My own little rogue world! A dream come true for science fiction fans, especially those who saw Star Trek when it was new. A planet of your own, the dream of every little boy - like Trelayne in The Squire of Goths:
Today, actual scientists are thinking of new ways to discover smaller and smaller worlds that are almost unimaginably distant.
OGLE astronomers provided the first evidence for a large population of rogue planets in the Milky Way a few years ago. However, the newly-detected planet is the smallest rogue world ever found. "Our discovery demonstrates that low-mass free-floating planets can be detected and characterized using ground-based telescopes," says Prof. Andrzej Udalski, the PI of the OGLE project.
Astronomers suspect that free-floating planets actually formed in protoplanetary disks around stars (as "ordinary" planets) and they have been ejected from their parent planetary systems after gravitational interactions with other bodies, for example, with other planets in the system. Theories of planet formation predict that the ejected planets should be typically smaller than Earth. Thus, studying free-floating planets enables us to understand the turbulent past of young planetary systems, such as the solar system.
As far as I know, the first use of the phrase "rogue planet" is found in Satan's World (1967) by Poul Anderson:
"Sunless planets are common. They are estimated to number a thousand or more times the stars. That is, nonluminous bodies, ranging in size from superjovian to asteroidal, are believed to occupy interstellar space in an amount greater by three orders of magnitude than the nuclear-reacting self-luminous bodies called stars. Nevertheless, astronomical distances are such that the probability of an object like this passing near a star is vanishingly small. Indeed, explorers have not come upon many rogues even in mid-space. An actual capture must be so rare that the case you found may well be unique in the galaxy.
(Read more about rogue planets)
Scroll down for more stories in the same category. (Story submitted 10/25/2020)