A German astronomer calculated that space launches from the surface of super-earth planets would require incredible rockets.
The number of known exoplanets is approaching 4000, most of them are gas giants, similar to Jupiter and Saturn, and only a small part are Earth-like planets, these are mostly super-earths, rocky worlds that are several times larger than ours. Possessing a large mass, they are able to retain a denser and thicker atmosphere that better protects the surface, and the vast surface itself theoretically gives more opportunities for the development of life.
But if somewhere on one of the super-earths life has developed at least to our earthly level, then that civilization must face problems unknown on Earth. Michael Hippke of the Sonneberg Observatory in Germany has calculated that due to high gravity, the development of astronautics on super-Earths can be extremely difficult, if not impossible with existing technologies. The astronomer writes about this in a short article presented in the arXiv.org online preprint library.
In fact, our launch vehicles reach 50-150 times the mass of their payload - and this is due not so much to imperfect technologies as to the fundamental features of the chemical fuel that creates jet thrust. As an example, Hippke considered the planet Kepler-20b with a mass of 9.7 Earth masses. The scientist showed that if on Earth a rocket needs about nine thousand tons of fuel to reach the second cosmic speed (required to leave orbit), then on Kepler-20b this figure reaches 55 thousand tons. The super-heavy rocket, an analogue of the earthly Saturn V, which delivered American expeditions to the moon, here will require 400 thousand tons of fuel - obviously, the volumes are hardly achievable from an engineering point of view.
Hippke also notes other difficulties that may be associated with the development of astronautics on the super-earth. Thus, it is believed that due to high gravity, such planets tend to accumulate more water and be completely covered by oceans, the surface of which is not very suitable for space launches. Unless, of course, you build a floating platform like our Sea Launch. In the end, super-Earth astronautics may well take a completely different path and start not with chemical-fueled jet engines, but, for example, with space elevators or technologies that are completely unknown to us - so far - technologies.
Yesterday Sergey Vasiliev