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.

NASA Seeks More Lunar Science, Technology Experiments for Artemis Program

With five robotic flights to the Moon already booked through 2023, and a sixth award expected soon, NASA is seeking suites of new science investigations and technology experiments for future commercial lunar deliveries as part of the Artemis program.

The agency issued its Payloads and Research Investigations on the Surface of the Moon (PRISM) Nov. 5, for payloads to be delivered on flights to the lunar surface in late 2023 and early 2024. This call for payloads is expected to be the first of an annual call for payloads that will make up the Science Mission Directorate’s portion of the manifest for future flights within the agency’s Commercial Lunar Payloads Services, or CLPS, initiative.

“Demand for access to the Moon is rapidly increasing as our Artemis program takes shape, and we’re proud to support a growing lunar economy with our CLPS project,” said Thomas Zurbuchen, associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. “We’re on track for two flights to the Moon per year, with the first six already ordered or soon awarded. This new call will enable breakthrough science, and especially advance our understanding of the Moon ahead of a human return in 2024.”

The formal PRISM solicitation builds on an earlier Request for Information that requested payload concepts from the U.S. science community for lunar surface investigations. Responses to this RFI informed and guided upcoming solicitations for opportunities to send instruments to the Moon. NASA is seeking science-driven suites of instruments and technology demonstrations for delivery to the Reiner Gamma (lunar magnetic anomaly on the lunar near side) in 2023 and the Schrödinger Basin (impact melt on the lunar far side) of the Moon in 2024.

For the initial phase, Step 1 responses to the solicitation are due Dec. 11, 2020. Proposals must identify only one of the two offered locations. Some technology development and maturation within the proposed project is allowed, but the science justification and ability to deliver on schedule are top considerations for selection. Additional details are available in the formal solicitation online.

As part of the CLPS project, NASA has already made the following awards:

2021

    • Astrobotic and Intuitive Machines each have one task order award for deliveries in 2021. Astrobotic will carry 11 payloads to Lacus Mortis, a larger crater on the near side of the Moon, and Intuitive Machines will carry five payloads to the southwest portion of Mare Serenitatis, near the Montes Apenninus region on the Moon.

2022

    • Masten Space Systems has one task order award to deliver and operate eight payloads – with nine science and technology instruments – to the lunar South Pole.
    • NASA awarded Intuitive Machines a task order to deliver the PRIME-1 drill and mass spectrometer to the Moon by December of 2022.

2023

    • NASA awarded a task order to Astrobotic to deliver the agency’s VIPER rover to the lunar South Pole in late 2023.
    • By the end of the year NASA will select a vendor to deliver a suite of payloads to study geophysics within the Mare Crisium basin on the Moon in 2023.

NASA and its partners will continue to study and explore more of the Moon in the coming years as part of the Artemis program. The agency continues to advance its modern lunar exploration program and is preparing to establish a sustainable presence at the lunar South Pole by the end of the decade. Knowledge gained on and around the Moon will help prepare the agency for its next giant leap in exploration – human exploration of Mars.

Earth's Moon
Credit: NASA

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.