Sunita Williams won't return to Earth before 2025. Details

Sunita Williams and Butch Wilmore, the NASA astronauts stuck aboard the International Space Station for two months now, received a terrible jolt on Wednesday. As per the space agency's latest plan, the two of them are staring at a massive delay in their return trip which might not happen before February 2025.

Sunita and Butch launched into space on Boeing's Starliner, its first crewed mission, in June this year. However, the spacecraft developed several issues which NASA has been trying to fix for the longest time.

According to a contingency plan announced by NASA, a two-person crew will be launched on SpaceX's Crew-9 mission in September.

However, it won't be until months later that the crew will return. Starliner's thrusters have developed problems along with helium leaks, leading to concerns that a return trip might prove disastrous. However, Boeing is not doubting the Starliner and had earlier said that it "remains confident in the Starliner spacecraft and its ability to return safely with the crew".

The thruster issue is the main problem facing the Starliner which had issues while docking with the space station. A design flaw is causing the propulsion devices to overheat.

There are four thrusters fitted around the circumference of the rocket in propulsion pods, which NASA officials call "doghouses". These create a thermos-like insulation due to which the heat remains caught inside, causing them to overheat.

"What we have found in this flight is we have fired the thrusters more than expected, and I would say more frequently," explained Steve Stich, NASA's commercial crew programme manager.

Boeing and Starliner problems

Boeing has been marred with a host of problems owing to technical issues with its commercial aeroplanes. Boeing has also pleaded guilty to a criminal fraud conspiracy charge in its fatal 737 MAX crashes.

The two crashes in total claimed the lives of 346 people in Ethiopia as well as Indonesia more than five years ago. This, along with other turbulence and mechanical issues, has cost Boeing at least $3 billion.

WATCH:Boeing Starliner: Sunita Williams, Barry Wilmore address press over return delays

However, NASA entered a $4.2 billion contract with Boeing to build Starliner which would carry astronauts to the ISS. However, the original launch was delayed due to helium leaks in May. Later on June 1, the launch was again aborted at the last minute by a computer abort system. Starliner finally took off on June 5 from Cape Canaveral Space Force Station in Florida.