5:20pm ET Update: Fueling of the Falcon 9 rocket has begun, with a 5:47pm ET (21:47 UTC) launch time anticipated.
Original post: A Falcon 9 rocket has gone vertical on Thursday morning at Launch Complex 39A in Florida, and SpaceX is on track for the liftoff of a brand new version of its workhorse booster. The launch of the Bangabandhu Satellite-1 to geostationary transfer orbit is set for 4:12pm ET (20:12 UTC) Thursday, with a launch window that stretches for a little more than two hours.
The highlight of this flight is the debut of the Block 5 version of the Falcon 9 rocket (which Ars previewed thoroughly last week). SpaceX founder Elon Musk has said this will be the final "substantial" upgrade to the Falcon 9 rocket, optimizing the booster for reuse. The company hopes to be able to fly each Block 5 first stage 10 times before significant refurbishment is required.
Ten flights of an individual booster would be hugely significant, as SpaceX has thus far only ever reused each of its Falcon 9 rockets a single time. Additionally, the company hopes to reduce the turnaround time between launches of a Falcon 9 booster, now several months, to a matter of weeks.
Every orbital rocket since the dawn of the Space Age, except for components of the space shuttle, has been thrown away after a single flight. The versatile shuttle, which ended up costing about $1 billion per flight, never proved economical. Now, with the Block 5 version of its rocket, SpaceX finally hopes to close the loop by building a rocket with a short turnaround and flying it multiple times at a relatively low cost.
The first step toward that goal begins today. Weather conditions are forecast to be 80 percent go. A landing attempt will occur at 8 minutes and 10 seconds after launch, aboard the Of Course I Still Love You droneship. The webcast below should begin about 15 minutes before the launch attempt.
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Ars Technica
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