Alien worlds that look like eyeballs orbit small, faint stars known as red dwarf stars. Researchers are currently proposing experiments to simulate these distant, eyeball-looking planets.
Further examination may demonstrate the planets' capabilities to support life. The red dwarf stars that make up as much as 70 percent of the stars are 50 times dimmer than the Sun and approximately one-fifth as large as the Sun. NASA's Kepler Space Observatory found that half of these red dwarf stars host planets that are half of, or up to four times the Earth's mass.
Planets that have water are usually the main focus for scientists in looking for alien life. On Earth, where there is water, there is life, and researchers theorize that the same must be true for other planets. Researchers concentrate on a star's habitable areas surrounding the star. These would be areas that are not too hot or too cold and have the right temperature for water to exist on the planet.
Habitable areas of red dwarfs tend to be closer than the distance at which planet Mercury orbits the sun, due to the stars' cool temperature. Extroplanets orbit fast and often and when a planet orbits a star closely, it can become tidally locked with it because of gravitational pull.
"This means that they always show the same side to their star, just as our moon does to the Earth, which means they have one permanent day and one permanent night side," Daniel Angerhausen, an astronomer and astrobiologist at Rensselaer Polytechnic Institute, Troy, N.Y., said.
As Astrobiology Magazine reports, the night side of the planet would be icy and frozen, and the day side would have a huge ocean of water being warmed by the planet's star. This concept of permanent day and night would make the planet resemble an eyeball.
"These planets — water, eyeball or snowball — will most probably be the first habitable planets we will find and be able to characterize remotely. That's why it is so important to study them now," Angerhausen said.
To see if planets have these eyeball type of configurations, astronomers use current telescopes like the James Web Telescope. Angerhausen explained that next-generation telescopes will help to detect life, what scientists call "biomarkers." A space-based telescope called the Terrestrial Planet Finder will be constructed in the future. Ground-based telescopes of the 30-meter class range are currently being built.