman, Victor Glover, and Christina Koch, and CSA (Canadian Space Agency) astronaut Jeremy Hansen are safely in space, the Moon rocket’s upper stage will fire twice to put Orion on a high Earth orbit trajectory. Then, the spacecraft will automatically separate from the rocket stage, firing several separation bolts before springs push Orion a safe distance away.

      As the spacecraft and its crew move away, Orion will perform an automated backflip to turn around and face the stage. At approximately 300 feet away, Orion will stop its relative motion. The crew will take control and use the translational and rotational hand controllers and display system to make very small movements to ensure Orion is responding as expected.

      Next, the crew will very slowly pilot Orion to within approximately 30 feet of the stage. A two-foot auxiliary target mounted inside the top of the stage, similar to the docking target used by spacecraft visiting the International Space Station, will guide their aim.

      “The crew will view the target by using a docking camera mounted inside the docking hatch window on the top of the crew module to see how well aligned they are with the docking target mounted to the ICPS,” Anderson said.
      “It’s a good stand in for what crews will see when they dock with Starship on Artemis III and to the Gateway on future missions.”

      About 30 feet from the stage, Orion will stop and the crew will checkout the spacecraft’s fine handling qualities to evaluate how it performs in close proximity to another spacecraft. Small maneuvers performed very close to the ICPS will be done using the reaction control system thrusters on Orion’s European Service Module.

      Orion will then back away and allow the stage to turn to protect its thermal properties. The crew will follow the stage, initiate a second round of manual maneuvers using another target mounted on the side of the stage, approach within approximately 30 feet, perform another fine handling quality check out, then back away.

      At the end of the demonstration, Orion will perform an automated departure burn to move away from the ICPS before the stage then fires to re-enter Earth’s atmosphere over a remote location in the Pacific Ocean. During Orion’s departure burn, engineers will use the spacecraft’s docking camera to gather precise positioning measurements, which will help inform navigation during rendezvous activities on future missions in the lunar environment, where there is no GPS system. 

      Because the Artemis II Orion is not docking with another spacecraft, it is not equipped with a docking module containing lights and therefore is reliant on the ICPS to be lit enough by the Sun to allow the crew to see the targets.

      “As with many of our tests, it’s possible the proximity operations demonstration won’t go exactly as expected,” said Anderson. “Even if we don’t accomplish every part of the demonstration, we’ll continue on with the test flight as planned to accomplish our primary objectives, including evaluating Orion’s systems with crew aboard in the deep space environment and keeping the crew safe during the mission.”

      The approximately 10-day Artemis II flight will test NASA’s foundational human deep space exploration capabilities, the SLS rocket and Orion spacecraft, for the first time with astronauts and will pave the way for lunar surface missions, including landing the first woman, first person of color, and first international partner astronaut on the Moon.



      View the full article
    • By NASA
      The asteroid Dimorphos was captured by NASA’s DART mission just two seconds before the spacecraft struck its surface on Sept. 26, 2022. Observations of the asteroid before and after impact suggest it is a loosely packed “rubble pile” object.NASA/Johns Hopkins APL After NASA’s historic Double Asteroid Redirection Test, a JPL-led study has shown that the shape of asteroid Dimorphos has changed and its orbit has shrunk.
      When NASA’s DART (Double Asteroid Redirection Test) deliberately smashed into a 560-foot-wide (170-meter-wide) asteroid on Sept. 26, 2022, it made its mark in more ways than one. The demonstration showed that a kinetic impactor could deflect a hazardous asteroid should one ever be on a collision course with Earth. Now a new study published in the Planetary Science Journal shows the impact changed not only the motion of the asteroid, but also its shape.
      DART’s target, the asteroid Dimorphos, orbits a larger near-Earth asteroid called Didymos. Before the impact, Dimorphos had a roughly symmetrical “oblate spheroid” shape – like a squashed ball that is wider than it is tall. With a well-defined, circular orbit at a distance of about 3,900 feet (1,189 meters) from Didymos, Dimorphos took 11 hours and 55 minutes to complete one loop around Didymos.
      “When DART made impact, things got very interesting,” said Shantanu Naidu, a navigation engineer at NASA’s Jet Propulsion Laboratory in Southern California, who led the study. “Dimorphos’ orbit is no longer circular: Its orbital period” – the time it takes to complete a single orbit – “is now 33 minutes and 15 seconds shorter. And the entire shape of the asteroid has changed, from a relatively symmetrical object to a ‘triaxial ellipsoid’ – something more like an oblong watermelon.”
      This illustration shows the approximate shape change that the asteroid Dimorphos experienced after DART hit it. Before impact, left, the asteroid was shaped like a squashed ball; after impact it took on a more elongated shape, like a watermelon.NASA/JPL-Caltech Dimorphos Damage Report
      Naidu’s team used three data sources in their computer models to deduce what had happened to the asteroid after impact. The first source was aboard DART: The spacecraft captured images as it approached the asteroid and sent them back to Earth via NASA’s Deep Space Network (DSN). These images provided close-up measurements of the gap between Didymos and Dimorphos while also gauging the dimensions of both asteroids just prior to impact.
      The second data source was the DSN’s Goldstone Solar System Radar, located near Barstow, California, which bounced radio waves off both asteroids to precisely measure the position and velocity of Dimorphos relative to Didymos after impact. Radar observations quickly helped NASA conclude that DART’s effect on the asteroid greatly exceeded the minimum expectations.
      The third and most significant source of data: ground telescopes around the world that measured both asteroids’ “light curve,” or how the sunlight reflecting off the asteroids’ surfaces changed over time. By comparing the light curves before and after impact, the researchers could learn how DART altered Dimorphos’ motion.
      As Dimorphos orbits, it periodically passes in front of and then behind Didymos. In these so-called “mutual events,” one asteroid can cast a shadow on the other, or block our view from Earth. In either case, a temporary dimming – a dip in the light curve – will be recorded by telescopes.
      See the DART impact with NASA’s Eyes on the Solar System “We used the timing of this precise series of light-curve dips to deduce the shape of the orbit, and because our models were so sensitive, we could also figure out the shape of the asteroid,” said Steve Chesley, a senior research scientist at JPL and study co-author. The team found Dimorphos’ orbit is now slightly elongated, or eccentric. “Before impact,” Chesley continued, “the times of the events occurred regularly, showing a circular orbit. After impact, there were very slight timing differences, showing something was askew. We never expected to get this kind of accuracy.”
      The models are so precise, they even show that Dimorphos rocks back and forth as it orbits Didymos, Naidu said.
      Orbital Evolution
      The team’s models also calculated how Dimorphos’ orbital period evolved. Immediately after impact, DART reduced the average distance between the two asteroids, shortening Dimorphos’ orbital period by 32 minutes and 42 seconds, to 11 hours, 22 minutes, and 37 seconds.
      Over the following weeks, the asteroid’s orbital period continued to shorten as Dimorphos lost more rocky material to space, finally settling at 11 hours, 22 minutes, and 3 seconds per orbit – 33 minutes and 15 seconds less time than before impact. This calculation is accurate to within 1 ½ seconds, Naidu said. Dimorphos now has a mean orbital distance from Didymos of about 3,780 feet (1,152 meters) – about 120 feet (37 meters) closer than before impact.
      “The results of this study agree with others that are being published,” said Tom Statler, lead scientist for solar system small bodies at NASA Headquarters in Washington. “Seeing separate groups analyze the data and independently come to the same conclusions is a hallmark of a solid scientific result. DART is not only showing us the pathway to an asteroid-deflection technology, it’s revealing new fundamental understanding of what asteroids are and how they behave.”
      These results and observations of the debris left after impact indicate that Dimorphos is a loosely packed “rubble pile” object, similar to asteroid Bennu. ESA’s (European Space Agency) Hera mission, planned to launch in October 2024, will travel to the asteroid pair to carry out a detailed survey and confirm how DART reshaped Dimorphos.
      More About the Mission
      DART was designed, built, and operated by the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, for NASA’s Planetary Defense Coordination Office, which oversees the agency’s ongoing efforts in planetary defense. DART was humanity’s first mission to intentionally move a celestial object.
      JPL, a division of Caltech in Pasadena, California, manages the DSN for NASA’s Space Communications and Navigation (SCaN) program within the Space Operations Mission Directorate at the agency’s headquarters in Washington.
      NASA’s Asteroid-Striking DART Mission Team Has JPL Members Classroom Activity: How to Explore an Asteroid NASA’s Planetary Radar Captures Detailed View of Oblong Asteroid News Media Contacts
      Ian J. O’Neill
      Jet Propulsion Laboratory, Pasadena, Calif.
      818-354-2649
      ian.j.oneill@jpl.nasa.gov
      Karen Fox / Charles Blue
      NASA Headquarters
      karen.c.fox@nasa.gov / charles.e.blue@nasa.gov
      2024-029
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      Last Updated Mar 19, 2024 Related Terms
      DART (Double Asteroid Redirection Test) Asteroids Jet Propulsion Laboratory Modeling Near-Earth Asteroid (NEA) Planetary Defense Planetary Defense Coordination Office Explore More
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    • By European Space Agency
      ESA’s Arctic Weather Satellite has passed its environmental test campaign with flying colours – meaning that the satellite has been declared fit for liftoff and its life in the harsh environment of space.
      This new satellite, which is slated for launch in June, has been designed to show how it can improve weather forecasts in the Arctic – a region that currently lacks data for accurate short-term forecasts.
      View the full article
    • By NASA
      NASA/Sam Lott A test version of the universal stage adapter for NASA’s more powerful version of its SLS (Space Launch System) rocket arrived to Building 4619 at NASA’s Marshall Space Flight Center in Huntsville, Alabama, Feb. 22 from Leidos in Decatur, Alabama. The universal stage adapter will connect the rocket’s upgraded in-space propulsion stage, called the exploration upper stage, to NASA’s Orion spacecraft as part of the evolved Block 1B configuration of the SLS rocket. It will also serve as a compartment capable of accommodating large payloads, such as modules or other exploration spacecraft. The SLS Block 1B variant will debut on Artemis IV and will increase SLS’s payload capability to send more than 84,000 pounds to the Moon in a single launch.
      In Building 4619’s Load Test Annex High Bay at Marshall, the development test article will first undergo modal testing that will shake the hardware to validate dynamic models. Later, during ultimate load testing, force will be applied vertically and to the sides of the hardware. Unlike the flight hardware, the development test article has flaws intentionally included in its design, which will help engineers verify that the adapter can withstand the extreme forces it will face during launch and flight. The test article joins an already-rich history of rocket hardware that has undergone high-and-low pressure, acoustic, and extreme temperature testing in the multipurpose, high-bay test facility; it will be tested in the same location that once bent, compressed, and torqued the core stage intertank test article for SLS rocket’s Block 1 configuration. Leidos, the prime contractor for the universal stage adapter, manufactured the full-scale prototype at its Aerospace Structures Complex in Decatur.
      NASA is working to land the first woman, first person of color, and its first international partner astronaut on the Moon under Artemis. SLS is part of NASA’s backbone for deep space exploration, along with the Orion spacecraft and Gateway in orbit around the Moon and commercial human landing systems, next-generational spacesuits, and rovers on the lunar surface. SLS is the only rocket that can send Orion, astronauts, and supplies to the Moon in a single launch.
      News Media Contact
      Corinne Beckinger
      Marshall Space Flight Center, Huntsville, Ala.
      256.544.0034
      corinne.m.beckinger@nasa.gov
      View the full article
    • By NASA
      SXSW 2024: NASA Astronauts & Your Work in Orbit
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