标题： 1872年2月的极端空间天气事件：太阳黑子、磁扰动和极光显示 显示英文标题

标题： The Extreme Space Weather Event of 1872 February: Sunspots, Magnetic Disturbance, and Auroral Displays

摘要： 我们回顾了1872年2月4日极地磁暴期间的太阳活动观测、地磁变化和极光可见性。 这次极地磁暴（以下简称查普曼-西尔弗曼磁暴）显然起源于一个面积适中的复杂活动区（\approx 500{\mu }sh），该活动区位于盘面中心附近（S19{\deg }E05{\deg }）。 有迹象表明，1872年2月3日9-10 UT期间，该区域发生了一次爆发，根据该区域的位置、复杂性和演化，以及关于日珥激活的报告，可以得出地球上的可能传播时间为\approx 29小时。 磁图显示，磁暴于\approx 14:27 UT开始，并允许最小的DST估计值为{\pounds }-834 nT。 在雅各布阿巴德（英属印度）和上海（中国）都可靠地报道了高纬度极光现象，两地的磁纬度（MLAT）均为19{\deg }.9，不变纬度（ILAT）为24{\deg }.2。 1872年风暴期间，在磁纬度低于|20|{\deg }的13个地点观测到了极光的可见性（磁纬度范围为|10{\deg }.0|--|19{\deg }.9|），而1859年风暴和1921年风暴分别只有一个地点观测到极光，磁纬度分别为|17{\deg }.3|和|16.{\deg }2|。 极光扩展和保守的磁暴强度表明，这次磁暴的强度与1859年9月（25{\deg }.1 \pm 0{\deg }.5 ILAT 和 -949 \pm 31 nT）以及1921年5月（27{\deg }.1 ILAT 和 -907 \pm 132 nT）的极端磁暴相当，这使得1872年的磁暴成为已观测到的三大最强磁暴之一。 显示英文摘要

摘要： We review observations of solar activity, geomagnetic variation, and auroral visibility for the extreme geomagnetic storm on 1872 February 4. The extreme storm (referred to here as the Chapman-Silverman storm) apparently originated from a complex active region of moderate area (\approx 500 {\mu}sh) that was favorably situated near disk center (S19{\deg} E05{\deg}). There is circumstantial evidence for an eruption from this region at 9--10 UT on 1872 February 3, based on the location, complexity, and evolution of the region, and on reports of prominence activations, which yields a plausible transit time of \approx29 hr to Earth. Magnetograms show that the storm began with a sudden commencement at \approx14:27 UT and allow a minimum Dst estimate of {\pounds} -834 nT. Overhead aurorae were credibly reported at Jacobabad (British India) and Shanghai (China), both at 19{\deg}.9 in magnetic latitude (MLAT) and 24{\deg}. 2 in invariant latitude (ILAT). Auroral visibility was reported from 13 locations with MLAT below |20|{\deg} for the 1872 storm (ranging from |10{\deg}. 0|--|19{\deg}. 9| MLAT) versus one each for the 1859 storm (|17{\deg}. 3| MLAT) and the 1921 storm (|16.{\deg}2| MLAT). The auroral extension and conservative storm intensity indicate a magnetic storm of comparable strength to the extreme storms of 1859 September (25{\deg}.1 \pm 0{\deg}.5 ILAT and -949 \pm 31 nT) and 1921 May (27{\deg}.1 ILAT and -907 \pm 132 nT), which places the 1872 storm among the three largest magnetic storms yet observed.