A new study places limitations on aliens living on “super-Earths” being able to engage in interstellar travel. “Super-Earth” planets can reach sizes ten times the mass of our own. Their greater mass results in stronger gravitational pulls, making it exceedingly difficult for extraterrestrials to ascend into space, writes Charles Q Choi for Space.com.
Michael Hippke, an independent researcher with the Sonneberg Observatory in Germany researched the difficulty of spaceflight for inhabitants of super-Earths, or exoplanets. According to the study, to launch the equivalent of an Apollo mission, a rocket on a super-Earth would need to have a mass of about 444,000 tons, due to fuel requirements—think of the mass of the Great Pyramid of Giza in Egypt. “On more massive planets, spaceflight would be exponentially more expensive,” Hippke explains.
Scientists previously hypothesized that worlds other than Earth-like ones could offer circumstances suitable for life, possibly being even more habitable because their stronger gravitational pulls would hold thicker atmospheres, better shielding life from harmful cosmic rays. However, Hippke limits this “super-habitability” theory, calculating that the strong gravitational pull of such planets could make it more difficult for extraterrestrials to leave their home.
Hippke calculated the rocket sizes needed to escape a super-Earth 70 percent wider than our planet and 10 times more massive. On such a world, the escape velocity is about 2.4 times greater than on Earth. “Civilizations from super-Earths are much less likely to explore the stars,” Hippke concludes. He believes they would make more “use of lasers or radio telescopes for interstellar communication…” He submitted his findings to the International Journal of Astrobiology.