NASA is finally ready to launch its unmanned Orion spacecraft and put it in the orbit of the Moon. Lift-off from Earth is now expected in late August using a Space Launch System (SLS) rocket.
This launch, a mission dubbed Artemis I, will be a vital stage in the Artemis series, which has the long-term goal of ferrying humans to the lunar surface using Orion capsules and SLS technology.
Earlier this week NASA held a wet dress rehearsal (WDR) for the SLS vehicle – fueling it and getting within 10 seconds of launch. The test uncovered 13 problems, including a hydrogen fuel leak in the main booster, though NASA has declared that everything's fine for a launch next month.
At a press conference on Friday, NASA's Phil Weber, senior technical integration manager for the American space agency's Exploration Ground Systems Program (EGSP), said he was "on cloud nine" after testing earlier this week. We were told that "data from the rehearsal [has] determined the testing campaign is complete" during the presentation.
Planned to run down to T-10 seconds, the test launch on Monday was aborted at T-29 seconds due to a hydrogen leak in a quick disconnect port. Engineers tricked the rocket's control systems into letting the countdown continue despite the leak, and NASA described the experiment as successful, as teams "performed several critical operations that must be accomplished for launch."
The WDR this past Monday was also the first time NASA had fully loaded all of the craft's fuel tanks and proceeded into a terminal countdown; a WDR scheduled for April was scrapped due to "a faulty upper stage check valve and a small leak within the tail service mast umbilical ground plate housing," NASA said.
- NASA wants nuclear reactor on the Moon by 2030
- NASA tricks Artemis launch computer by masking data showing a leak
- Space Launch System dress rehearsal canceled for repairs
- NASA awaits approval of $24bn 2022 budget
"After looking at all the data from the WDR, we realized the test went even better than expected," Weber said, despite the failure in the hydrogen disconnect port. "We caught it quickly, and never broke launch criteria," Weber said. Launch criteria for Artemis rockets require them to be kept within certain temperature and pressure limits; outside those limits the rockets won't fire.
The WDR intended to test 128 functions, only 13 of which weren't accomplished. Most of those functions were verified in previous tests.
We're go for August
The Space Launch System and Orion will head back to the Vehicle Assembly Building at Kennedy Space Center next week for repairs and launch preparations, which NASA said are proceeding as planned. "NASA will set a specific target launch date after replacing hardware associated with the leak," the space agency said.
At the press conference NASA said a "late August" launch was scheduled, where hopefully the SLS will fire the uncrewed Orion astronaut capsule (and several cubesats) into orbit, and then a European Space Agency booster will take the human-delivery system to lunar orbit.
After orbiting and skimming within 60 miles of the lunar surface, the ESA rocket will boost the partially reusable Orion back to Earth for a splashdown and further testing. Artemis II is scheduled for 2024 and will take actual astronauts on a similar trip without landing on the Moon.
Cliff Lanham, senior vehicle operations manager at NASA's EGSP, said the rocket will spend six to eight weeks in the VAB, barring any problems discovered during inspections. Lanham said that the Artemis I mission should be ready for its first flight in a planned late August launch window.
"We still don't know for sure; we'll have a better idea where we stand in the next couple of weeks," Lanham said.
The Artemis project is NASA's return-to-the-Moon mission, with plans to "land the first woman and first person of color on the Moon," along with exploring more of the Moon's surface and establishing a long-term presence on the Earth satellite. It will also establish the base from which an eventual Mars mission would launch. ®