Astronomers Discover Rogue World with Wild Auroras

Astronomers using the National Science Foundation's Karl G. Jansky Very Large Array (VLA) have discovered a free-floating world with a powerful magnetic field four million times stronger than the one around Earth. This rogue planet is a world drifting in space between stars.

Known as SIMP J01365663+0933473 by astronomers, this newly-discovered world is only 20 light-years from Earth. This is the first ever planetary-mass object to be detected by radio telescopes and the first time scientists have measured the magnetic field of one of these rogue worlds.

It is suspected that the aurora produced on this world are more similar to Jupiter's than Earth's due to a suspected moon.. On Earth, the aurora are a by-product of solar wind particles bombarding the planet's magnetic field. To contrast, Jupiter's auroras are produced primarily by charged particles coming from its volcanically active moon Io.

"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," said Melodie Kao at Arizona State University, lead scientist of this study. "We think these mechanisms can work not only in brown dwarfs, but also in both gas giant and terrestrial planets."

It is currently estimated that there might be one Jupiter-mass rogue planet for every four stars in our galaxy. Observations of these free-floating worlds have helped to readjust this estimate over time.

Read more about this fascinating story at: http://earthsky.org/space/rogue-planet-powerful-magnetic-field-brilliant-auroras

Or read the full study here: http://iopscience.iop.org/article/10.3847/1538-4365/aac2d5

Image Credits: Caltech/Chuck Carter/NRAO/AUI/NSF