Why is SpaceX’s Starship so important?
This article in video-format (ZenothKSP)
SpaceX’s Starship is revolutionizing the spaceflight industry. But what exactly is it going to do, and why is it so important? In this article, I will tell you everything you need to know about Starship, So let's start at the first and most important reason.
Reusability
SpaceX is aiming to make Starship the first 100% rapidly reusable rocket. Nearly all currently operational rockets just dump their stages in the ocean, never to be seen again. This is a huge waste of time, money, and resources, and as in SpaceX founder and CEO Elon Musk's words, ‘it is the equivalent of flying a Boeing 747 and just throwing it away after one flight’. On SpaceX’s other rockets, Falcon 9 and Falcon Heavy, the first stages can land on a drone ship or return to the launch site to be reused. Starship can also do this with its first stage, where the giant 70-meter high booster named Super Heavy, returns to the launch site and literally gets caught by a skyscraper with giant robotic arms, named Mechazilla. These robotic arms, nicknamed Mechazilla then place Super Heavy on the launch mount, and then prepare it for reuse.
Super Heavy being caught by Mechazilla (SpaceX)
This is not that much different from the Falcon rockets. But for Starship, SpaceX also wants to reuse the 2nd stage, which the Falcon rockets can't. On its way back from orbit, the 50-meter-high Starship uses atmospheric drag to slow itself down and uses flaps to maneuver itself. It is protected from atmospheric heating by its giant heat shield, and during the final parts of reentry it enters a sort of bellyflop to maximize its drag. At around 700 meters above the ground, it will light its engines and move into a vertical position, after which it will also be caught by Mechazilla. It is then placed back on top of Super Heavy, refueled, and launched again. SpaceX is aiming to eventually launch Starship for a lower price than their first ever rocket, the Falcon 1, which went at around 7 million US dollars per launch, and Elon Musk says he wants to be launching thousands of Starships per year by 2028. This rapid increase in launch cadence will be the key foundation for the next subject.
Moon, Mars & Beyond
The main reason SpaceX was founded was to send humans to Mars. It was their goal in 2002, and it is their goal now in 2024. But why does SpaceX want to send humans to Mars? Well, one of the reasons is that in case of some sort of global catastrophe wiping out all life here on Earth, say, for example, a giant meteor or a nuclear war, having a self-sustaining colony on Mars might just be the key to saving the species, as it could be the only place where human life remains. And besides, discovery is in the DNA of humans.
Render of Starship headed to Mars (SpaceX)
Not only is SpaceX going to Mars, but they have also been contracted by NASA to send humans back to the surface of the Moon for the Artemis missions. Currently the first Artemis lunar landing is scheduled for September 2026 and SpaceX is developing a special lunar Starship variant: the Human Landing System, or Moonship. Moonship does not use any flaps or a heat shield to land, because the Moon doesn't have an atmosphere, and the crew will return to Earth on NASA’s Orion capsule. And all of this comes back to where I ended my previous point, a high launch cadence.
Starship Human Landing System on the Moon (SpaceX)
Orbital refueling
Starship will need to launch a lot in order to go to the Moon or Mars. It may be huge, but its reusability is also a limiting factor as to how far it can go. If Starship wants to go to the Moon or Mars, it will need to be refueled up to 10 times in Earth orbit before it can go, which, you guessed it, requires a high launch frequency. SpaceX wants to attempt a ship-to-ship propellant transfer as soon as 2025, where two ships will dock in Earth orbit and transfer some propellant from one ship to the other. It will be the first time a propellant transfer has been done between two vehicles in space, which will be another groundbreaking achievement.
Refueling Starships (SpaceX)
Heavy lift capability
Even when fully reusable, Starship Block 2 will be able to carry more than 100 tons into Low Earth Orbit, which is 5% more than an expendable SLS and only 30% less than an expendable Saturn V. It will be able to help build giant space stations, like Vast Space’s Starship-Class Module and their giant Artificial Gravity Station. It will launch the Starlab space station in 2028, and it will launch thousands of giant Starlink V2 satellites in the coming years. The next Polaris missions are even planned to be on Starship, which will be the first crewed Starships to ever fly, and there are dozens of proposed Low Earth Orbit Starship missions just waiting to be launched as soon as it enters operation.
Starship launching from Starbase (SpaceX)
Point-To-Point Travel
In a few decades, SpaceX wants to make Starship one of the primary sources of aerial transportation and have it be a kind of premium option for more time-sensitive flights. A flight across the world with a traditional airliner from, say, New York to Melbourne could take more than 20 hours. But with Starship, it would take less than one. It would lift off almost like any other regular launch, but instead of heading to orbit, it'll fly on a suborbital trajectory through space and then just come back down where it needs to be. And just like any current airliner, it would be fully reusable and ready to fly again in just a couple of hours. This goal is still many years down the road, but SpaceX is already kind of demonstrating this point-to-point travel on their suborbital test flights, where Starship launched from Texas and landed right on target in the middle of the Indian Ocean in just over an hour.
Starship launching from proposed oil rig (SpaceX)
Raptor engine
SpaceX’s Raptor engine is the most advanced rocket engine ever built. The Raptor runs on liquid methane and liquid oxygen and has a sea level variant and a vacuum variant. The main difference between these two is the size of the nozzle, where the vacuum variant has a bigger nozzle extension to allow for a greater expansion ratio and thus greater vacuum efficiency. The current version of Raptor, Raptor 2, has a chamber pressure of 300 bar and uses the Full-Flow Staged Combustion Cycle, where a full flow of both the fuel and oxidizers is sent into the preburners. If this sounds complicated to you, I would recommend you watch this video by Everyday Astronaut.
Full-Flow Staged Combustion Cycle (Everyday Astronaut)
The Super Heavy booster is powered by 33 sea level Raptors, which produce more than twice the thrust of the Saturn V. Starship itself uses 3 sea level Raptors and 3 vacuum Raptors. This is going to change on Starship Block 2, where it will use 6 vacuum Raptors, set to make its debut sometime in 2025. The Raptor has broken the record for the highest chamber pressure multiple times now, with Raptor 3 aiming to reach a chamber pressure of 350 bar. Raptor is the first Full-Flow Staged Combustion engine to ever fly.
All 3 Raptor Variants (SpaceX)
So, to summarize, Starship is important because of its reusability, its goals of reaching the Moon and Mars, orbital refueling, its heavy lift capability, point to point travel, and the revolutionary Raptor engine.
Special thanks to Space Sudoer for helping with the video and article.