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In science fiction we have been shown many times to characters walking normally on the surface of different extrasolar planets as if there were no variation whatsoever, such as size or atmospheric. They don’t make any great leaps to get around and their movements are not affected in the slightest. That would only be possible if these planets had a gravity of 9.8 meters above the second square (the Earth’s gravity). So, could you walk on the surface of exoplanets?
Is it really possible to walk on the surface of extrasolar planets?
The acceleration that a body undergoes on the planetary surface and the gravity on the surface depend entirely on the Mass (M) and the size or Radius (R) of the planet. According to Isaac Newton’s famous formula: a=GM/R2, where G is gravity, it is almost impossible to find gravitational values on planetary surfaces with differences in mass and radius to planet earth. Therefore, we could not move as easily.
Even our closest and most common example is the Moon, where the gravity of its surface is approximated to g/6, so the human must move in such a peculiar way that it has become so famous among the community.
So, shouldn’t we walk similarly on extrasolar planets, shouldn’t science fiction writers make their characters move with the same peculiarities?
As a matter of fact, no.
Earth-like gravities on extrasolar planets?
According to different sources and studies, it has been possible to find planets that, despite having significant differences in radius and mass with the planet Earth (and other extrasolar planets), a large number of these worlds have gravitational properties too similar to those of the Earth’s surface.
Could we walk on the extrasolar planets? How true can it be!
How is this possible? There’s not the remotest explanation. Scientists at the Astronomical Observatory in Valencia, Spain, have commented that not only do the properties that form the extrasolar planets not explain nothing, they should not even be able to contemplate a similar gravity.
Is Newton’s formula wrong, or is there something we don’t take into account? We don’t know, but the reality is that; strange as it may seem, the creators of science fiction films were not wrong and, inexplicable as it may be, we can walk on the surface of unknown planets.