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First commercial spacewalk -

On September 12, American tech billionaire Jared Isaacman became the first person to perform a commercial spacewalk, undertaken during a mission called New Dawn, launched to test a new line of spacesuits. An awestruck Isaacman gushed, "Earth sure looks like a perfect world." He joins a long list of others who have spacewalked... and taken the same risks: a spacewalk is considered one of the most dangerous activities an astronaut can do in orbit.

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First spacewalk -

Soviet cosmonaut Alexei Leonov was the first person to conduct a spacewalk, or extravehicular activity (EVA). The historic event took place on March 18, 1965, during the Voskhod 2 mission.

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Under pressure -

Leonov spent 12 minutes and nine seconds outside the spacecraft, attached to it by tether. At the end of the spacewalk, Leonov's spacesuit had inflated in the vacuum of space and he could not reenter the airlock. It was only by opening a valve to allow some of the suit's pressure to bleed off that he was able to climb back into the spacecraft. As a result of the drop in pressure, Leonov suffered decompression sickness.

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First American spacewalk -

The first American spacewalk was performed on June 3, 1965, by Ed White during the Gemini IV spaceflight. White floated free outside the spacecraft, tethered to it, for approximately 23 minutes.

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Issues with hatch locking mechanism -

White used a hand-held oxygen-propelled gun called an astronaut maneuvering unit to propel himself. After reentering the spacecraft, White and his copilot, Jim McDivitt, experienced a problem with the hatch locking mechanism. The issue was eventually resolved, but had it not been then reentry into the Earth's atmosphere would have been impossible.

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Gene Cernan -

Astronauts on the next three Gemini flights included Gene Cernan. Cernan performed the second American spacewalk, but overexertion caused by a lack of limb restraints prevented the testing of a more advanced astronaut maneuvering unit and forced the early termination of the spacewalk.

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Michael Collins -

Michael Collins performed two spacewalks as part of the Gemini 10 mission—the first person to undertake double EVA.

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Delicate operation -

Gemini 10 was tasked with carrying out an orbital rendezvous with a target docking vehicle, a delicate maneuver photographed by Collins while tethered to the spacecraft.

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Richard Gordon -

A member of the Gemini 11 mission, astronaut Richard Gordon also performed two spacewalks, one of which was especially precarious and exhausting.

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Tricky maneuver -

Working outside the spacecraft, a tethered Gordon was tasked with attaching another tether to a target vehicle in an experiment to see if fuel could be conserved by tying the two spacecraft together.

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Edwin "Buzz" Aldrin -

On November 13, 1966, Buzz Aldrin became the first astronaut to successfully work in space without tiring during Gemini XII, the last Gemini mission. Aldrin, later to garner worldwide fame as the second man on the Moon, worked outside the spacecraft for two hours and six minutes.

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Prolonged extravehicular activity -

Aldrin was actually finding out and testing new ways to work outside of a spacecraft safely and effectively. Besides a tethered spacewalk, Aldrin also completed two stand-up EVAs to demonstrate the feasibility of prolonged extravehicular activity.

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From Soyuz to Soyuz via EVA -

A spectacular first was achieved on January 16, 1969, when Soviet cosmonauts Vladimir Shatalov and Aleksei Yeliseyev successfully transferred via a spacewalk from Soyuz 5 to Soyuz 4, which were docked together. The event went largely unreported in the West, but was celebrated across the USSR.

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Skylab 2 -

In the United States, the Apollo missions saw EVA curtailed until May 26, 1973, when Charles "Pete" Conrad carried out a spacewalk to inspect damage to the manned Skylab space station, caused during its launch on May 14. Conrad, together with Joseph Kerwin and Paul J. Weitz, freed a stuck solar panel and deployed a solar heating shield. This activity constituted the first-ever EVA repairs of a spacecraft.

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Skylab 3 -

Astronauts Alan Bean, Owen Garriott, and Jack Lousma between them carried out three spacewalks during the Skylab 3 mission.

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Space sickness -

All three suffered from space sickness as they adapted to weightlessness while in orbit. EVA included the installation of a sun shield to replace the one destroyed during Skylab's launch.

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Space shuttle program -

After Skylab, no more spacewalks took place until the advent of the space shuttle program in the early 1980s. Pictured is the launch on April 12, 1981, of STS-1 Columbia, the first flight of the program.

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First woman to perform a spacewalk -

The Soviets also resumed EVAs during this period. In July 1984, Svetlana Savitskaya became the first woman to perform a spacewalk, undertaken during the Soyuz T-12 mission.

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First untethered EVA -

It was in February 1984 during STS-41-B, NASA's 10th space shuttle mission, that the most famous photograph of a spacewalk was taken, captured when astronaut Bruce McCandless II was demonstrating an extravehicular maneuvering unit to perform the first untethered EVA.

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Floating in space -

McCandless ventured farther away from the confines and safety of his ship than any astronaut before him. Appearing as if floating over the Earth, he was approaching his maximum distance from Challenger when the image was caught.

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Spacewalking world record -

Anatoly Solovyev, pictured in 1997, currently holds the world record for the number of spacewalks performed (16), and accumulated time spent spacewalking (over 82 hours).

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Spacewalk hazards -

By the 1990s, EVA was commonplace but still not without risk: there are many hazards that come with venturing out into space. These include the possibility of body fluids expanding, pushing, and reshaping internal organs, and expanding skin, a condition experienced by Alexei Leonov.

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Micrometeoroid menace -

Additionally, spacewalkers must contend with the risk of micrometeoroid impacts. These tiny extraterrestrial particles that fall on Earth can puncture pressurized vessels and spacesuits, and the results can be catastrophic.

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Psychological challenge -

As fully trained and equipped as they are, astronauts undertaking a spacewalk can also be challenged psychologically. The hostile environment and perceived isolation that a walk in space affords can play mind games with even the most experienced of spacewalkers.

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Working in weightlessness -

Working in conditions of weightlessness present a unique set of parameters. The hand-capture of the Intelsat VI satellite in 1992 during the STS-49 mission required meticulous planning and skilled judgment. It remains the only EVA to date to be performed by three astronauts.

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First American woman to walk in space -

On October 11, 1984, Kathryn Sullivan became the first American woman to perform a spacewalk. Male and female astronauts are trained to the same standard and as of 2019 43 women have performed a spacewalk, according to NASA. Sullivan is pictured right with fellow astronaut David C. Leestma working Challenger's cargo bay.

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Working outdoors -

New Zealand's Cook Strait provides a spectacular backdrop while astronauts Robert Curbeam and Christer Fuglesang maintain the International Space Station. Repair and maintenance are what most spacewalks today are carried out for.

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First British spacewalk -

European Space Agency astronaut Tim Peake was the first British astronaut to take part in a spacewalk, stepping outside the International Space Station on January 15, 2016, to assist with the replacement of a faulty sequential shunt unit on the station's solar arrays.

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First in-flight space shuttle repair -

Astronaut Steve Robinson photographs the reflection in his visor during his spacewalk to repair two protruding gap fillers in Discovery's heat shield on August 3, 2005.

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Using the Canadarm2 -

During the task, the first in-flight repair of the space shuttle, Robinson rode the Canadarm2, a remote manipulator system. The repair was completed successfully.

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A new dawn -

Today, the success of the Polaris Dawn mission represents a new era in spaceflight, the extraordinary spacewalks undertaken by the crew affirmation that EVA is as exciting—and as risky—as it's ever been.  

Sources: (NASA) (Reuters) (BBC) (New Scientist) 

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