If you would like to see more articles like this please support our coverage of the space program by becoming a Spaceflight Now Member . If everyone who enjoys our website helps fund it, we can expand and improve our coverage further.

NASA announced Thursday that work on the Space Launch System heavy-lift rocket and Orion crew capsule at facilities in Louisiana and Mississippi is being halted due to the spreading coronavirus pandemic, a stoppage that could force further delays on the already behind-schedule and over-budget programs.

Meanwhile, NASA officials said Thursday they are making plans to try and keep the agency’s next Mars rover and the multibillion-dollar James Webb Space Telescope on schedule for launches in later this year and in 2021.

NASA has elevated the Stennis Space Center in Mississippi and the Michoud Assembly Facility in Louisiana to Stage 4 of the agency’s Response Framework, forcing the closure of both sites to nearly all employees, effective Friday.

At Stennis, NASA and Boeing teams were readying the core stage of NASA’s Space Launch System for a series of critical tests in the coming months, culminating in a test-firing of the rocket’s four main engines that had been scheduled for early August. With the shutdown of Stennis, that testing will be delayed.

SLS core stages are manufactured at the Michoud plant in New Orleans, and pressure vessels of Orion crew capsules are welded there. The SLS and Orion vehicles are the centerpieces of NASA’s Artemis program, which aims to land astronauts at the moon’s south pole before the end of 2024, a goal that was already widely considered ambitious.

NASA Administrator Jim Bridenstine said a Stennis employee has tested positive for the COVID-19 coronavirus.

“The change at Stennis was made due to the rising number of COVID-19 cases in the community around the center, the number of self-isolation cases within our workforce there, and one confirmed case among our Stennis team,” Bridenstine said in a statement. “While there are no confirmed cases at Michoud, the facility is moving to Stage 4 due to the rising number of COVID-19 cases in the local area, in accordance with local and federal guidelines.”

The only other NASA center elevated to Stage 4 to date is the Ames Research Center in California. All other agency facilities are at Stage 3, where only “mission-essential” personnel are allowed to work on site.

With the elevation of Stennis and Michoud to Stage 4, only employees “required to maintain the safety and security of the center” will come to work. All other staff at Stennis and Michoud will work remotely.

“Additionally, all travel is suspended,” Bridenstine said late Thursday. “These measures are being taken to help slow the transmission of COVID-19 and protect our communities.”

Bridenstine confirmed the decision to effectively shut down operations Stennis and Michoud will affect the SLS and Orion programs.

“NASA will temporarily suspend production and testing of Space Launch System and Orion hardware,” Bridenstine said. “The NASA and contractors teams will complete an orderly shutdown that puts all hardware in a safe condition until work can resume. Once this is complete, personnel allowed onsite will be limited to those needed to protect life and critical infrastructure.

“We realize there will be impacts to NASA missions, but as our teams work to analyze the full picture and reduce risks we understand that our top priority is the health and safety of the NASA workforce,” he said.

The SLS core stage currently on the test stand at Stennis is slated to lift off next year on the Artemis 1 mission, an unpiloted test flight carrying an Orion spacecraft to lunar orbit and back to Earth. Boeing, the core stage’s prime contractor, finished assembly of the 212-foot-long (65-meter) rocket structure late last year.

At the end of 2019, NASA had obligated $14.8 billion on the SLS program, with the rocket’s inaugural launch still more than a year way, the agency’s inspector general reported earlier this month.

The first SLS core stage rolled out of the Michoud factory in January and rode a NASA barge to the Stennis Space Center in southern Mississippi for a series of control system checkouts, a cryogenic fueling test, and a full-duration firing of all four engines, which are leftovers from the space shuttle program.

The Orion spacecraft for the Artemis 1 mission recently completed a battery of thermal vacuum and electromagnetic tests inside a giant chamber at NASA’s Plum Brook Station in Ohio.

The Orion spacecraft, comprised of a U.S.-made crew module and a European-built service module, was scheduled to ride a NASA transport plane from Ohio to the Kennedy Space Center on March 24 to begin final preparations for liftoff next year. As of Wednesday, the spacecraft’s arrival back in Florida was still scheduled for March 24, but an update on the transport plans was not immediately available Thursday night.

Meanwhile, production of core stages for future SLS rockets is underway at Michoud. That work will be suspended now that Michoud has been elevated to Stage 4 status.

The Space Launch System and Orion are two of NASA’s largest programs.

NASA and its international partners are expected to continue operations aboard the International Space Station, which has been home to astronauts continuously since 2000. The station’s next three-man crew is scheduled for launch April 9 on a Russian Soyuz rocket from the Baikonur Cosmodrome in Kazakhstan.

NASA said Wednesday that the first piloted test flight of SpaceX’s Crew Dragon capsule, developed with NASA funding, is scheduled for launch in mid-to-late May from the Kennedy Space Center in Florida. NASA astronauts Doug Hurley and Bob Behnken are training for the mission, which will dock with the space station.

The liftoff of the Crew Dragon spacecraft on top of a Falcon 9 rocket will be the first launch of astronauts into orbit from a U.S. spaceport since the retirement of the space shuttle in July 2011.

NASA said it would follow guidance from the Centers for Disease Control and Prevention and the agency’s chief health and medical officer for updates that may impact the Crew Dragon mission.

“I will continue to say, so none of us forget – there is no team better prepared for doing hard things,” Bridenstine said. “Take care of yourself, your family, and your NASA team.”

NASA plans to continue work on Mars rover, James Webb Space Telescope

The coronavirus pandemic could have far-reaching impacts across a range of NASA missions, but agency officials said Thursday they will attempt to insulate two of NASA’s most critical robotic science missions from delays caused by COVID-19-related closures.

Lori Glaze, head of NASA’s planetary science division, said the Perseverance rover remains on schedule for liftoff during a limited 20-day window opening July 17. If the mission — also known as Mars 2020 — misses this summer’s launch window, the next chance to send the rover to Mars won’t be until 2022, a delay that could add to the $2.5 billion mission’s price tag.

“We’ve put together a framework … with which to look at each of the missions and what points we want to continue working on them,” Glaze said in a virtual town hall meeting Thursday with members of the planetary science community. “And Mars 2020 is one of only two missions within (NASA’s science directorate) that is the very highest priority … We’re going to ensure that we meet that launch window in July.

“In so doing, we’re also making sure that our personnel are healthy and safe,” Glaze said. “We’re taking every precaution to make sure that those individuals that are working on Mars 2020 are going to work in conditions and have an environment where they’re able to stay safe. But we’re continuing the activities, the integration and test activities, that are going on at Kennedy Space Center.”

The Perseverance rover arrived at the Kennedy Space Center last month from NASA’s Jet Propulsion Laboratory in California. Inside a pristine, climate-controlled clean room at the Florida spaceport, the rover will be installed on its landing platform and attached to a cruise stage that will carry it from Earth to Mars.

Then the spacecraft will be enclosed within the nose cone of a United Launch Alliance Atlas 5 rocket and trucked to the Atlas 5’s seaside launch complex for lifting atop the vehicle. Once in place, teams will add the rover’s plutonium power generator.

Glaze said members of the Mars 2020 team from KSC, JPL, NASA Headquarters and the Department of Energy — responsible for the nuclear power source — have given their “full support” for the plan.

“As of right now, and even if we go to a next stage of alert, Mars 2020 is moving forward on schedule and everything is so far very well on track,” Glaze said. “At this point, we don’t see any impact from the current situation.”

The Perseverance rover mission is one of two high-priority projects within NASA’s science division that are pre-approved to continue work even if the agency elevates all centers to Stage 4 in the coronavirus response plan.

The other mission is the James Webb Space Telescope, according to Grey Hautaluoma, a NASA spokesperson.

The Webb telescope is currently scheduled for launch in March 2021, but officials are expected to reassess that schedule in May after recent delays in testing at the observatory’s Northrop Grumman factory in California.

Glaze said Thursday that NASA is prioritizing work on missions with near-term launch dates.

Some delays will be inescapable.

Jim Reuter, head of NASA’s space technology mission directorate, said Thursday that the agency was planning to fly experiments in June on a suborbital launch by Blue Origin’a New Glenn rocket.

Given with situation with the coronavirus pandemic, which has strongly impacted areas around Blue Origin’s headquarters in Kent, Washington, a June launch of that mission is looking “pretty unlikely,” Reuter said.

Email the author.

Follow Stephen Clark on Twitter: @StephenClark1.