New Paper Says Aliens Might Slingshot Themselves Off Super-Earths

Ok, so last month, scientists posited the idea that maybe we haven’t met any aliens yet, because they live on a “Super-Earth” sized planet, and gravity there is so strong that it’s prevented them from having a successful space program. But now, a new paper has provided a solution to that problem: a slingshot.

Astrophysicist Michael Hippke, made the astute observation that it would be pretty difficult to launch a rocket from a Super-Earth sized planet, due to its high surface gravity and the extreme amount of power needed to achieve escape velocity.

This came in light of the recent discovery that Super-Earths, or rocky planets around 10 times the size of Earth, are the most common planets in solar systems we’ve observed so far. In fact, scientists believe they’ve just recently discovered one in our own solar system.

These planets would also have thicker atmospheres, shielding the surface from dangerous cosmic radiation and solar activity, creating even more favorable conditions for life to flourish. In short, there’s a really good chance life exists on those planets, and we’ve pinpointed about 1,000 of them.

That’s why scientists want to study them, but if there’s an indirect observation that could rule them out, why waste time? That was the point of Hippke’s observation and it provided a relatively new answer to the Fermi Paradox; if the universe is so vast, why haven’t we made contact with or observed extraterrestrial life?

But now in a riposte to Hippke, a new paper has argued that one way of overcoming such intense gravity would be a slingshot assist to traditional rocket propulsion, otherwise referred to as a tether-assisted space launch system. With a Super-Earth planet, it would require more than double the escape velocity and about 104 times the amount of fuel required to leave Earth. But not if you only need to get half way there…

This hypothetical tether would be attached to what’s described as a “skyhook” rotating with the planet’s orbital velocity. At some point the tether attached to the hook would pause momentarily at a lower altitude, allowing a launched rocket to dock with it, before being flung into orbit. This would save a significant amount of fuel and allow the rocket to use the planet’s gravity as an assist.

This idea seems to piggyback off the concept of a space elevator, although the paper acknowledges that a Super-Earth’s gravity would pull too hard on a space elevators cables to make the idea feasible. The material needed to build a tether that strong has yet to become a reality here on Earth, but scientists working with carbon nanotubes think they may have something soon.

If these hypothetical arguments just sound like sci-fi conjecture, it’s because they are, at least for now. But they could form the basis for future innovations in rocket propulsion, interplanetary space flight, and hopefully, discovering alien life.

Alex R. Howe, the author of this recent paper seems to hint that the concept of a tether-assist could be implemented with modern technology and would be especially useful for interplanetary travel, where fuel weight is such a tricky variable. Will Elon Musk take note?