活跃太阳的黑子

活跃太阳的黑子

ByNASA中文

2023年7月11日 Sunspots on an Active Sun Image Credit: NASA, SDO; Processing & Copyright: Şenol Şanlı Explanation: Why is our Sun so active now? No one is sure. An increase in surface activity was expected because our Sun is approaching solar maximum in 2025. However, last month our Sun sprouted more sunspots than in any month during the entire previous 11-year solar cycle — and even dating back to 2002. The featured picture is a composite of images taken every day from January to June by NASA‘s Solar Dynamic Observatory. Showing a high abundance of sunspots, large individual spots can be tracked across the Sun’s disk, left to right, over about two weeks. As a solar cycle continues, sunspots typically appear closer to the equator. Sunspots…

绿光的国度: 挪威上空的极光

绿光的国度: 挪威上空的极光

ByNASA中文

2023年1月22日 In Green Company: Aurora over Norway Image Credit & Copyright: Max Rive Explanation: Raise your arms if you see an aurora. With those instructions, two nights went by with, well, clouds — mostly. On the third night of returning to same peaks, though, the sky not only cleared up but lit up with a spectacular auroral display. Arms went high in the air, patience and experience paid off, and the creative featured image was captured as a composite from three separate exposures. The setting is a summit of the Austnesfjorden fjord close to the town of Svolvear on the Lofoten islands in northern Norway. The time was early 2014. Although our Sun passed the solar minimum of its 11-year cycle only a few years…