Zorza polarna na moment przed wykluciem się z zorzastego jajka, czyli nowozelandzki SAR
czyli #apod na dziś
https://apod.nasa.gov/apod/astropix.html
Image Credit & Copyright: Tristian McDonald
Na zdjęciu widzimy zorzę polarną otoczoną tzw. Stable Auroral Red (SAR) arc. Jest to dość świeżo poznane zjawisko, o którym nie znalazłem zbyt wiele polskiej literatury a że nie do końca jestem dobry w tłumaczenie w locie technicznych zawiłości, to odsyłam do opisu ze strony NASA, autorstwa Tiffany Lewis (Michigan Tech U.)
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 Earth's poles. However, it also traps a ring of ions closer to the equator, where they can gain energy from the magnetosphere during high solar activity. The energetic electrons in this ion ring can collide with and excite oxygen higher in Earth's ionosphere than typical auroras, causing the oxygen to glow red. Ongoing research has uncovered evidence that a red SAR arc can even transform into a purple and green STEVE.
A mniej więcej na środku, "za" zorzą możemy jeszcze dojrzeć oba Obłoki Magellana
#astronomia #astrofotografia #fotografia #oczkcontent
