NASA Prepares for Next Series of RS-25 Engine Tests for SLS Rocket

NASA installed a developmental RS-25 engine into the test stand at Stennis Space Center near Bay St. Louis, Mississippi. This engine will be used in an upcoming test series to gather data and evaluate new components for development and production of new RS-25 engines for future Artemis missions. The new RS-25s, built by Aerojet Rocketdyne, will use advanced manufacturing methods and provide increased thrust levels, while also lowering manufacturing costs.

Engineers Move Forward with SLS Green Run Testing, Valve Repair Complete

Over the weekend, engineers at NASA’s Stennis Space Center near Bay St. Louis, Mississippi, successfully repaired a valve inside the core stage of the agency’s Space Launch System (SLS) rocket. The team designed an innovative tool to remove and replace the valve’s faulty clutch while the core stage remained in the B-2 test stand, and without removing the entire valve. Subsequent testing of the repaired valve confirmed that the system is operating as intended.

This week, the team is preparing for the seventh Green Run test, called the wet dress rehearsal, when the stage will be loaded with cryogenic, or super-cold, propellant for the first time. NASA is now targeting the week of Dec. 7 for the wet dress rehearsal and the week of Dec. 21 for the hot fire test. During the hot fire test, all four engines will fire to simulate the stage’s operation during launch. The Green Run test series is a comprehensive test of the rocket’s core stage before it launches Artemis missions to the Moon. NASA remains on track to launch Artemis I by November 2021.

Hurricane Zeta Impacts, SLS Green Run Testing Status Update

NASA has conducted an initial assessment of the impact from Hurricane Zeta at the agency’s Stennis Space Center near Bay St. Louis, Mississippi and Michoud Assembly Facility in New Orleans. While storm appraisals are continuing, teams have determined that Stennis did sustain some damage on the center, but the B-2 test stand and the Space Launch System (SLS) rocket’s core stage for Artemis I, currently in the stand, were not damaged. Michoud experienced damage to the outside and roof of buildings, but there is no damage to the SLS rocket or Orion spacecraft hardware being manufactured at the facility.

Widespread power outages in the area have made assessments difficult at both locations, and some buildings are still without power. While no personal injuries have been reported by NASA employees, many team members are also still without power, have experienced damage to personal property, and have not been able to return to work. Despite stopping work for the pandemic, as well as six Gulf Coast storms, and while working under pandemic-imposed restrictions, NASA and contractors Boeing and Aerojet Rocketdyne continue to make progress on Green Run testing of the SLS core stage at Stennis.

NASA has completed six of the eight core stage Green Run tests and is in the final stage of testing, which will operate the entire stage and its propulsion systems together for the first time. During the pause of on-site work due to the storm, engineers were able to take a closer look at data from recent testing. The team identified one of eight valves, which supply liquid hydrogen to the RS-25 engines, had inconsistent performance during recent tests. The valve is called a prevalve and is part of the core stage main propulsion system. NASA conducts ground testing on the core stage to demonstrate it is ready for flight, and the expert team of problem solvers is prepared to resolve any issues. Engineers have inspected the valve, understand the reason it is not working properly, and plan to repair the valve while the core stage remains in the B-2 test stand. Following a successful repair, the team plans to conduct the Green Run wet dress rehearsal and hot fire testing before the end of the year.

NASA is testing the new core stage on the ground to identify issues before flight, as the agency has done with every new rocket stage ever flown. The Green Run test series is a comprehensive test of the rocket’s core stage before it launches Artemis missions to the Moon. Check back at this blog for an update on completion of the repair and an updated schedule for the final Green Run tests.

Lunar Living: NASA’s Artemis Base Camp Concept

NASA’s Artemis program has sparked excitement around the world and catalyzed new interest in exploring the Moon as the agency prepares to land the first woman and next man on the lunar South Pole in 2024. After that, NASA and its growing list of global partners will establish sustainable exploration by the end of the decade.

NASA will build on the momentum of that human return mission in four years and plans to send crew to the Moon about once per year thereafter. To give astronauts a place to live and work on the Moon, the agency’s Artemis Base Camp concept includes a modern lunar cabin, a rover and even a mobile home. Early missions will include short surface stays, but as the base camp evolves, the goal is to allow crew to stay at the lunar surface for up to two months at a time.

“On each new trip, astronauts are going to have an increasing level of comfort with the capabilities to explore and study more of the Moon than ever before,” said Kathy Lueders, associate administrator for human spaceflight at NASA Headquarters in Washington. “With more demand for access to the Moon, we are developing the technologies to achieve an unprecedented human and robotic presence 240,000 miles from home. Our experience on the Moon this decade will prepare us for an even greater adventure in the universe – human exploration of Mars.” 

Where to stay

Crew will return to the lunar surface for the first time this century beginning with the Artemis III mission. From lunar orbit, two astronauts will take the first new ride to the surface of the Moon, landing where no humans have ever been: the lunar South Pole. This is the ideal location for a future base camp given its potential access to ice and other mineral resources.

On the first few missions, the human landing system will double as lunar lodging, offering life support systems to support a short crew stay on the Moon. In the future, NASA envisions a fixed habitat at the Artemis Base Camp that can house up to four astronauts for a month-long stay.

Since 2016, NASA has worked with several companies on their habitation systems and designs, assessing internal layouts, environmental control and life support systems, and outer structure options, including rigid shells, expandable designs, and hybrid concepts. The agency is currently working with industry to refine ideas for a combination home and office in orbit, recently testing full-size prototypes.

What to wear

Even with minimal surface support in place on early missions, astronauts will embark on at least a week-long expedition on the Moon. Crew will work by day in their modern spacesuits – using new tools to collect samples and setting up a variety of experiments.

These next generation spacesuits will provide increased mobility, modern communications and a more robust life support system than its Apollo predecessors. With improved functionality and movement, crew can conduct more complex experiments and collect more unique geologic samples.

NASA is building the new suits for the initial lunar landing and will transition the design and manufacturing to Industry for follow-on production.

Traveling in style

NASA has proposed two lunar surface transportation systems: a lunar terrain vehicle (LTV) and a mobile home and office referred to as a habitable mobility platform.

The LTV will be an unpressurized, or open-top vehicle, that astronauts can drive in their spacesuits for more than 12 miles from a camp site. Earlier this year, NASA asked American companies to send ideas to develop an LTV that handle the rough surface of the Moon as well as push the boundaries of power generation and energy storage. The agency is evaluating those responses and hopes to leverage innovations in commercial all-terrain vehicles, military rovers and more. Such a vehicle may also be autonomous and capable of driving on pre-programmed paths or could be operated remotely from Earth to conduct additional science and exploration activities.

In addition to the LTV, a pressurized rover will greatly expand lunar surface exploration capabilities to the next level. Pressurization means that astronauts can be in the vehicle in their regular clothing as opposed to wearing their spacesuit inside too. This will provide more comfort to work as they cross the lunar terrain in their mobile habitat and explore large areas. When they’re ready to go outside to collect samples or set up experiments, they would need to put their spacesuits on again.

NASA is in the early idea stage for a pressurized rover – formulating concepts and evaluating potential science and exploration rover missions around the South Pole.

What to do

Breakthrough discoveries from the Lunar Reconnaissance Orbiter and Lunar CRater Observation and Sensing Satellite have shown the Moon is rich with resources, such as ice and greater than average access to light, which could support Artemis explorers and provide new opportunities for scientific discoveries and commercial enterprising activities. The unexplored south polar region provides unique opportunities to unlock scientific secrets about the history and evolution of the Earth and Moon, as well as our solar system.

Harvesting lunar resources could lead to safer, more efficient operations with less dependence on supplies delivered from Earth. NASA plans to send the Volatiles Investigating Polar Exploration Rover (VIPER) to the lunar South Pole before crew. Arriving via a commercial Moon delivery, mobile robot will get a close-up view of the distribution and concentration of ice that could eventually be harvested to support human exploration farther into the solar system. We will learn how to spend more time on the lunar surface as well as prepare to future trips to Mars by conducting life science research and learning to mitigate hazards associated with space exploration.

What to know

The Sun hovers over the lunar South Pole horizon continuously throughout the day and year, providing a near-constant source of energy for solar power opportunities. There is no single location, however, that avoids periods of darkness. This means NASA must plan for early Artemis systems to survive the extremely cold environment without power, to build in the capability to store power for up to eight days.

For longer-term work trips to the Artemis Base Camp, NASA’s Lunar Surface Innovation Initiative is working with the U.S. Departments of Energy and Defense to develop a nuclear fission surface power unit that can continuously provide 10 kW of power – the average annual power consumption of a home here on Earth. This small power plant will be able to power and recharge the other basic elements of the Artemis Base Camp and allow greater flexibility for mission planning by easing the requirement for continuous access to sunlight in a distinct location during a specific timeframe.

What to pack

While NASA will need to bring or send ahead all the supplies it needs for early Artemis missions, the agency wants to know what others would pack for their trips to the Moon. It’s not too late to submit photos of your #NASAMoonKit online.

This decade, the Artemis program will lay the foundation for a sustained long-term presence on the lunar surface. As our lunar presence grows with the help of commercial and international partners, someday the Moon could be the ultimate destination for all to explore.

Illustration of NASA astronauts on the lunar South Pole.
Illustration of NASA astronauts on the lunar South Pole. Credit: NASA

 

SLS Green Run Testing Status Update

NASA is progressing through the Green Run test series for the Space Launch System (SLS) rocket at the agency’s Stennis Space Center in Mississippi and has completed six of the eight tests. The team is preparing to stand down for another tropical weather system that is heading to the area. The pause in work comes ahead of the most complex tests: wet dress rehearsal, when propellant will be loaded for the first time, and hot fire, when all four engines will be fired and every system within the stage will operate. During the pause, engineers will continue to assess data from recent tests to ensure the team is ready to proceed to the next phase of testing. Green Run testing is a complex series of tests to methodically and thoroughly check all the rocket’s core stage systems together for the first time to ensure the stage is ready for flight. Check back at this blog for an update on adjusted dates for the Green Run wet dress rehearsal and hot fire tests, after the storm has passed.

SLS Core Stage Passes Simulated Countdown Test

Engineers at NASA’s Stennis Space Center near Bay St. Louis, Mississippi, completed a simulated launch countdown sequence on Oct. 5 for the sixth test of the eight-part core stage Green Run test series for NASA’s Space Launch System (SLS) rocket.

The rocket’s core stage has three flight computers and avionics systems to help launch and guide NASA’s Artemis missions to the Moon. During the simulated countdown, NASA engineers and technicians, along with prime contractors Boeing, and Aerojet Rocketdyne, monitored the stage to validate the timeline and sequence of events leading up to the test, which is similar to the countdown for the Artemis I launch.

The countdown sequence for an actual Artemis launch begins roughly two days prior to liftoff. In addition to all the procedures leading up to the ignition of the four RS-25 engines, the SLS core stage requires about six hours to fully load fuel into the two liquid propellant tanks. The simulated countdown sequence test at Stennis began at the 48-hour mark as if the stage was first powered up before liftoff. Engineers then skipped ahead in the sequence to monitor the stage and procedures of the stage 10 minutes before the hot fire. The simulated countdown sequence is one of the final tests of the SLS Green Run campaign. The series of tests is designed to gradually bring the rocket stage and all its systems to life for the first time.

Artemis Plan to Land First Woman, Next Man on Moon in 2024

Following a series of critical contract awards and hardware milestones, an update on NASA’s Artemis program is now available, including the latest Phase 1 plans to land the first woman and the next man on the surface of the Moon in 2024.

In the 18 months since NASA accepted a bold challenge to accelerate its exploration plans by more than four years and establish sustainable exploration by the end of the decade, the agency has continued to gain momentum toward sending humans to the Moon again for the first time since the last Apollo mission in 1972.

The document captures Artemis progress to date, identifying the key science, technology and human missions as well as the commercial and international partnerships that will ensure we continue to lead in exploration and achieve our ambitious goal to land astronauts on the Moon.

>>Download and read the Artemis Plan

Artemis I Preparations Stack Up

Technicians with NASA’s Exploration Ground Systems rehearse booster stacking operations inside the Vehicle Assembly Building (VAB) at the agency’s Kennedy Space Center in Florida on Monday, Sept.14, in preparation for the Artemis I launch. The team is using full-scale replicas of booster segments, referred to as pathfinders, for the practice exercise in one of the tallest sections, or high bays, of the VAB built for stacking rockets. As part of the rehearsal, a pathfinder for an aft segment, the very bottom of the stack, was prepared in High Bay 4. Then, a team of crane operators moved the segment into High Bay 3, where it was placed on the mobile launcher. Careful measurements were taken before the team added a center segment to the stack.

The actual Space Launch System (SLS) booster segments will be stacked on the mobile launcher later this year, following completion of Green Run testing of the rocket’s core stage – a series of eight tests taking place at the agency’s Stennis Space Center in Mississippi.

NASA Completes Fifth Green Run Test for First Artemis Moon Rocket

Engineers have completed the fifth of eight Green Run tests on the core stage of NASA’s new Space Launch System (SLS) rocket, continuing progress toward a hot fire test this fall. Operators evaluated the stage’s thrust vector control system on the historic B-2 Test Stand at NASA’s Stennis Space Center near Bay St. Louis, Miss., on Sept. 13. The test provided critical verification of the control system and its related hydraulics as operators moved the stage’s four RS-25 engines as they must move during flight to steer the rocket and maintain a proper trajectory. The stage now is set for two more tests – a simulated countdown demonstration and wet dress rehearsal – directly leading to the hot fire of all four RS-25 engines, as during an actual flight.

In the countdown demonstration, engineers will simulate the launch countdown and procedures to validate the established timeline and sequence of events. In the wet dress rehearsal, engineers will conduct another countdown exercise and actually load, control and drain more than 700,000 gallons of cryogenic propellants to ensure all is set for the final test of the Green Run series. The concluding test will activate all stage systems and fire the four RS-25 engines to generate the same combined 1.6 million pounds of thrust that will help launch the SLS rocket when it flies on the Artemis I mission.

SLS Booster Test Update: Successful Test Completed!

Teams from NASA’s Space Launch System (SLS) and prime contractor Northrop Grumman successfully completed the Flight Support Booster-1 (FSB-1)  ground test at Northrop Grumman’s test facility in Promontory, Utah. Watch a replay of the test on NASA Television or NASA’s YouTube channel. Learn more about the test at https://www.nasa.gov/media/flight-support-booster-test.html