During Solar Cycle 24, which started at the end of 2008, the Sun was calm, and there were not many spectacular geoeffective events. In this article, we analyze the geomagnetic storm that happened on 15 July 2012 during the 602nd anniversary of the Polish Battle of Grunwald, thus we propose this event to be called the “Battle of Grunwald Day Storm”. According to NOAA scale, it was a G3 geomagnetic storm with a southward component of the heliospheric magnetic field, $Bz$ , falling to −20 nT, minimum Dst index of −139 nT, AE index of 1368 nT, and Ap index of 132 nT. It was preceded by a solar flare class X1.4 on 12 July. This geomagnetic storm was associated with the fast halo coronal mass ejection at 16:48:05 UT on 12 July, first appearance in the Large Angle and Spectroscopic Coronagraph C2, with a plane-of-sky speed of 885 km s−1 and maximum of 1415 km s−1. This geomagnetic storm was classified as the fourth strongest geomagnetic storm of Solar Cycle 24. At that time, a significant growth in the failures of the Polish electric transmission lines was observed, which could have a solar origin.

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2012 年 7 月 14 日至 15 日的太阳事件及其地质效应

在 2008 年底开始的第 24 太阳周期期间，太阳是平静的，没有太多壮观的地球效应事件。在本文中，我们分析了 2012 年 7 月 15 日波兰格伦瓦尔德战役 602 周年期间发生的地磁风暴，因此我们建议将此事件称为“格伦瓦尔德之战日风暴”。根据NOAA的尺度，这是一次G3地磁暴，太阳圈磁场的南向分量$Bz$下降到-20 nT，最小Dst指数为-139 nT，AE指数为1368 nT，Ap指数为132 nT。在它之前是 7 月 12 日的 X1.4 级太阳耀斑。这场地磁风暴与 7 月 12 日 16:48:05 UT 的快速晕日冕物质抛射有关，首次出现在大角度和光谱日冕仪 C2 中，天空速度为 885 km s-1，最大值为 1415 km s-1。这次地磁风暴被归类为太阳活动周期 24 中第四强的地磁风暴。当时，观察到波兰输电线路的故障显着增加，这可能源于太阳。