Located three thousand light-years from Earth is Kepler-160, a Sun-like star previously thought to have three small planets orbiting it. In a new study, scientists have indicated the potential existence of a fourth planet, naming it KOI-456.04.
This new planet is roughly the size of Earth and orbits Kepler-160 at a distance similar to that between us and the Sun, which gives scientists hope that it could be another candidate in the list of planets potentially capable of supporting life.
Most of the exoplanets discovered so far orbit red dwarf stars. This is not surprising to scientists, as red dwarfs are the most common stars in the universe. Additionally, our method of detecting exoplanets involves identifying the orbital path of the planet across the star – when the planet passes in front of the star, the amount of light emitted decreases slightly, allowing scientists to determine the size, orbit, and many other details about that exoplanet.
Red dwarfs are not very bright, emitting less energy and radiation than other stars, making it somewhat easier to detect transiting planets. The most famous red dwarf is probably Proxima Centauri (part of the Alpha Centauri system along with the binary stars Alpha Centauri A and Alpha Centauri B, Proxima Centauri is also the closest star to our Solar System, located just 4.243 light-years away); orbiting Proxima Centauri is an exoplanet named Proxima b, which has the potential to support life.
Continuing on the new discovery, in a research report published in the journal Astronomy and Astrophysics last Thursday, notable data about the exoplanet orbiting Kepler-160 has been highlighted.
From what astronomers have observed, KOI 456.04 is nearly double the size of Earth, orbits Kepler-160 at a distance similar to that of Earth from the Sun, and completes its orbit in 378 days. This is the most important point: KOI 456.04 receives about 93% of the sunlight that Earth receives from the Sun, positioned at a sufficient distance from the central star for liquid water to exist on its surface.
This data is significant because one of the reasons a red dwarf star may not support life is the amount of radiation it emits, which can scorch any budding life forms as well as the planet itself. In contrast, a relatively benign star like the Sun – theoretically, the same goes for Kepler-160 – is much more stable, with the potential to support life development.
The authors of the study discovered KOI-456.04 by analyzing old data obtained from the Kepler telescope. They applied two new algorithms to analyze the brightness emitted from Kepler-140, which allowed them to identify the new exoplanet.
Currently, the research team believes there is an 85% chance that KOI-456.04 is a true planet – an object must exceed a 99% probability to be officially recognized as an exoplanet. To confirm that 99% probability, astronomers need to continue monitoring this star system, and when the two NASA James Webb telescopes (scheduled for launch in 2021) and PLATO (expected to launch in 2026) officially become operational, we will be able to determine whether KOI-456.04 is a “sibling” of Earth.
Source: MIT Technology Review