NASA’s Astronauts End Prolonged ISS Mission—Was Boeing’s Starliner to Blame?

After spending nine months aboard the International Space Station (ISS), NASA astronauts Butch Wilmore and Sunita Williams have begun their journey back to Earth aboard SpaceX’s Crew Dragon spacecraft.

The return mission, which commenced in the early hours of Tuesday, concluded with a splashdown off the Florida coast by early evening.

Prolonged Stay Due to Starliner Malfunctions

Wilmore and Williams originally arrived at the ISS in June 2024 aboard Boeing’s Starliner capsule for a mission that was initially intended to last only a few days. However, technical malfunctions rendered the Starliner unsuitable for their return, leading NASA to integrate the astronauts into a long-duration mission before scheduling their return aboard SpaceX’s Dragon capsule.

Why Crew Dragon Takes 17 Hours to Return While Soyuz Takes 3.5 Hours

Unlike Russia’s Soyuz spacecraft, which completes its return journey in just 3.5 hours, the Crew Dragon takes approximately 17 hours to return to Earth. Several factors contribute to this extended duration:

• Orbital Alignment and Earth’s Rotation: The ISS orbits Earth at 28,000 km/h (17,500 mph) at an altitude of around 420 km. A precise alignment with designated landing zones is required before descent.

• Deorbit Burn and Atmospheric Re-entry: The spacecraft performs a controlled deorbit burn for a smoother descent, unlike the Soyuz, which follows a direct ballistic trajectory.

• Heat and Parachute Deployment: Crew Dragon's re-entry is gradual to minimize stress on the spacecraft and crew, with parachutes deployed at high altitudes for a safe landing.

• Weather and Landing Conditions: SpaceX selects landing sites based on optimal weather, ocean currents, and the positioning of recovery ships. If conditions are unfavorable, the capsule may remain in orbit longer before initiating reentry.

Return Plan and Timeline

NASA’s carefully planned return operation began late Monday night (ET), with key events unfolding as follows:

• 11:05 PM (ET), Monday: The astronauts boarded the Crew Dragon capsule, sealed the hatch, donned their flight suits, and performed system checks.

• 1:05 AM (ET), Tuesday: The spacecraft autonomously undocked from the ISS.

• 5:57 PM (ET), Tuesday: The Dragon capsule is expected to splash down off the coast of Florida.

NASA has been live-streaming key moments of the mission, including the undocking sequence, deorbit burn, and splashdown procedures. Following the capsule's safe landing, recovery teams will retrieve the astronauts and transport them to Houston’s Johnson Space Center for post-mission evaluations.

Mission Significance and Future Implications

Wilmore and Williams' return marks the conclusion of an extended mission that was initially designed as a short-duration test flight for Boeing’s Starliner. However, due to propulsion system issues, NASA opted for a Crew Dragon return, underscoring the reliability of SpaceX’s spacecraft within the agency’s commercial crew program.

The mission's successful completion highlights the versatility of the Crew Dragon while raising concerns about the future of Boeing’s Starliner program, which has faced repeated delays and technical setbacks. As NASA continues its collaboration with commercial partners, the performance of both spacecraft will play a critical role in shaping the future of human spaceflight.

Also Read: Sunita Williams’ Home Village Celebrates Her Safe Return to Earth with Aarti and Prayers