Over the past year, SpaceX’s Falcon 9 missions have become major online spectacles, mostly because each launch has been followed by an attempt to land the rocket after takeoff. But the landing part of the show will be missing from SpaceX’s next launch, scheduled for January 30th. This mission will be an expendable one, according to a tweet from CEO Elon Musk, meaning the company won’t attempt to land the Falcon 9 post-launch.
It’s the first time in a while that SpaceX hasn’t tried a landing. The company has been attempting these “experimental” rocket landings since the start of 2015, and they’re becoming more and more routine. Ever since SpaceX landed its first rocket at the end of December 2015, every single one of the company’s Falcon 9 launches has been followed by an attempt to land the vehicle — either on a floating drone ship at sea or on a ground-based landing zone. And of those 10 attempts, seven have landed successfully.
But SpaceX is foregoing the landing attempt this time around because of the parameters of its next launch. The upcoming mission is tasked with sending a communications satellite, called EchoStar 23, into a super high orbit called geostationary transfer orbit. It’s a highly elliptical path that’s more than 22,000 miles above the Earth’s surface, and getting a satellite to such an altitude requires a lot of speed, which eats up a lot of propellant during launch. On top of that, EchoStar 23 is a pretty heavy satellite, weighing in at more than 12,000 pounds. Heavy satellites need more propellant to get to orbit, so getting such a massive device to such a high altitude is going to use up a lot of the Falcon 9’s supplies.
@gdoehne Expendable. Future flights will go on Falcon Heavy or the upgraded Falcon 9.— Elon Musk (@elonmusk) January 21, 2017
That means there won’t be a lot of propellant leftover to do a landing. The propellant that isn’t used during the initial launch is used to reignite the Falcon 9’s engines after takeoff, helping the vehicle to descend in a controlled way from space and touch down upright on a flat surface. Different types of launches use up different amounts of propellant during the Falcon 9’s ascent, which is why SpaceX alternates between drone ship landings and ground landings. Drone ship landings require less fuel to pull off than ground landings (we explain why here), so SpaceX often lands at sea when a rocket has to launch something heavy or go to a high orbit. For the EchoStar 23, there just won’t be enough propellant to either kind of landing.
That may change soon, though, as SpaceX is working on another version of its Falcon 9 rocket that will further emphasize reusability, Musk said. SpaceX has been flying a variant of its rocket called the Falcon 9 Full Thrust, which utilizes a super-chilled liquid oxygen propellant that helps with reusability. The super cold temperatures make the liquid oxygen extra dense, so more of the propellant can fit inside the propellant tank. That means more propellant for launch and landing.
SpaceX is also working on another upgrade to the Falcon 9 called the Block 5, which will be the final upgrade of the Falcon architecture, Musk said. In a Reddit AMA three months ago, the CEO claims this version has many improvements, including even more thrust capabilities and better legs to help with landing. “Falcon 9 Block 5 -- the final version in the series -- is the one that has the most performance and is designed for easy reuse,” Musk wrote. He anticipates that Block 5 will fly for the first time at the end of this year, so flights similar to the EchoStar 23 launch may be recoverable with this type of rocket.
Musk also said that future flights could also go on the Falcon Heavy, which still hasn’t flown yet. That rocket variant — essentially three Falcon 9 cores strapped together — was supposed to fly for the first time by the end of last year, but the Falcon 9 accident in September forced SpaceX to push back the Falcon Heavy’s launch to 2017. An exact date, though, hasn’t been announced.
Meanwhile, SpaceX has yet to fly one of its landed rockets, but the company is aiming to reuse one of these reusable rockets soon. SpaceX plans to launch the SES-10 satellite on a Falcon 9 that landed in April 2016 — the first time that one of the company’s rockets will fly again. That launch is tentatively planned for February 22nd, according to an SES representative speaking to Spaceflight Now.