Polaris Dawn

Polaris Dawn is a planned private human spaceflight mission, operated by SpaceX on behalf of Shift4 Payments CEO Jared Isaacman, The flight will be using a Crew Dragon capsule, and is the first of three planned missions in the Polaris program. It is scheduled to launch no earlier than 31 July 2024 at 05:30 UTC.

History
The Polaris program was announced by Jared Isaacman in February 2022, five months after the first all-private astronaut mission, Inspiration4, which was also financially backed by Isaacman. Development of several technologies necessary for the mission is also part of the program, including extravehicular activity (EVA) spacesuits for private astronauts, intersatellite laser communication links between the Dragon spacecraft and the Starlink constellation, and some accommodation for the lack of an airlock in the legacy Dragon capsule design.

Originally slated to fly as early as late 2022, the program suffered delays over the design of the EVA spacesuits and technical problems with SpaceX testing intersatellite laser communication links. By October 2022, the launch had already slipped to March 2023, and by February 2023, had slipped to no earlier than mid-2023. By mid-2023, the planned date had slipped to sometime in 2024, with Isaacman confirming in December a launch date of April 2024. On June 7, in an interview, Isaacman announced that the launch was scheduled to launch no earlier than July 12, 2024.

Mission
Polaris Dawn will be a human spaceflight to orbit Earth with only private citizens on board. The crew will consist of Jared Isaacman, Scott Poteet, Sarah Gillis, and Anna Menon, who will spend up to five days in orbit. Mission plans include reaching an orbit higher than any previous Dragon mission and ultimately the highest Earth orbit ever flown by a crewed spacecraft with an initial apogee of 1,400 km, breaking the record set by Gemini 11. The crew will orbit through parts of the Van Allen radiation belt, conducting 38 science and research experiments to study the effects of spaceflight and space radiation on human health.

After the Dragon has modified its orbit down to an apogee of 700 km, Jared Isaacman and Sarah Gillis will also attempt the first commercial EVA for around two hours with SpaceX-designed EVA spacesuits, which were first unveiled in May 2024. The EVA suits will operate with pure oxygen at a pressure of 5.1 psia (35.2 kPa; 263.7 Torr), and are designed to be used for both intravehicular and extravehicular activities, removing the need for the usual IVA suits used during crewed missions. During the spacewalk, a camera and a heads-up display (HUD) will be used to provide information on suit metrics. Flame-resistant stretch fabric material, and joints which stay soft until pressurized will help to provide greater mobility, while boots will be constructed from the thermal material used on Falcon 9's interstage and Dragon's trunk. Suit upgrades from the IVA suits also include improved thermal management, and an upgraded helmet with an exterior coating that provides thermal insulation and anti-fog treatment. An umbilical will provide life support for these suits, which resemble early Gemini suits, as opposed to the more advanced EMUs used on the ISS.

Modifications will be made to the capsule's interior to withstand the vacuum, since the craft doesn't have an airlock and will be completely depressurized during the EVA. This mission will break the record for the most people in the vacuum of space at once. Two crew members will be in the depressurized craft, and the other two will be on EVA. A device called the "skywalker" will replace the cupola window used on previous mission Inspiration4. It will be located at the front hatch and will have a ladder interface to assist in astronaut egress. There are also a variety of experiments onboard with purposes varying from the study of decompression sickness (known as "the bends") to the study of spaceflight associated neuro-ocular syndrome (SANS).

This mission will be the first crewed operational test of Dragon laser interlink communication via Starlink. If successful, it would potentially decrease communication latency and increase data bandwidth for human spaceflight.

Launch
As of July 3, 2024, Polaris Dawn is scheduled to launch no earlier than July 31, 2024.