Sunita Williams returns: National Aeronautics and Space Administration (NASA) astronauts Sunita Williams and Butch Wilmore returned to Earth, hitching a different ride home to close out a saga that began with a bungled test flight more than nine months ago. Their SpaceX capsule parachuted into the Gulf of Mexico, just hours after departing the International Space Station. A splashdown occurred off the coast of Tallahassee in the Florida Panhandle, bringing their unplanned odyssey to an end.
Within an hour, the astronauts were out of their capsule, waving and smiling at the cameras while being hustled away in reclining stretchers for routine medical checks. It all started with a flawed Boeing test flight last spring. The two expected to be gone just a week or so after launching Boeing's new Starliner crew capsule on June 5. So many problems cropped up on the way to the space station that NASA eventually sent Starliner back empty and transferred the test pilots to SpaceX, pushing their homecoming into February. Then SpaceX capsule issues added another month's delay.
Sunday's arrival of their relief crew meant Wilmore and Williams could finally leave. NASA cut them loose a little early, given the iffy weather forecast later this week. They checked out with NASA's Nick Hague and Russia's Alexander Gorbunov, who arrived in their own SpaceX capsule last fall with two empty seats reserved for the Starliner duo.
Wilmore and Williams spent 286 days in space- 278 days longer than anticipated when they launched. They circled Earth 4,576 times and travelled 121 million miles (195 million kilometers) by the time of splashdown.
The duo had arrived at the ISS aboard Boeing’s Starliner capsule in June 2024, but a series of technical malfunctions left the spacecraft unfit for their return. As a result, they were integrated into NASA’s long-duration space mission before being scheduled for a return aboard the SpaceX Dragon.
Why SpaceX's Dragon takes 17 hours to return?
Unlike Russia’s Soyuz spacecraft, which can bring astronauts back to Earth in just 3.5 hours, the SpaceX Dragon capsule takes approximately 17 hours to complete its return journey. This is due to multiple factors that prioritise the safety of the crew and also landing accuracy.
What are the factors that affect return time?
1. Orbital alignment and Earth’s rotation- The ISS orbits Earth at a speed of approximately 28,000 km per hour (17,500 mph) at an altitude of around 420 km. A return journey requires precise alignment with designated landing zones, meaning the Crew Dragon cannot initiate descent immediately after undocking.
2. Deorbit burn and atmospheric re-entry- To safely return, the spacecraft must perform a controlled deorbit burn, adjusting its trajectory toward the targeted splashdown site. Unlike the Soyuz, which follows a more direct ballistic descent, Crew Dragon's descent is carefully managed to ensure a smoother ride.
3. Heat and parachute deployment- During reentry, the capsule experiences extreme heating due to atmospheric friction, necessitating a gradual descent to avoid excessive stress on the spacecraft and crew. At high altitudes, parachutes deploy to slow the spacecraft’s descent, ensuring a safe landing.
4. Weather and landing conditions- SpaceX selects landing sites based on optimal weather conditions, ocean currents, and the positioning of recovery ships. If conditions at the primary landing site are unfavourable, the capsule may stay in orbit longer before initiating reentry.
Sunita Williams, Butch Wilmore finally return to Earth | Here is the plan and full timeline
NASA’s carefully planned return operation began late Monday night, when Wilmore and Williams boarded the Crew Dragon capsule, sealed the hatches, and began pre-departure preparations.
What are the key events in the return mission?
11:05 pm, Monday: The astronauts boarded the Crew Dragon capsule and secured the hatch. They then donned their flight suits and performed a series of system checks.
1:05 am, Tuesday: The spacecraft autonomously undocked from the ISS.5:57 pm, 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. Once the capsule safely lands, recovery teams will retrieve the astronauts and transport them to Houston’s Johnson Space Center for post-mission evaluations.
What are the future implications of this mission?
The return of Wilmore and Williams marks the conclusion of an extended mission that was initially designed as a short-duration test flight for Boeing’s Starliner capsule. However, following Starliner’s propulsion system issues, NASA deemed it too risky for a crewed return, prompting an alternative arrangement with SpaceX. The successful completion of this mission will be a testament to the versatility of the Crew Dragon spacecraft, which has become a crucial part of NASA’s commercial crew program. Additionally, it highlights the ongoing challenges faced by Boeing’s Starliner program, which has encountered repeated delays and technical failures.