X-rays have been detected in several planets within our solar system, such as in Jupiter and Saturn's rings, but researchers have not seen anything beaming from our most distant ice giants, Uranus and Neptune—until now.
Astronomers using NASA's Chandra X-ray Observatory have discovered X-rays coming out of Uranus for the first time, which may reveal more secrets about the seventh planet from the sun, reports Wilson Wong for NBC News. The new study was published this month in the Journal of Geophysical Research.
Uranus is a strange planet with many unusual characteristics, including its 13 rings and 27 moons. The seventh planet also spins on its side, and it was the first planet found using a telescope. Using images taken by Chandra's Advanced CCD Imaging Spectrometer in 2002 and Chandra's High-Resolution Camera in 2017, researchers observed Uranus emitting faint X-rays, reports George Dvorsky for Gizmodo. The recently reviewed 2002 images revealed a precise detection of the X-rays, and the 2017 images showed a slight flare, reports CNN's Rob Picheta.
Researchers suspect that the X-rays observed are either from fluorescence, auroral emissions, or scattered solar X-rays. Like Jupiter and Saturn, Uranus may scatter X-rays given off by the sun, but not all the X-rays detected on Uranus can be explained by this, CNN reports. Researchers suspect the ice giant may be emitting X-rays through its rings like Saturn does. Uranus's rings may be emitting X-rays when charged particles in the space collide with them, also known as fluorescence, Gizmodo reports. Auroral emissions could be another viable option, but auroras on Uranus are not fully understood and more observations are needed, reports Gizmodo.
In the image above, the pink splotch shows the X-rays detected in 2002 imposed on a photo of Uranus taken in 2004 at the same orientation. Researchers are interested in studying X-rays emitted from Uranus because of its unusual spin axis and magnetic field.
Unlike other planets, Uranus spins on its side, and its rotation axis is almost parallel to its orbit around the Sun. Uranus's magnetic field is also offset from its center, NASA explains in a statement. Scientists could further analyze these unusual characteristics of Uranus by studying the planet's X-ray emissions, CNN reports.
The X-rays could also give clues about Uranus's surface, atmosphere, and ring composition. Further investigating the beams may also give astronomers a better understanding of how black holes and neutron stars also emit X-rays.