The successes and mistakes in the history of SpaceX 3:20
(CNN Business) - NASA astronauts Robert Behnken and Douglas Hurley, the first to travel into orbit aboard a spacecraft developed by a private company, are aiming to return to Earth this weekend, if the An approaching hurricane does not delay those plans.
These men have been aboard the International Space Station for two months, after departing from the Kennedy Space Center in Florida in SpaceX's Crew Dragon capsule.
Their journey began with the landmark launch in May that marked the first manned mission to take off from US soil in nearly a decade, and it could be the first of many if the capsule safely lands on the Florida coast this weekend.
- READ: SpaceX Crew Dragon took flight on a historic mission. Whats Next?
Hurley and Behnken are scheduled to board their Crew Dragon spacecraft, nicknamed Endeavor, on Saturday and leave the space station around 7:30 p.m. ET to begin their 19-hour journey home. Landing is scheduled for 2:42 pm ET on Sunday.
But all eyes are on time: Hurricane Isaias is heading for Florida, likely causing winds and high waves at all possible Crew Dragon landing sites.
Watch the progress of tropical cyclone Isaiah 9:12As of Thursday night, NASA said it still planned to move forward with the landing, but "the teams will continue to monitor the weather before undocking on Saturday night," the space agency said in a tweet.
@NASA and @SpaceX remain GO with plans to bring @Astro_Doug and @AstroBehnken home to Earth this weekend. Teams will continue to monitor weather before undocking Saturday night. Read more: https://t.co/hPa9kahsH4
- NASA Commercial Crew (@Commercial_Crew) July 31, 2020
A safe return home is crucial. Although SpaceX previously launched a Crew Dragon on an unmanned demo mission, Hurley and Behnken's mission is still considered a test. Both are veteran NASA astronauts and test pilots specifically trained to respond to any technical issues that may arise in the new vehicle, and NASA will not officially certify Crew Dragon as a human-friendly spacecraft until it makes a safe return.
And the return trip is, in some ways, even more risky than launch. Crew Dragon will need to traverse Earth's atmosphere at 17,500 miles per hour (approximately 28,000 km / h). According to NASA, rapid air compression and friction between the air and the spacecraft will heat the exterior of the spacecraft to approximately 1,900 degrees Celsius.
What's next for the collaboration between NASA and SpaceX? 1:43Behnken described his experience of re-entering the atmosphere on previous NASA missions last year: “You actually see light from the atmosphere as it heats up the outer parts of the spacecraft. You see some orange lights flickering in the plasma as it passes through the windows. "The vehicle is going through something quite strong, and we will expect it to watch over us as it takes us through the entrance," he said.
Then, as the Crew Dragon approaches Earth, it will deploy a small set of parachutes, called "braking parachutes," to begin to slow down before a large column of four parachutes unfolds to further decelerate the vehicle. If all goes well, Crew Dragon will be traveling at less than 20 miles per hour (32 km / h) when it touches the water.
"I don't think we're nervous," Hurley said from the space station during an interview with Rachel Crane of CNN Business last month. “We are fully confident that the vehicle will function as it is supposed to. That said, it is a completely different entry profile than what we are used to or used to on the Space Shuttle, "he explained.
Astronauts will experience much higher G-forces in the Crew Dragon, Hurley said. And it will mark the first time astronauts have landed in water since 1975.
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Even after landing the journey can be very hectic. The water can push the spacecraft, causing astronauts discomfort as they wait for the recovery ships to arrive.
"It takes a little time, so ... we'll both have the appropriate hardware ready in case we start to feel a little bad," Behnken said during a press conference on Friday. The hardware, the astronauts clarified, will be a paper bag very similar to the one that airlines keep in the pockets of the rear seats for passengers with nausea.
Behnken and Hurley will also need to land in a place where the weather is calm so that strong winds and high waves do not interfere with the landing and the recovery process. That means the weather criteria for landing are even stricter than for launch.
NASA and SpaceX officials will continue to monitor the forecasts until Crew Dragon re-enters the atmosphere.
Clashes with Mother Nature have already been a recurring theme on Hurley and Behnken's journey. Its first launch attempt in May was thwarted by electric. And during its second (successful) launch attempt on May 31, the countdown clock hit zero just as a batch of storm clouds cleared the sky.
If time prevents the Crew Dragon from decoupling this weekend, NASA and SpaceX will try again next Wednesday, August 5.
NASA and SpaceX will stream each moment of Hurley and Behnken's return trip here online.
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