Floating in space, orbiting Earth in low Earth orbit (LEO), the International Space Station (ISS) has just received NASA’s 72nd/73rd crew transport mission. The Crew-10 spacecraft, launched aboard SpaceX’s Falcon 9 rocket, successfully docked with the ISS at 9:40 AM on Sunday. The relief felt worldwide upon this docking was perhaps unparalleled in recent LEO missions.
What is Low Earth Orbit (LEO)?
LEO refers to the region of space between 100 km and 2,000 km above sea level. The lower boundary, known as the Kármán line, marks the official start of space, while the upper boundary is called the apogee. In this zone, artificial satellites and the ISS orbit the Earth. The ISS itself is situated at an altitude of about 400 km.
However, LEO is filled with space debris, making it a hazardous zone. There are around 34,000 pieces larger than 10 cm, 900,000 pieces between 1-10 cm, and a staggering 128 million fragments smaller than 1 cm. These debris pieces come from broken satellites, rocket parts, and asteroid fragments. Even a tiny piece colliding with a spacecraft could trigger a catastrophic chain reaction known as the “domino effect” or “Kessler Syndrome.”
The Crew-10 Astronauts and the Public’s Focus on Sunita Williams
The Crew-10 mission carried four astronauts: NASA’s Anne McClain and Nichole Ayers, Japan’s Takuya Onishi, and Russia’s Kirill Peskov. While the general public may not be familiar with them, the docking of Crew-10 was watched with keen interest because of the predicament of two astronauts aboard the ISS: Sunita Williams and Butch Wilmore.
Sunita Williams, though an American astronaut, holds a special place in the hearts of Indians due to her Indian heritage. Moreover, the tragic memory of Kalpana Chawla’s fatal re-entry accident still haunts space enthusiasts in India.
Why Are Sunita Williams and Butch Wilmore Still on the ISS ?
Williams and Wilmore originally traveled to the ISS aboard Boeing’s Starliner spacecraft for an eight-day test mission. However, technical malfunctions in Starliner’s thrusters and a helium leak prevented their safe return. NASA, prioritizing safety, deemed the spacecraft unfit for a crewed return. Thus, their stay aboard the ISS, meant to be brief, stretched to a long and uncertain nine months.
During this time, misinformation and political controversy brewed on Earth. Former U.S. President Donald Trump used the issue to criticize President Joe Biden, claiming that NASA had “abandoned” Sunita Williams in space. His administration fueled narratives suggesting that their return was nearly impossible, further intensifying public anxiety.
The Relief of Crew-10’s Docking
For Sunita Williams and Butch Wilmore, Crew-10’s successful docking was a beacon of hope. Having spent 287 days stranded in space, they could finally anticipate their return journey. Their joy was visible as they greeted the four new astronauts who entered the ISS from Crew Dragon. The same spacecraft will soon bring Williams and her three crewmates—NASA’s Nick Hague and Russia’s Alexander Gorbunov—back to Earth.
A Change of Command Before Departure
Sunita Williams currently holds the role of ISS commander. Before departing, she will transfer command to Russian cosmonaut Alexey Ovchinin. Despite geopolitical tensions on Earth, space remains a zone of cooperation, where national boundaries dissolve in the pursuit of science.
NASA has planned Crew Dragon’s return as a meticulously scheduled event. According to the plan, on Tuesday, at 5:57 PM local time, the spacecraft will leave the ISS and re-enter Earth’s atmosphere.
Why “Splashdown” Instead of “Landing”?
Unlike the past, when space shuttles like Columbia, Discovery, and Atlantis landed on runways, today’s spacecraft use different methods. Space shuttles were retired due to high costs and safety concerns, particularly after the tragic Challenger disaster that claimed Kalpana Chawla’s life.
Now, Boeing’s Starliner lands on solid ground with parachutes, while SpaceX’s Crew Dragon, like Elon Musk’s Starship, splashes down into the ocean. Sunita Williams and her three crewmates will land in the Pacific Ocean, near the coast of Florida.
After their “splashdown,” a recovery operation will retrieve the astronauts and bring them safely back to land.
Thus, for Sunita Williams and her team, their journey will not end with a “landing” but with a “splashdown” into the vast Pacific.