A night sky is shown with a bright red band running overhead. Above the red band is a diffuse red glow. A path through a grassy filed is in the foreground with a path going out toward the horizon. Please see the explanation for more detailed information.
夜空中，一条明亮的红色光带从头顶划过。红带上方是漫天的红光。前景是一条穿过草地的小路，小路向地平线延伸。有关更多详细信息，请参阅说明。
2023年9月27日 STEVE and Milky Way Cross over Rural Road Image Credit & Copyright: Theresa Clarke Explanation: Not every road ends in a STEVE. A week ago, a sky enthusiast’s journey began with a goal: to photograph an aurora over Lake Huron. Driving through rural Ontario, Canada, the forecasted sky show started unexpectedly early, causing the photographer to stop before arriving at the scenic Great Lake. Aurora images were taken toward the north — but over land, not sea. While waiting for a second round of auroras, a peculiar band of light was noticed to the west. Slowly, the photographer and friends realized that this western band was likely an unusual type of aurora: a Strong Thermal Emission Velocity Enhancement (STEVE). Moreover, this STEVE was putting…
2021年05月05日 STEVE over Copper Harbor Image Credit & Copyright: MaryBeth Kiczenski Explanation: What creates STEVEs? Strong Thermal Emission Velocity Enhancements (STEVEs) have likely been seen since antiquity, but only in the past five years has it been realized that their colors and shapes make them different from auroras. Seen as single bright streaks of pink and purple, the origin of STEVEs remain an active topic of research. STEVEs may be related to subauroral ion drifts (SAIDs), a supersonic river of hot atmospheric ions. For reasons currently unknown, STEVEs are frequently accompanied by green “picket-fence” auroras. The featured STEVE image is a combination of foreground and background exposures taken consecutively in mid-March from Copper Harbor, Michigan, USA. This bright STEVE lasted several minutes, spanned from horizon…
2020年11月17日 A Glowing STEVE and the Milky Way Image Credit: NASA, Krista Trinder Explanation: What’s creating these long glowing streaks in the sky? No one is sure. Known as Strong Thermal Emission Velocity Enhancements (STEVEs), these luminous light-purple sky ribbons may resemble regular auroras, but recent research reveals significant differences. A STEVE’s great length and unusual colors, when measured precisely, indicate that it may be related to a subauroral ion drift (SAID), a supersonic river of hot atmospheric ions thought previously to be invisible. Some STEVEs are now also thought to be accompanied by green picket fence structures, a series of sky slats that can appear outside of the main auroral oval that does not involve much glowing nitrogen. The featured wide-angle composite image shows…
