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.
Three spacecraft built in Europe and Japan have completed their final joint tests to ensure they are ready for departure to Mercury on an Ariane 5 rocket late next year on the nearly £1.5 billion BepiColombo mission to survey the Solar System’s innermost planet.
NASA’s Cassini spacecraft has observed geysers erupting on Saturn’s icy moon Enceladus since 2005, but the process that drives and sustains these eruptions has remained a mystery. Now, scientists have pinpointed a mechanism by which cyclical tidal stresses exerted by Saturn can drive Enceladus’s long-lived eruptions.
Extra testing of the James Webb Space Telescope and delays in assembling the powerful observatory will push back the $10 billion mission’s launch by at least six months to early 2019, officials announced last week as the telescope successfully completed an extensive performance test inside a cryogenic vacuum chamber in Houston.
