Historic Spacewalk Achieved by Nonprofessional Astronauts on SpaceX's Polaris Dawn Mission
In a groundbreaking event for private space exploration, for the first time in history, two nonprofessional astronauts have successfully completed a spacewalk, or extravehicular activity (EVA), organized by a private company. This remarkable achievement took place during the Polaris Dawn mission, which commenced on September 10 with the launch of SpaceX's Crew Dragon spacecraft from Cape Canaveral, Florida. The mission carries four crew members, including billionaire Jared Isaacman, who has financed a significant portion of the venture.
Currently, Crew Dragon is in an elliptical orbit, reaching a minimum distance of approximately 190 kilometers from Earth and extending up to 700 kilometers. Interestingly, it has already ventured out to 1400 kilometers, marking the furthest point in space ever attained by a crewed mission in over 50 years, since NASA's Apollo program aimed at lunar exploration.
The EVA was conducted by Isaacman and SpaceX engineer Sarah Gillis, while their fellow passengers Scott Poteet, a former military pilot, and another SpaceX engineer, Anna Menon, remained inside the capsule. For their excursion outside the spacecraft, Isaacman and Gillis donned experimental suits designed by SpaceX, tailored to endure the challenges of a space environment. These suits were derived from those typically worn by astronauts traveling to the International Space Station (ISS), thanks to the commercial collaborations between SpaceX and NASA.
Unlike conventional astronaut suits, which have autonomous oxygen delivery and pressurization systems, the suits used in this EVA were tethered to the capsule through tubes and cables. This connection allowed for the transfer of oxygen, nitrogen, and energy necessary to power their instruments. After roughly 40 minutes of preparation, Isaacman and Gillis alternated their exits through a hatch on the top of Crew Dragon, spending approximately 15 to 20 minutes outside each.
The significance of this EVA extends beyond its historical value; it serves as a test to assess the reliability and integrity of SpaceX's suits for future missions. EVA preparations usually consume extended durations as astronauts must adjust to pressure conditions markedly different from those experienced inside spacecraft. In contrast, within Crew Dragon, all four crew members were isolated from the external environment as there was no airlock available to facilitate a gradual transition.
Upon proper completion of the test and sealing the EVA hatch, the pressure inside Crew Dragon was restored to ensure the right oxygen levels for the astronauts to shed their suits and continue their mission. Over the course of the mission, slight adjustments were made to the capsule’s pressure and nitrogen levels to facilitate the crew’s acclimatization, minimizing risks related to pressure compensation.
While EVAs generally pose risks, primarily focused on the suits' integrity and the astronauts' mobility, today’s activity represents a pivotal moment for private space missions. It emphasizes the growing role of commercial entities in space exploration, traditionally dominated by governmental agencies. This event is particularly noteworthy as SpaceX's suits had never before been tested in the true conditions of space.
Jared Isaacman is no stranger to space travel, having previously launched into orbit in September 2021 as part of the Inspiration4 mission, also managed by SpaceX. This mission included three nonprofessional astronauts, marking a significant departure from the traditionally governmental composition of space missions.
Although the costs associated with the Polaris Dawn mission remain undisclosed, it is estimated they amount to tens of millions of dollars, in addition to the expenses incurred for developing new technologies by SpaceX. Historically, only a limited number of astronauts from NASA and other national space agencies have performed EVAs for purposes including orbital station construction and maintenance. The complexity and expense of EVA suits have underscored the need for change—a gap that commercial enterprises like SpaceX aim to fill.
Polaris Dawn is set to last five days and will incorporate about forty on-board experiments designed to assess the physiological effects of space on the human body, paralleling research conducted on the ISS, as well as testing innovative technologies intended for potential future long-duration missions to the Moon and possibly Mars. At the mission's conclusion, Crew Dragon is scheduled to splash down off the Florida coast, where a recovery team will retrieve the capsule and its crew members. Isaacman and SpaceX plan at least two further missions, although details surrounding their timing and methodologies will largely hinge on the outcomes of this current undertaking.
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