Jupiter
Credit: X-ray: NASA/CXC/UCL/W.Dunn et al, Optical: NASA/STScI
Solar storms are triggering X-ray auroras on Jupiter that are about
eight times brighter than normal over a large area of the planet and
hundreds of times more energetic than Earth's 'northern lights,' according to a new study using data from NASA's Chandra X-ray Observatory.
This result is the first time that Jupiter's auroras have been studied
in X-ray light when a giant solar storm arrived at the planet.
The Sun constantly ejects streams of particles into space in the solar wind.
Sometimes, giant storms, known as coronal mass ejections (CMEs), erupt
and the winds become much stronger. These events compress Jupiter's
magnetosphere, the region of space controlled by Jupiter's magnetic
field, shifting its boundary with the solar wind inward by more than a
million miles. This new study found that the interaction at the boundary
triggers the X-rays in Jupiter's auroras, which cover an area bigger
than the surface of the Earth.
These composite images show Jupiter and its aurora during and after a
CME's arrival at Jupiter in October 2011. In these images, X-ray data
from Chandra (purple) have been overlaid on an optical image from the
Hubble Space Telescope. The left-hand panel reveals the X-ray activity
when the CME reached Jupiter, and the right-hand side is the view two
days later after the CME subsided. The impact of the CME on Jupiter's
aurora was tracked by monitoring the X-rays emitted during two 11-hour
observations. The scientists used that data to pinpoint the source of
the X-ray activity and identify areas to investigate further at
different time points. They plan to find out how the X-rays form by
collecting data on Jupiter's magnetic field, magnetosphere and aurora
using Chandra and ESA's XMM-Newton.
A paper describing these results appeared in the March 22, 2016
issue of the Journal of Geophysical Research. The authors on the paper
are William Dunn (UCL), Graziella Branduardi-Raymont (UCL), Ronald
Elsner (NASA's Marshall Space Flight Center), Marissa Vogt (Boston
University), Laurent Lamy (University of Paris Diderot), Peter Ford
(Massachusetts Institute of Technology), Andrew Coates (UCL), Randall
Gladstone (Southwest Research Institute), Caitriona Jackman (University
of Southampton), Jonathan Nichols (University of Leicester), Jonathan
Rae (UCL), Ali Varsani (UCL), Tomoki Kimura (JAXA), Kenneth Hansen
(University of Michigan), and Jamie Jasinski (UCL).
NASA's Marshall Space Flight Center in Huntsville, Alabama, manages
the Chandra program for NASA's Science Mission Directorate in
Washington. The Smithsonian Astrophysical Observatory in Cambridge,
Massachusetts, controls Chandra's science and flight operations.
Fast Facts for Jupiter:
Scale: Each image is 60 arcsec across.
Category: Solar System
Observation Date: 02 Oct 2011 and 04 Oct 2011
Observation Time: 10 hours 50 minutes each pointing.
Obs. ID: 12315, 12316
Instrument: ACIS
References: Dunn, W. et al, 2016, JGR (accepted)
Color Code: X-ray (Purple); Optical (Red, Green, Blue)
Distance Estimate: About 650 million kilometers
Source: NASA’s Chandra X-ray Observatory
