Their high-risk mission was supposed to last about a week — but 56 days later, two NASA astronauts are still aboard the International Space Stationwaiting as teams on the ground try to figure out how to bring them home safely in the Boeing spacecraft they took to orbit.
The besieged Starliner Capsule has two problems: its propulsion system is leaking helium and five of its thrusters malfunctioned while it was docking with the ISS. Mission managers were aware of the leaks before the vehicle took off, but said they were unlikely to affect the flight or the safety of the astronauts.
Over the weekend, NASA and Boeing engineers conducted a major test of the Starliner, which launched veteran astronauts Sunita Williams and Butch Wilmore in first manned flight of the vehicle on June 5.
The “hot fire test,” as it is known, was the second test of Starliner’s thrusters while it was docked at the space station. It involved firing 27 of the capsule’s 28 jets in bursts of no more than 1.2 seconds. Engineers on the ground evaluated the performance of the thrusters one at a time and also checked the status of the helium leaks.
On a blog post published TuesdayNASA said preliminary results were encouraging, with all thrusters tested working well.
“Both teams were very happy with the results,” said Chloe Mehring, NASA flight director for the Starliner mission. said in a statement.
The agency also said it verified that the Starliner’s propulsion system was stable and that helium leak rates had not increased in a way that could jeopardize a return trip to Earth. The helium system will be checked again before the Starliner capsule undocks from the space station, according to NASA.
Wilmore and Williams were sitting inside the Starliner capsule during the hot fire test as part of return preparations, NASA said.
Thrusters are crucial for maneuvering the spacecraft in orbit, such as when the capsule approaches the space station and when it moves away from the outpost during the undocking process.
The capsule’s reaction control thrusters are also used to guide it into the correct position before a different set of engines are fired to begin the journey out of orbit.
Starliner tests in orbit wTheme after weeks of work in the field using a test engine at NASA’s White Sands Test Facility in New Mexico. The teams subjected the engine and thrusters – which were developed for future Starliner flights – to conditions similar to those the capsule experienced on its way to the space station. Engineers also replicated the conditions Starliner will experience as it undocks and prepares to re-enter the atmosphere.
In the coming days, NASA and Boeing officials will evaluate data from all tests carried out to date and may hold a formal review to discuss when to bring the capsule and its crew of astronauts home.
NASA has not setting a target target date for the mission, but said there are opportunities throughout the month of August.
Initially, NASA set a 45-day time limit for Wilmore and Williams to remain on the space station due to constraints with the Starliner capsule’s batteries. But agency officials said earlier this month that the batteries were being recharged while the spacecraft was docked, thus decreasing the risk of extending the capsule’s time in orbit.
With this mission, Boeing hoped to prove that its Starliner capsule could safely transport astronauts to and from the International Space Station — a key step before NASA can authorize the company to conduct routine flights to the orbiting outpost. Rival company SpaceX has been transporting NASA astronauts since 2020.
Starliner’s first unmanned test flight in 2019 also encountered problems and was interrupted after software glitches prevented the capsule from attempting to dock with the space station. Subsequent fuel valve problems caused several delays before the vehicle managed to dock with the ISS unmanned in 2022.
Then, in the spring, the NASA astronaut launch postponed twice before finally taking off.
Wilmore and Williams’ long stay on the space station makes the orbiting outpost more crowded, but mission managers said there are enough supplies and resources on board to accommodate them.
While awaiting their return to Earth, Williams and Wilmore have been conducting scientific experiments and assisting with various tasks on the space station alongside the seven crew members – four NASA astronauts and three Russian cosmonauts – who were already stationed there.
“This is a tough business we’re in,” Wilmore said earlier this month at a news conference at the space station. “Human spaceflight is not easy in any regime, and there have been numerous problems with any spacecraft ever designed, and that is the nature of what we do.”
This article was originally published in NBCNews. with
