Super-Earths have been seen as planets that have the potential to host alien life. These types of planets are more common than Earth. There is just one problem with Super-Earths: gravity.
Stronger gravity on these planets may make it difficult for aliens to visit Earth.
Too Much Gravity
A new paper published in the International Journal of Astrobiology determines that possible alien life living on Super-Earths may have a hard time leaving the planet. Author Michael Hippke says that since the planets are heavier and larger than the Earth, they will have a higher surface gravity which would affect their ability to travel into space. The amount of fuel required for the aliens to leave their planet would be massive.
Super-Earths that have twice the radius of Earth can have a mass 10 times the size of Earth. This can make the planet have twice the gravitational pull of Earth, which would make space travel more difficult.
There is one surprising way that more gravity is beneficial, it helps with the atmosphere. This would make it easier for the planet to hold gases, making the atmosphere thicker. Having a thicker atmosphere can help shield the aliens from cosmic rays.
Researchers were able to work out how much fuel would be necessary for aliens to achieve space flight in a Super-Earth with 10 times the mass of Earth. They determined that a sizable fraction of the planet would have to be used up as fuel for the launch. This would limit the number of flights that could be sent to space.
The authors also state that if the planet is more than 10 times larger than Earth, space travel would become unrealistic.
Super-Earths
Even though Super-Earth is accompanied by the superlative "super," they're much more common than Earth. There are more Super-Earth planets than Earth-like planets. Like Earth, some Super-Earths occupy the Goldilocks zone or habitable zone away from their host star.
The first Super-Earths were discovered in 1992. Both planets are located around the pulsar PSR B1257+12 and have a mass around four times the size of Earth. In 2007, two Super-Earths located at the edge of the habitable zone were discovered around Gliese 581.
Along with a thicker atmosphere due to gravity, Super-Earths would also have flatter topography. The size would also allow the interior to retain more heat. It would also be possible for Super-Earths to have a magnetic field supported by liquid metals.