Auroras also occur outside our solar system
New evidence obtained by University of Leicester planetary scientists have suggested that auroras -- similar to Earth's Aurora Borealis -- also occur on bodies outside our solar system.
Auroras occur on several planets within our solar system, and the brightest -- on Jupiter -- are 100 times brighter than those on Earth. However, no auroras have yet been observed beyond Neptune.
A new study led by University of Leicester lecturer Dr. Jonathan Nichols has shown that processes strikingly similar to those which power Jupiter's auroras could be responsible for radio emissions detected from a number of objects outside our solar system.
In addition, the radio emissions are powerful enough to be detectable across interstellar distances -- meaning that auroras could provide an effective way of observing new objects outside our solar system.
Auroras occur when charged particles in an object's magnetosphere collide with atoms in its upper atmosphere, causing them to glow. However, before hitting the atmosphere, these particles also emit radio waves into space.
The study suggested that this phenomenon is not limited to our solar system.
It showed that the radio emissions from a number of ultracool dwarfs might be caused in a very similar, but significantly more powerful, way to Jupiter's auroras.
"We have recently shown that beefed-up versions of the auroral processes on Jupiter are able to account for the radio emissions observed from certain 'ultracool dwarfs' -- bodies which comprise the very lowest mass stars -- and 'brown dwarfs' -- 'failed stars' which lie in-between planets and stars in terms of mass," said Dr. Nichols, a Lecturer and Research Fellow in the University of Leicester's Department of Physics and Astronomy.
"These results strongly suggest that auroras do occur on bodies outside our solar system, and the auroral radio emissions are powerful enough -- one hundred thousand times brighter than Jupiter's -- to be detectable across interstellar distances," he added.
The study recently appeared in the Astrophysical Journal.