Two NASA astronauts have been stranded in space for months due to an error with their Boeing spacecraft – but their return to Earth could be even scarier.
Sunita Williams and Butch Wilmore were only supposed to be on the International Space Station for eight days when they launched aboard the Boeing Starliner on June 5.
But a fault with the capsule’s thrusters – critical to propel the craft through space – means they’ve been stuck there for more than two months, and NASA says they can’t return until February next year.
The space agency is now deciding whether to stick with the faulty Starliner or launch a rescue mission using rival SpaceX’s craft, which would be a huge embarrassment for Boeing.
Rudy Ridolfi, a former Space Systems Commander in the US military, explained three scary scenarios that could have happened if he chose to join his ex, including a worst-case scenario that would see the crew burning up in the capsule on re-entry.
If NASA chooses to use the Starliner, Sunita Williams and Butch Wilmore could evaporate upon re-entry into Earth orbit or get stuck floating in space.
The Starliner problem lies in the service module, which is like the control center for the entire ship, containing the systems that control the thrusters, power, as well as water and oxygen for the occupants.
The module, located at the bottom of the capsule, is also important for aligning the craft for re-entry before launch before re-entry.
The service module must place the capsule at an angular altitude in order to re-enter Earth.
If the angle is not there, the ship will bounce out of the atmosphere, and NASA can try to find it in orbit.
If the angle is too steep, there is more friction and a greater chance of burning up in the atmosphere, vaporizing the occupants.
It’s too shallow, and spacecraft can bounce off the atmosphere and be thrown back into space like rocks in a pond.
“As long as the capsule is lined up correctly for re-entry, everything will be fine,” Ridolfi said.
‘(If the capsules don’t line up) they either burn up or bounce back into space.’
“If the Starliner Service Module places the capsule in the re-entry window, then the capsule’s ablative heat shield will fail,” Ridolfi added.
Five thrusters failed during the 24-hour journey that carried two astronauts to the ISS in June.
One of the main concerns is that more thrusters could fail on the return leg, leaving them floating in limbo, somewhere between the ISS and Earth.
Based on the amount of oxygen and power capabilities the Starliner has, the crew will have about 96 hours to save the thrusters and return to Earth.
Suni Williams and Butch Wilmore were only supposed to be on the International Space Station for eight days when they launched aboard the Boeing Starliner on June 5.
The space agency is now deciding whether to stick with the faulty Starliner or launch a rescue mission using rival SpaceX’s craft.
They had to figure out which thrusters were out of order in hopes of shutting them down and still having enough power to spend a few hours getting home.
It is possible for the craft to reach Earth even in this scenario, Ridolfi explained, if the thrusters and helium leaks are not fixed, but the service module should work perfectly.
But in a worst-case scenario, NASA could be forced to send a rescue ship to Starliner to pick up the astronauts.
A space docking mission, while possible, has only been done once in human history and to save an unmanned ship.
In 1966, Gemini VIII was launched with astronauts Neil Armstrong and David Scott to perform the first docking. with Agena’s target vehicle.
‘NASA knows how to do this, but it just takes time,’ Ridolfi said.
‘If the Starliner bounced out of the atmosphere, they had to find it. You can get a general guess where it is, but you have to start taking radar, optical observations and calculate the current orbit.
‘So it might take about 180 minutes, say three hours.’
The feat will be accomplished by attaching a tunnel-like structure that will be attached to the Starliner hatch, so that it can be opened without harming the astronauts.
However, Ridolfi said that once the Starliner is in place, NASA will need to train another team of astronauts to perform space docking missions.
NASA has discussed the idea of ​​a Starliner program to return to Earth unnamed, using autonomous technology, which Ridolfi says is more likely to happen.
While the scenario is possible, Ridolfi noted that he believes NASA will choose SpaceX to carry out the rescue mission.
The Crew Dragon capsule will likely launch with two astronauts in September, allowing two seats for Williams and Willmore.
However, this means that two Russian astronauts will be launched.
NASA has been claiming for months that the Starliner is safe and that the astronauts are not stranded, which has been repeated by several media outlets.
The space agency changed its tune on Wednesday, admitting that the damaged Boeing plane may not survive on Earth again.
The announcement is another embarrassing blow for beleaguered Boeing, which has been dealing with a series of problems plaguing its commercial jets.
Problems with Boeing’s commercial jets, including turbulence, mechanical problems and tail strikes, cost the company at least $3 billion.
And NASA awarded Boeing a $4.2 billion contract to build the Starliner as a taxi for astronauts to the ISS.
A meeting this week of NASA’s Commercial Crew Program, which oversees Starliner, ended with some officials disagreeing over plans to receive Boeing’s test data and use Starliner to bring astronauts home.
“We don’t poll in a way that leads to conclusions,” said Commercial Crew Program chairman Steve Stich.
“We heard from a lot of people who were concerned, and the decision was unclear,” said Ken Bowersox, NASA’s chief of space operations.
Tuesday marked the 60th day the Starliner crew has been in space, longer than the eight-day mission.
NASA and Boeing have been working hard to test problems in the field to determine the safety of Starliner, which has at least five helium leaks and is missing five of its 28 thrusters.
Last week Boeing said it ‘remains confident in the Starliner spacecraft and its ability to return safely with the crew.’
Boeing testing so far has shown that four Starliner jets failed in June because they overheated and automatically shut down, while another thruster fired back during tests that appeared weaker than normal due to fuel constraints.
A ground test at the end of July at the White Sands Missile Range in New Mexico has helped to reveal that overheating the thrusters caused the Teflon seals to warp, choking the propellant tubes for the thrusters and thus weakening the thrust.
“That, I would say, increases the level of discomfort, and not having a total understanding of the physics of what is happening,” said Stich, explaining why NASA now seems more willing to discuss the Crew Dragon contingency after previously downplaying the prospect. journalist.
Starliner took off on June 5 at 10:52 a.m. ET from the Cape Canaveral Space Force Station in Florida with a leak that forced a scrub in May.
The team detects a helium leak valve and clears the mission.
NASA and Boeing have been working hard to test problems in the field to determine the safety of Starliner, which has at least five helium leaks and is missing five of its 28 thrusters. Butch Wilmore and Suni Williams have been in space for more than 60 days
Engineers suspected that the issue came from a broken rubber seal the size of a shirt button, and said even if the leak worsens, it can be managed on the plane – and set the next launch to June 1.
However, Starliner again suffered an accident when the capsule was automatically stopped minutes before launch by the computer-abort system. exit.’
The Starliner has experienced five failures of its 28 maneuvering thrusters, five leaks of the helium gas intended to propel the thrusters, and a slow-moving propellant valve that marks a past problem that has not been resolved since launch.
When the Starliner came close to the space station for docking on June 6, five thrusters failed to prevent the spacecraft’s close approach until Boeing made repairs.
Over the past few weeks, Boeing has been conducting thruster test firings on the ground and in space to understand why five thrusters failed before the Starliner arrived at the space station.
All but one are back online. Helium leaks in the capsule’s propulsion system were also cut.
