NASA administrator Jim Bridenstine said Friday he is “very confident” in a potential November 2021 launch for the large Space Launch System rocket.

While expressing confidence in this date, however, Bridenstine added that there are uncertainties between now and then. One is technical—the core stage of the SLS rocket must undergo a series of tests this summer and autumn before it moves to the launch pad. The second issue is the ongoing COVID-19 pandemic, which is spiking around several NASA centers.

Green Run test

In January, NASA and the contractor for the SLS rocket’s core stage, Boeing, moved the vehicle to Stennis Space Center in southern Mississippi. Since then, workers have been putting the stage—which consists of four space shuttle main engines and very large tanks to store liquid hydrogen and liquid oxygen propellants—through a series of tests.

This week, Boeing officials said they expect to conduct the final, and most important, of those tests in October: lighting all four of the rocket’s engines and firing them for about eight minutes to mimic an actual launch.

If this test is successful, the core stage will then be moved by barge to Kennedy Space Center, likely in early 2021. After that point, two side-mounted boosters will be added, along with an upper stage and the Orion spacecraft. This full stack will then undergo further tests before finally launching on an uncrewed test flight. A late 2021 launch date assumes all of these activities go forward as planned, which is far from certain when dealing with a new rocket.

Pandemic worries

On Friday, Bridenstine also expressed concern about the COVID-19 pandemic. Appearing on a webinar produced by Aviation Week, he said the virus has the potential to impact schedules for all of NASA’s programs, including SLS.

“I think we’re OK for now, but if we don’t get a grip on the coronavirus pandemic in the near future, it’s going to be difficult,” Bridenstine said. “If the coronavirus pandemic is not an issue, then I’m very confident in November 2021.”

NASA’s major human spaceflight centers—in Texas, Florida, and Alabama—are all within states seeing rapid growth in COVID-19 cases. The situation in Mississippi is not great either, with the rolling, seven-day average more than quadrupling over the last month to more than 800 cases per day. Stennis was shut down for a couple of months this spring due to the pandemic but has since reopened.

Bridenstine said that, when an employee at Stennis tests positive, it can shut down operations, perhaps for a week, to assess the situation and perform contact tracing. If that happens enough, he said, it will eat through the margin built into the schedule to complete testing at the large Mississippi test stand this year.

https://arstechnica.com/?p=1692677