SpaceX Polaris Dawn spacewalk live: First ever private spacewalk – riskiest mission launched by a company | Science and technology news

By Thomas Moore, Science Correspondent

As previously described, Polaris Dawn Expedition Commander Jared Isaacman and one of his crew members will leave the relative safety of the SpaceX Dragon capsule more than 400 miles above Earth and spend several minutes in the vacuum atmosphere of space.

A spacewalk is considered one of the most dangerous activities an astronaut can undertake in orbit.

However, the Polaris Dawn crew will do so without the usual training, from a space capsule without a security lock while testing an experimental spacesuit.

Mr Isaacman said before the launch: “Whatever risk is involved, it is worth it.”

It is the first time since the beginning of space travel that astronauts have attempted a spacewalk without an airlock.

The two-door chamber – used on the International Space Station (ISS) and the US Space Shuttle – allows the crew to exit into space while the rest of the spacecraft remains shielded from the vacuum.

However, Dragon is too small and not designed to conduct spacewalks.

So the entire capsule – from the fittings to the computers – has been modified to be depressurized for the two-hour event. Even the two crew members who remain on board must wear full spacesuits to survive.

Mr Isaacman and his crewmate Sarah Gillis exit the capsule through a customized hatch in the nose, using handrails to guide them through the narrow opening.

They are connected to the life support systems on board via a supply tube that provides them with power, communications and pure oxygen.

Outside, they will perform a series of tasks to test a new SpaceX spacesuit, which crucially will allow full freedom of movement while protecting astronauts from extreme temperatures.

The suit itself is much slimmer than the bulky protective layers worn by NASA astronauts.