This composite image shows Jupiter and its aurorae during a solar coronal mass ejections’s arrival at Jupiter on 2 October 2011. In the image, X-ray data from Chandra (purple) have been overlaid on an optical image from the NASA/ESA Hubble Space Telescope. Image credit: X-ray: NASA/CXC/UCL/W.Dunn et al, Optical: NASA/STScI.Solar storms are triggering X-ray aurorae 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 aurorae 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 aurorae, which cover an area bigger than the surface of the Earth.This composite image shows Jupiter and its aurorae on 4 October 2011, two days after a solar coronal mass ejection had subsided. In the image, X-ray data from Chandra (purple) have been overlaid on an optical image from the NASA/ESA Hubble Space Telescope. Image credit: X-ray: NASA/CXC/UCL/W.Dunn et al, Optical: NASA/STScI.The composite images above show Jupiter and its aurora during and after a CME’s arrival at Jupiter in October 2011. 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.
Observers in Western Europe with a clear sky around local midnight cannot fail to notice the conspicuous ‘star’ that is Jupiter low in the south. But look a span-and-a-half of an outstretched hand at arm’s length to Jupiter’s left and you’ll find another giant of the solar system – Saturn. The ringed planet is closest to Earth for 2019 on 9 July, so here is our quick observing guide.
The Moon’s thin atmosphere contains neon, a gas commonly used in electric signs on Earth because of its intense glow. While scientists have speculated on the presence of neon in the lunar atmosphere for decades, NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft has confirmed its existence for the first time.
With good weather predicted, UK observers are in for a early treat on the morning of Saturday, 24th January, when a rare triple shadow transit of Jupiter’s moons occurs — an event not to be repeated until 2032. If cloudy, Griffith Observatory in Los Angeles is hosting a live webcast.
