On 29 April, 2015, three satellite observatories—NuSTAR, Hinode, and Solar Dynamics Observatory—all stared at our Sun. This image merges data from Nuclear Spectroscopic Telescope Array, or NuSTAR (high-energy x-rays shown in blue), Japan’s Hinode spacecraft (low-energy x-rays in green), and SDO (extreme UV in yellow and red). The blue-white NuSTAR data pinpoint the most energetic areas.
During a December, 2013, solar flare, three satellites watched a current sheet form. This animation shows four views of the flare from the Solar Dynamics Observatory, the Solar and Terrestrial Relations Observatory, and JAXA’s Hinode. The current sheet is a long, thin structure, especially visible in the views on the left. Those two animations depict light emitted by material with higher temperatures, so they better show the extremely hot current sheet.
A current sheet is a very fast, very flat flow of electrically-charged material, extremely thin compared to its length and width. Current sheets form when two oppositely-aligned magnetic fields come in close contact, creating very high magnetic force.
Venus is just crossing the edge of the Sun at the beginning of its recent transit in this image from the Hinode spacecraft. The thin ring of light seen surrounding the planet’s dark silhouette is sunlight refracted by Venus’ thick atmosphere.