The US space agency says it will try to launch its new Moon rocket on Saturday.
A take-off attempt on Monday had to be canceled when one of the vehicle’s four engines would not cool to the required operating temperature.
After reviewing the data, the engineers believe they now understand why the problem occurred.
They think it’s likely related to an inaccurate sensor reading and that they can develop a strategy to address the issue on launch day.
This involves starting the cooling process of the motors at the start of the countdown.
“We have a path forward to get where we need to go, to support the next launch,” said John Honeycutt, who manages the Space Launch System (SLS) rocket project at NASA.
The launch on Saturday will be scheduled for 2:17 pm local time (6:17 pm GMT; 7:17 pm BST) at Kennedy Space Center in Florida.
The controllers will be given two hours to get the rocket off Earth.
SLS is the largest launch vehicle ever developed by the US space agency.
It’s the modern equivalent of the Saturn V rockets that sent humans to the moon in the 1960s and 1970s, but with considerably greater thrust from the launch pad.
SLS will send a new large crew capsule called Orion on a series of missions to the moon under NASA’s Artemis program. This first mission is called Artemis I and will be an unmanned demonstration.
The reason for Monday’s scrub was not related to the engine itself (Engine number 3), but rather to the system that conditions it for flight.
The power unit must not be upset by the sudden injection of super-cold propellants; instead, it must be slowly brought to the correct operating temperature (-250 ° C) before launch by purging some liquid hydrogen from the tank of the central stage above.
On Monday, sensor readings suggested the engine was 15-20 degrees C below where it needed to be.
Engineers believe the purge system was working properly; it was just that the sensor system did not accurately reflect actual temperature conditions.
The engineering team plans to start the cooling process about 45 minutes earlier in Saturday’s countdown, hoping this will put everything on track.
“We’re going to try to launch the third (September). And, you know, going into this previous attempt, yesterday’s attempt, we said that if we couldn’t thermally condition the engines we wouldn’t launch, and that’s the same posture we’re going to go into on Saturday. “said Mike Sarafin, head of NASA’s Artemis mission.
The weather forecast for Saturday is not brilliant. There is currently a 60% chance that controllers will encounter a violation of their launch criteria, mainly downpours. The SLS cannot take off in the rain.
But weather officer Mark Berger struck a positive note.
“We have two hours to work with. The showers tend to have some space between them, so I still think we have a good weather opportunity for the launch on Saturday,” he told reporters.
The purpose of the next 42-day mission is to send Orion around the back of the Moon before taking him home for a splashdown in the Pacific Ocean off California.
One of the main objectives of test combat is to verify that the heat shield on the capsule can survive the heat of re-entering Earth’s atmosphere.
NASA says it will return to the moon as part of a stepping stone to learn how to get to Mars. But the researchers say there are also outstanding questions about the Moon, scientifically. There is more we need to understand about the lunar origins and, by extension, about the formation and early evolution of the Earth.
Future Artemis missions will target the lunar South Pole, where permanently shadowed craters contain ice reserves.
“Artemis is a series of increasingly complex missions, to explore the Moon in preparation for missions to Mars. When we go to Mars, the more we can learn what resources we have at our disposal and how to use them, the better prepared we are,” he said. NASA chief scientist Kate Calvin told BBC News.