- zshaul
Starlink L20 by the Numbers

March 11th, 3:13 AM Est atop a Falcon 9 booster from SLC-40 at Canaveral Space Force Station
It’s all about the numbers this launch, lots of numbers. With these latest sixty satellites now in their respective orbits it brings our grand total to 1265 satellites launched, with 1140 still in orbit since their initial batch of sixty launching back in 2019. Flying tonight’s mission is booster 1058, that’s right the NASA “Worm” logo booster, becoming the fourth SpaceX Falcon 9 booster to launch six time. It was first used back with the DM-2 mission that launched astronauts Bob Behnken and Doug Hurly to the ISS (International Space Station) in May of 2020. It then went on to launch the ANASIS-II mission in July of that same year before bringing Starlink L12 to orbit in October, 2020. Next up it made history being the first time NASA would use a previously flown booster for a CRS (Commercial Resupply Services) mission in December, also 2020. Lastly it flew the Transporter-1 mission where one-hundred-forty-three satellites were sent to orbit in January of 2021.

Starlink L20 will be the 110th launch of a Falcon 9 rocket, and the 56th re-flight of a Falcon 9 rocket. Also the 52nd flight of a flight proven booster (meaning the booster survived the mission) It’s the seventh flight of the year for SpaceX and the 76th booster landing overall. It comes as the 66th launch from SLC-40 and the first ever launch on March 10th UTC for the company. This will be the 19th landing on the drone ship “Just Read The Instructions” which is fitting since it’s also the 19th orbital attempt from any launch provider this year so far. Are you staying with us? I said it was all about the numbers, but we are almost through. Tonight’s mission marks the fastest turn around time between the fifth and six launch of the same booster at forty-five days, and the first reflight of a fairing half recovered by the vessel GO Quest. Lastly it’s the fastest and second fastest turn around time of any fairings ever used with tonight’s being last flown just 87, and 109 days previously. Oh one last thing, even though this is the fifth launch of Starlink’s this year it’s technically the sixth batch to make orbit in 2021 as SpaceX put ten aboard their Transporter-1 mission when another companies satellites were damaged and could not be flown.
Weather as reported by the 45th Space Wings gave us a 90% GO for launch on weather constraints with the main concerns being lift off winds, and the cumulous cloud rule. The morning had very few clouds around the launch site and this was a great time overall as the recovery area had low concerns for a landing attempt. In the day’s where SpaceX rules it can be difficult to understand why a scrub has been called when conditions seem perfect at the Cape. The drone ships sit for these missions 633km offshore where the first stage booster will land on them before being towed back to port. That’s a long ways away from the launch site, and can have very different weather. But the cost saved by the reusability of their rocket components makes the wait for perfect conditions at both the launch and landing site worth it. Speaking of reusability, there will be no attempt at catching the fairings tonight as both of the fleets recovery vessels are still in port, and missing arms that hold up the nets used to pluck the fairings out of the sky as they float back to Earth.