الأربعاء، 27 مايو 2020

NASA, SpaceX Gear Up for Historic Crewed Launch Today

NASA and SpaceX are just hours away from making history. After years of development and testing, SpaceX is set to become the first private spaceflight firm to carry American astronauts into space as part of NASA’s Commercial Crew Program. This is also the first crewed launch from US soil since the retirement of the Space Shuttle, a long-overdue step that will free NASA from reliance on Russian Soyuz launches. With the big moment approaching, we chatted with former astronauts Cady Coleman and Nicole Stott, both veterans of multiple Space Shuttle launches, to see how they felt about the return of crewed spaceflight to the US. Spoiler: pretty excited. 

How We Got Here

SpaceX has moved quickly to develop the technology that makes its launch platform suitable for NASA service — it’s providing both the rocket (Falcon 9) and crew module (Dragon) for these launches. Former astronaut and retired USAF Colonel Cady Coleman says that has a lot to do with the way a private aerospace firm operates. “It’s a different world now. If you think back to the early space program, the government really was the designer. Working together [with private firms] is more necessary than it ever was because of the ability that commercial companies have. They can take bigger risks with [developing] hardware.”

SpaceX didn’t get here on its own, though. “The SpaceX team has had access all along to the lessons learned from NASA’s other programs,” says former astronaut Nicole Stott. “That’s a real advantage when going into a new project. When we have public-private partnerships, we can avoid re-learning the same lessons.”

Today’s launch is primarily about the Crew Dragon capsule, sometimes called Dragon 2. This is the same type of spacecraft that SpaceX used in last year’s uncrewed Demo Mission-1. Unfortunately, that craft exploded when it was undergoing testing back on Earth. SpaceX and NASA had to push back the launch timeline, but all systems are go just a year later. That might seem fast to an outside observer, but both Coleman and Stott expressed great confidence in the way NASA and its commercial crew partners have worked together. “We’ve always had a ‘here’s how we can’ not ‘here’s why we can’t’ approach,” says Coleman. 

The launch

Today’s launch, known as Demo Mission 2 (DM-2), will take place on the historic launch pad 39A at Kennedy Space Center. SpaceX is using a Falcon 9 Block 5 design, the same rocket the company uses for cargo missions on a regular basis. This core in particular (B1058) has never been launched before, but SpaceX will try to land it on its drone ship after it detaches from the Dragon.

If all goes to plan, the Falcon 9 carrying astronauts Doug Hurley and Bob Behnken will leave the launchpad at 4:33 PM EDT. This launch will differ from past crewed missions in several ways, and it took time for SpaceX and NASA to come together on the details. “In getting ready for launch, there are some things that are just a given,” says Coleman. “NASA has done this and that forever, but SpaceX says ‘we’re not doing it that way.’ And some of that is maybe not well-thought-out, and some of that is actually a really good new idea.”

Unlike previous NASA crewed launches, SpaceX will fuel the Falcon 9 after Hurley and Behnken board the spacecraft. The launch and approach to the ISS will be automated like the Demo-1 mission last year, but Hurley and Behnken will still have the option to manually control the capsule. According to Nicole Stott, that wasn’t SpaceX’s intention at the outset.

“For a long time, SpaceX as a company thought they wouldn’t need those manual backups anymore — you know, we can do everything redundantly with the electronics in the spacecraft,” she said. “Maybe at some point we’ll get there, but I think when there are humans in the spacecraft, we’re looking for that manual backup.”

Robert Behnken (left) and Douglas Hurley (right)

While the Dragon 2 has superficial similarities to the older capsule-based spacecraft like the Apollo command module and Soyuz, it’s a much more futuristic design. Nicole Stott describes it as having a “new car feel” with a “simple elegance.” Stott says the Space Shuttle cockpit had displays, switches, and circuit breakers almost surrounding the crew. By comparison, the Dragon 2 has a few large touchscreens and compact manual controls. 

After reaching orbit, Hurley and Behnken will be able to remove their restraints and float around the capsule. As this is a demo mission, NASA will most likely have an array of tasks for the crew to complete as they monitor the Dragon’s performance. Just like the ascent, rendezvous and docking will be controlled autonomously by the Dragon. After a brief stay aboard the ISS, Hurley and Behnken will return to Earth in the Dragon. 

The Crew Dragon should splash down in the Atlantic Ocean with parachutes, which SpaceX tested one final time early this month. The Dragon capsule technically has the ability to land propulsively with its SuperDraco engines, which also power the launch abort system. However, NASA opted for the tried-and-true parachute option. That’s not to say SpaceX will never have a chance to use those engines for landing.

“I think we’re going to continue looking at [propulsive landings] as an option,” says Stott. “When you get into reduced gravity environments like landing on the moon or on Mars, we’ve done that in the past. I think we’re looking at what makes the most sense with the time we have available.” Essentially, NASA needs a reliable US spacecraft now, and we know parachutes work. 

The future

After the completion of DM-2, the Crew Dragon will be ready to ferry astronauts to and from the ISS on a regular basis. Of course, that assumes everything goes well. Spaceflight is dangerous, even more so when it’s a new spacecraft. Both SpaceX and NASA have maintained a positive outlook — NASA actually chose to publicize the overall Loss Of Crew (LOC) risk of 1 in 276. Prior to the first Space Shuttle launch, the agency’s engineers estimated the LOC as at least 1 in 500. After reviewing real mission data, they said it was probably closer to 1 in 12. By the end of the Shuttle program, it was 1 in 90. 

We can only hope that the mission is a complete success and these launches become non-events — astronauts just hop on their space bus and commute to the ISS. But today, Hurley and Behnken are making history. Nicole Stott put it succinctly, saying, “They’re setting off a new era of getting back into space from the US, helping us expand what we do with all our partners in space. And as always, with the goal of improving life here on Earth.”

This historic launch will take place at 4:33 PM EDT today with live streams from both NASA and SpaceX. National Geographic and ABC News will also have two hours of live coverage starting at 3 PM EDT today on “Launch America: Mission to Space,” featuring Cady Coleman among others. In the event of bad weather, NASA has another launch window set for May 30th.

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