Spacewalks, or extravehicular activities (EVAs), are one of the most thrilling and challenging aspects of human space exploration. During a spacewalk, astronauts exit their spacecraft or space station to conduct scientific research, repair equipment, or test new technologies. These activities are critical for maintaining space stations, deploying satellites, and advancing our understanding of living and working in space.

This article explores the history, significance, and a list of some of the most notable spacewalks by astronauts.

A Brief History of Spacewalks

First Spacewalk:
On March 18, 1965, Soviet cosmonaut Alexei Leonov became the first person to conduct a spacewalk during the Voskhod 2 mission. Leonov floated outside the spacecraft for 12 minutes, tethered to it by a 16-foot cord. The mission was groundbreaking, though not without challenges, as Leonov faced difficulties re-entering the spacecraft due to the expansion of his spacesuit.

First American Spacewalk:
Edward H. White II became the first American astronaut to conduct a spacewalk on June 3, 1965, during NASA’s Gemini 4 mission. He spent 23 minutes outside the spacecraft, maneuvering using a hand-held propulsion device called the "zip gun."

Longest Spacewalk:
The longest single spacewalk lasted 8 hours and 56 minutes and was conducted by NASA astronauts Susan Helms and James Voss on March 11, 2001, during STS-102. The mission involved assembling and maintaining parts of the International Space Station (ISS).

Notable Spacewalks in History

Apollo 9 (March 1969):
Rusty Schweickart tested the Apollo spacesuit outside the Lunar Module, paving the way for the Moon landings.
Significance: First EVA involving the Apollo Lunar Module.

Apollo 15 (July 1971):
Astronauts conducted the first deep-space EVA to retrieve film canisters from the service module.
Significance: Demonstrated EVA feasibility in deep space.

STS-41-C (1984):
Astronauts repaired the Solar Maximum Mission satellite during a historic EVA.
Significance: Showcased the ability to repair satellites in orbit.

Hubble Space Telescope Repairs (1993–2009):
Multiple spacewalks were conducted to repair and upgrade the Hubble Space Telescope.
Significance: Enabled continued astronomical discoveries by extending the telescope's operational life.

First ISS Assembly EVA (1998):
Sergei Krikalev and Jerry Ross conducted the first spacewalk to assemble parts of the ISS.
Significance: Marked the beginning of human construction in space.

China’s First Spacewalk (2008):
Zhai Zhigang became the first Chinese astronaut to conduct a spacewalk during the Shenzhou 7 mission.
Significance: Highlighted China's growing capabilities in human spaceflight.

Spacewalks by Numbers

• Total Spacewalks: Over 250 EVAs have been conducted on the ISS alone as of 2023.
• Notable Countries: The United States, Russia (and formerly the Soviet Union), China, and other international partners have contributed to spacewalk achievements.
• Longest Total Time: Russian cosmonaut Anatoly Solovyev holds the record for the most time spent on EVAs, with over 82 hours during 16 spacewalks.

Challenges of Spacewalks

Spacewalking is physically demanding and technologically complex. Astronauts must:

• Wear bulky, pressurized suits with life-support systems.
• Navigate microgravity conditions.
• Protect themselves from temperature extremes (ranging from -250°F to 250°F in space).
• Manage the risk of micrometeoroid impacts and radiation exposure.

Future of Spacewalks

With humanity venturing further into space, spacewalks will remain a critical component of exploration. Upcoming missions to the Moon (Artemis program) and Mars will involve EVAs to establish habitats, explore surfaces, and conduct scientific experiments. The development of new-generation spacesuits and robotic support systems is set to enhance the efficiency and safety of future spacewalks.

Conclusion

Spacewalks symbolize the courage and ingenuity of astronauts and their supporting teams. From the first tentative steps into the vacuum of space to intricate repairs on the ISS, these activities demonstrate human adaptability and innovation. As space exploration advances, the legacy of these EVAs will continue to inspire and enable humanity’s journey beyond Earth.