But an orbital rocket needs to fly 27000 kilometers per hour to stay in orbit.So the team added two more stages to the rocket, each with its own engine, to give it the extra speed it needed to reach orbit.The second modification was to make the rocket bigger.The SS-520-5 is nearly twice as tall as the SS-520, and it’s now wide enough to fit a satellite.
Picture a rocket shooting into space. Is it a towering beast that dwarfs nearby buildings and palm trees? Not necessarily. Rockets that go to the International Space Station and beyond are closer to the height of a rollercoaster than they are to a house. But you don’t have to be that large to get to space. Today, we’re going to celebrate the smallest rocket to ever orbit the Earth: The Japan Aerospace Exploration Agency’s SS-520-5. Launched back in 2018, its success could help usher in a new era of getting stuff where you want it in space, when you want it, but in space.
The SS-520-5 stands just 9.5 meters tall and 0.5 meters in diameter, making it small enough to hug! Meanwhile, you could try hugging the likes of NASA’s Space Launch System, or SLS, which sent the Artemis I mission around the Moon back in 2022. But it would probably feel more like you’ve just kind of smushed yourself up against the side of it. The enormous SLS is over 98 meters tall, which is over ten SS-520-5 rockets stacked on top of each other.
The difference in size all comes down to the job each is built to do. Deep space rockets like the SLS use their extreme size to pack in a bunch of fuel and the super powerful engines needed to push people and cargo into, as the name suggests, deep space. The closest relative to the SLS might be the Saturn V rocket, which took Apollo astronauts to the Moon in the late 1960s and early 1970s. And it was even larger, at 111 meters tall.
The most common rockets used today are orbital rockets. These take cargo, whether that’s satellites or astronauts, into space with enough speed for them to stay in lower orbits around the Earth. The Russian Soyuz and SpaceX Falcon 9 rockets, famous for their trips to the International Space Station, are both orbital rockets. They’re between 45 and 75 meters tall, and are about half the diameter of the SLS.
So SS-520-5 is way smaller than the SLS partly because it’s only meant to send stuff into low Earth orbit, not deep space. But at 9.5 meters tall, it’s also much smaller than typical orbital rockets. And that’s because SS-520-5 is actually a modified suborbital rocket. Suborbital rockets have enough oomph to get above the Kármán line, the arbitrary 100 kilometer height many scientists use to define the edge of space. But they don’t go fast enough to stay in orbit around Earth.
The team that built SS-520-5 was on a mission to construct the smallest, cheapest rocket that could launch a satellite into orbit, so they started with a tiny suborbital Japanese rocket called the SS-520. To get their sounding rocket into orbit, the team needed to make two major modifications. First, it needed to fly much faster than it was designed to, so they added two more stages to the rocket, each with its own engine, to give it the extra speed it needed to reach orbit. The second modification was to make the rocket bigger. The SS-520-5 is nearly twice as tall as the SS-520, and it’s now wide enough to fit a satellite. In order to achieve a 125 kilometer orbit, the SS-520-5 rocket had to fly almost five times faster than the regular SS-520. This was accomplished by adding a third set of rocket engines, as well as a reaction control system between the first and second stages. The rocket also had to make a turn at the right time in order to reach orbit.
Nestled in the nose cone of the third stage was a CubeSat, which is a tiny satellite measuring 10 cm square and weighing 1.3 kilograms. CubeSats can be used for a wide variety of tasks, including disaster response and climate monitoring.
The SS-520-5 is a great option for launching CubeSats into space, as it is much smaller and faster than larger rockets like the SLS. However, it is yet to be seen if it is financially viable.
The SS-520-5 has earned its place as the king of tiny space rockets and is our Pin of the Month for July. Show your support by ordering the pin from DFTBA.com/SciShow.