What does it take to put a satellite into space?

Well, that depends.

Most satellites that are currently orbiting earth are doing so in low Earth orbit (LEO), which is an altitude between about 100 and 1200 miles. 

Reaching these altitudes requires complicated rockets and an immense amount of fuel.

In fact, well over 90% of takeoff weight (including the rocket, payload, tanks, etc.) is made up of rocket fuel.

The dilemma of how fuel-inefficient it is to launch objects into space is known as “The Rocket Equation”. Basically, it’s that as you add weight to a rocket, it requires more fuel, but that fuel adds more weight, which now requires more fuel, which adds more weight…

And so on…

If the earth were 50% larger, we could not launch a rocket into space, since the fuel would weigh more than what it would be able to propel.

The Falcon 9 rocket uses roughly 147,000 kg of RP-1 rocket fuel and 341,000 kg of liquid oxygen during its launches.

So, you may be wondering…

Why don’t we just throw satellites up there?

Actually, you probably weren’t wondering that. Neither was I.

But the spaceflight technology development company SpinLaunch Inc was.

They are developing a “space catapult” that will be able to get a satellite into the stratosphere (and beyond) using almost entirely centrifugal force.

Using their centrifugal mass accelerator (think of a giant slingshot), they will be able to launch a satellite almost 50 miles into our atmosphere before rockets need to even begin using their fuel.

The savings, according to SpinLaunch, would be enormous. Putting a satellite into low-Earth orbit would cost $250,000, which is a fraction of the cost of current traditional launches.

CEO Jonathan Yaney claims that up to 2,000 launches could be performed a year because of the reusable launching mechanisms.

If successful, the benefits of SpinLaunch’s space catapult would be enormous, not even considering the obvious ecological impact.

Thrown For A Loop

So what are the obstacles that stand in the way of throwing 10 tons of metal at 5,000 miles per hour into Earth’s orbit?

Most significantly, reaching Mach 6 with a mechanism that needs to be reused can not be done outside of a vacuum, as air resistance would quickly burn up or rip apart…well, just about anything not protected by several inches of protective plating.

SpinLaunch’s carbon fiber tether will need to hold the 20,000 pound aeroshell at approximately 10,000 G’s before launch.

Inside its vacuum chamber that’s nearly 300 feet in diameter, when the tether reaches its full speed of 450 rotations per minute it will be holding onto the equivalent of 100,000 metric tons.

So, all they need is the world’s strongest tensile structure to hold the aeroshell containing the miniaturized rocket system and payload in a vacuum enclosed slingshot traveling six times the speed of sound?

Well, at those speeds, the molecules within the metals will become gaseous and constantly compromise the integrity of the vacuum. So a multi-step filter is needed to remove these molecules and make sure they cannot return to the chamber.

Additionally, as you probably have considered, it is impossible to “throw” an object out of a completely enclosed chamber. Creating an opening, even momentarily, would introduce enough air to the vacuum to make SpinLaunch’s space catapult a one-time use launcher.

Which would be significantly less efficient than even the burdensome Rocket Equation.

A perfectly timed airlock system is required. Opening and closing sets of doors at precisely the right millisecond in order to let the projectile through, without completely destroying the tether.

It’s just that simple…

SpinLaunch completed its first test flight in October of 2021. 

Since then, they have completed nine more suborbital launches and received $71 million from backers, which include ATW Partners and Alphabet Inc.

The final full-scale space catapult is expected to be completed and in use by 2026.

What do you think? Does it sound physically possible to be able to throw a satellite into space? Do you think this would be a widely used method if successful? Share your thoughts on this, or anything at feedback@technologyprofits.com.