Astronomers detected giant rogue planet bumbling around space

An object is at the boundary between a giant planet and a brown dwarf.

Artist's conception of SIMP J01365663+0933473, an object with 12.7 times the mass of Jupiter, but a magnetic field 200 times more powerful than Jupiter's. This object is 20 light-years from Earth. Credit: Caltech/Chuck Carter; NRAO/AUI/NSF
Artist's conception of SIMP J01365663+0933473, an object with 12.7 times the mass of Jupiter, but a magnetic field 200 times more powerful than Jupiter's. This object is 20 light-years from Earth. Credit: Caltech/Chuck Carter; NRAO/AUI/NSF

Astronomers using the National Science Foundation’s Karl G. Jansky Very Large Array (VLA) have discovered a new evidence of a giant rogue planet outside our solar system. The planet which is expected to 12 times larger than Jupiter, found traveling without any sort of set orbit or parent star.

From the radio astronomy observatory, scientists were able to pick up its magnetic activity and study it. Moreover, it has a surprisingly strong magnetic powerhouse and a “rogue”.

Melodie Kao, who led this study while a graduate student at Caltech said, “This object is right at the boundary between a planet and a brown dwarf, or ‘failed star,’ and is giving us some surprises that can potentially help us understand magnetic processes on both stars and planets.”

The strange object in the latest study, called SIMP J01365663+0933473, has a magnetic field more than 200 times stronger than Jupiter’s. The object was originally detected in 2016 as one of five brown dwarfs the scientists studied with the VLA to gain new knowledge about magnetic fields and the mechanisms by which some of the coolest such objects can produce strong radio emission. Brown dwarf masses are notoriously difficult to measure, and at the time, the object was thought to be an old and much more massive brown dwarf.

Last year, another team of scientists found that the SIMP J01365663+0933473 was part of a very young group of stars. It means, it was in fact so much less massive that it could be a free-floating planet — only 12.7 times more massive than Jupiter.

Scientists estimated that the temperature of the object is about 825 degrees Celsius or more than 1500 degrees Fahrenheit.

At the same time, the Caltech group that initially recognized its radio emission in 2016 had watched it again in another examination at significantly higher radio frequencies and affirmed that its magnetic field was much more grounded than first estimated.

Kao said, “When it was announced that SIMP J01365663+0933473 had a mass near the deuterium-burning limit, I had just finished analyzing its newest VLA data. The VLA observations provided both the first radio detection and the first measurement of the magnetic field of a possible planetary mass object beyond our Solar System.”

“This particular object is exciting because studying its magnetic dynamo mechanisms can give us new insights on how the same type of mechanisms can operate in extrasolar planets — planets beyond our Solar System. We think these mechanisms can work not only in brown dwarfs but also in both gas giant and terrestrial planets.”

Gregg Hallinan, of Caltech, said, “Such a strong magnetic field “presents huge challenges to our understanding of the dynamo mechanism that produces the magnetic fields in brown dwarfs and exoplanets and helps drive the auroras we see,”

“Detecting SIMP J01365663+0933473 with the VLA through its auroral radio emission also means that we may have a new way of detecting exoplanets, including the elusive rogue ones not orbiting a parent star.”

The findings are reported in the Astrophysical Journal.