ISS astronauts welcome new crew members Robert Behnken and Douglas Hurley on May 31, 2020 (Credit: NASA)

Astronauts aboard the International Space Station (ISS) are always thrilled to welcome new crew members to the orbiting laboratory. However, the May 31, 2020, arrival of NASA astronauts Robert Behnken and Douglas Hurley on SpaceX's Endeavour was particularly exciting. It was the first piloted launch from American soil since the US Space Shuttle program was retired in 2011 and the first human spaceflight performed by a public-private partnership — NASA and SpaceX.

The Crew Dragon spacecraft, which ferried the NASA astronauts to the ISS, lifted off on the Falcon 9 rocket from NASA's Kennedy Space Center in Florida at 3:22 pm EDT on May 30, 2020. Twelve minutes into the flight, the Falcon 9's reusable, first-stage booster detached and made a picture-perfect landing on an awaiting barge in the middle of the Atlantic Ocean. The rocket's second-stage booster continued to carry its payload to a stable low-Earth orbit that put the spacecraft on the right trajectory to rendezvous with the ISS, before disengaging and disintegrating in outer space.

SpaceX's Demo-2 mission launched from NASA's Kennedy Space Center on May 30, 2020 (Credit NASA)

While Behnken and Hurley, both veteran space travelers, have been on the ISS twice before, the ride this time was vastly different. Though the Crew Dragon's slick touchscreen displays allow for manual control when necessary, the spacecraft is designed to be completely autonomous with little input required from the astronauts.

The astronauts' custom-tailored black-and-white spacesuits were also very different from conventional spacesuits. Created in collaboration with Jose Fernandez, designer of superhero costumes for Batman V. Superman and The Avengers, the suits were both stylish and extremely hi-tech. "A single connection point on the suit's thigh attaches life support systems, including air and power connections," NASA said in a press release. "The helmet is custom manufactured using 3D printing technology and includes integrated valves, mechanisms for visor retraction and locking, and microphones within the helmet's structure."

SpaceX Founder and CEO Elon Musk said he wanted to create a spacesuit that inspired kids to become astronauts and want to wear the uniform themselves — to "get them fired up," he said. "Everyone should be excited that this is a thing made by humans, for humans," the visionary added.

Forty-nine minutes into the flight, Behnken and Hurley performed checks on Dragon's Draco thrusters, adjusted the spacecraft's trajectory, and began an engine burn to align orbits with the International Space Station. Once the quick tasks had been completed, the space travelers treated the millions of fans, watching the historical event from Earth, to a live-stream tour of the Crew Dragon cabin. They then settled in for the night, enjoying a gourmet meal and a few hours of well-deserved rest.

The Crew Dragon arrived at its destination early on May 31, 2020. After docking autonomously, it underwent a series of steps to connect the spacecraft to the ISS port securely. This included linking the power supply to the ISS and creating an air-locked seal between Behnken and Hurley's crew cabin and their entrance to the space station. At around 1:15 pm EDT, the Crew Dragon's occupants emerged to a cheerful welcome from NASA astronaut Christopher Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner, who have been at the ISS since April 9, 2020.

From left to right: Russian cosmonauts Anatoly Ivanishin, Ivan Vagner and NASA's Christopher Cassidy pose with new ISS arrivals Bob Behnken and Robert Hurley (Credit: NASA)

The astronauts' successful arrival accomplished two significant milestones for SpaceX — the Crew Dragon's launch and docking. The final test, bringing Behnken and Hurley back to Earth, will occur sometime in the next 110 days. If everything goes as expected — and there is no doubt it will — SpaceX will begin flying astronauts regularly to and from the ISS. The commercial spacecraft's success also brings NASA one step closer to putting astronauts back on the Moon by 2024.