A star field appears above a town at night. The left part of the sky shows a pinkish-red glow that is an aurora, while the right part of the sky shows a smoother and darker glow that is a SAR arc. Please see the explanation for more detailed information.
夜晚，城镇上方出现星空。天空左侧出现粉红色辉光，这是极光，而天空右侧出现更平滑、更暗的辉光，这是稳定极光红弧。有关更多详细信息，请参阅说明。
See Explanation. Clicking on the video will download the highest resolution version available.
请参阅说明。单击视频将下载可用的最高分辨率版本。
2024年1月3日 A SAR Arc from New Zealand Image Credit & Copyright: Tristian McDonald; Text: Tiffany Lewis (Michigan Tech U.) Explanation: What is that unusual red halo surrounding this aurora? It is a Stable Auroral Red (SAR) arc. SAR arcs are rare and have only been acknowledged and studied since 1954. The featured wide-angle photograph, capturing nearly an entire SAR arc surrounding more common green and red aurora, was taken earlier this month from Poolburn, New Zealand, during an especially energetic geomagnetic storm. Why SAR arcs form remains a topic of research, but is likely related to Earth’s protective magnetic field, a field created by molten iron flowing deep inside the Earth. This magnetic field usually redirects incoming charged particles from the Sun’s wind toward the…
2023年11月11日 The SAR and the Milky Way Image Credit & Copyright: Julien Looten Explanation: This broad, luminous red arc was a surprising visitor to partly cloudy evening skies over northern France. Captured extending toward the zenith in a west-to-east mosaic of images from November 5, the faint atmospheric ribbon of light is an example of a Stable Auroral Red (SAR) arc. The rare night sky phenomenon was also spotted at unusually low latitudes around world, along with more dynamic auroral displays during an intense geomagnetic storm. SAR arcs and their relation to auroral emission have been explored by citizen science and satellite investigations. From altitudes substantially above the normal auroral glow, the deep red SAR emission is thought to be caused by strong heating due…
