Astronomers discover huge solitary planet based on radio emissions radio

Using the Karl G. Jansky Very Large Array in the United States, astronomers have discovered a solitary exoplanet based on its radio emissions. The planet is much more massive than Jupiter and has a relatively strong magnetic field.

The planet, called SIMP J01365663+0933473, is 20 light-years away from Earth. The object has 12 times the mass of Jupiter, but only 1.2 times the radius of Jupiter. It is the first time that a planet-like object outside our solar system has been discovered by means of its radio emission. According to the researchers, this way of detecting the radio emissions could become a new way to discover exoplanets.

It is also the first time that the magnetic field of a so-called solitary planet or orphan planet has been mapped. These are planets that do not orbit a star as usual. Its magnetic field would be 200 times stronger than Jupiter’s and millions of times stronger than Earth’s magnetic field. Jupiter’s magnetic field is 20,000 times stronger than Earth’s. The discovery may eventually reveal more about the magnetic processes in stars and planets.

The magnetic field creates an aurora, although it’s not clear exactly how that happens; it works in a different way than with the aurora on earth, where electrically charged particles from the sun provide the green spectacle. However, SIMP has no star, so the particles there may have come from a moon, as is the case with Jupiter’s moon Io.

The object was discovered as early as 2016 and was then classified as a brown dwarf along with four other objects. These are celestial bodies that are smaller in mass than stars but larger than gas giants such as Jupiter. It was suspected to be a very large brown dwarf, until a group of independent scientists determined that the object should be considered a planet after all.

On SIMP J01365663+0933473 it is about 825 degrees Celsius. Venus, the hottest planet in our solar system, has a temperature of 470 degrees, mainly due to the radiation from the sun. The massive exoplanet doesn’t orbit a star, so the heat probably still comes from the planet’s formation some 200 million years ago. The research is published under the title The Strongest Magnetic Fields on the Coolest Brown Dwarfs.