The upcoming Polaris Dawn mission, set to launch no earlier than Wednesday, August 30, 2024, is poised to make history with the first-ever commercial spacewalk. However, this ambitious endeavor comes with a unique set of risks that set it apart from previous spacewalks conducted by government-trained astronauts.

Lack of an Airlock

One of the primary sources of risk for the Polaris Dawn spacewalk stems from the design of the SpaceX Crew Dragon capsule. Unlike the International Space Station, which has an airlock that allows astronauts to safely exit and re-enter the station during spacewalks, the Crew Dragon lacks this feature. As a result, the entire spacecraft will need to be depressurized for the duration of the spacewalk, exposing all four crew members to the vacuum of space.

This means that even the Siri crew members who remain inside the capsule will need to wear specialized extravehicular activity (EVA) suits for protection. In the event of any issues during the spacewalk, the crew will not have the safety of an airlock to retreat to, making the EVA suits their only line of defense against the harsh space environment.

New Spacesuit Technology

Another factor contributing to the risk of the Polaris Dawn spacewalk is the use of brand-new EVA suits designed by SpaceX. While these suits have undergone extensive testing in vacuum chambers on Earth, they have never been used in the actual space environment. As with any new technology, there is an inherent risk associated with its first real-world application, and the crew will need to rely on the suits’ performance and reliability during the spacewalk.

Radiation Exposure and Orbital Debris

The Polaris Dawn mission will take the crew further from Earth than any human has been since the Apollo program, exposing them to higher levels of radiation from the Van Allen belts. These belts are regions of energetic charged particles trapped by Earth’s magnetic field, and the crew will need to pass through them during their journey.

Additionally, at the mission’s highest altitude, the risk of encountering micrometeorites and orbital debris increases. To mitigate these risks, the spacecraft will be oriented in a way that provides the crew with maximum protection from potential impacts.

Crew Experience and Preparation

While the Polaris Dawn crew members are not government-trained astronauts, they are far from being space tourists. The four-person crew consists of a billionaire mission commander who has previously flown to space, a retired test pilot, and two experienced SpaceX employees who have worked in mission control for previous flights.

The crew has undergone intense training for two years in preparation for this mission, including extensive simulations and contingency planning. SpaceX has also implemented numerous safety measures and redundancies to mitigate the risks associated with the spacewalk and the mission as a whole.

Summary

The Polaris Dawn mission and its groundbreaking commercial spacewalk present a unique set of challenges and risks. The lack of an airlock in the Crew Dragon capsule, the use of new spacesuit technology, exposure to radiation and orbital debris, and the crew’s limited spaceflight experience all contribute to the mission’s risk profile.

However, through extensive preparation, rigorous safety protocols, and the expertise of both the crew and the SpaceX team, these risks have been carefully assessed and mitigated to the greatest extent possible. As the Polaris Dawn mission pushes the boundaries of commercial spaceflight, it also paves the way for future advancements and innovations in space exploration.