Properties of solar activity in the Dalton minimum

对太阳活动周期变化的精确认识对于理解太阳大规模磁场的产生是必不可少的。除了17世纪下半叶的蒙德极小期（几十年来太阳黑子很少）得到了很好的研究外，1800年左右的道尔顿极小期（Dalton minimum）还没有得到很好的研究。利用哥本哈根天文台的原始太阳黑子测量数据和honor<s:1> Flaugergues的凌日观测数据，该方案旨在获得大量新的太阳黑子位置和区域、太阳黑子群倾斜角度和道尔顿极小值周围时间的极性分离。这些位置也将使我们能够确定太阳在道尔顿极小值之前的微分旋转。这个周期与目前的低周期24和太阳活动的未来发展相比较是有趣的。

The precise knowledge of the variability of the solar activity cycle is essential for the understanding of the generation of large-scale magnetic fields in the Sun. Apart from the well studied Maunder minimum in the second half of the 17th century with very few sunspots for several decades, the Dalton minimum around 1800 is not investigated well. With the original sunspot measurements of Copenhagen Observatory and the transit observations by Honoré Flaugergues, the proposal aims to obtain a large number of new sunspot positions and areas, sunspot group tilt angles and polarity separations for the time around the Dalton minimum. The positions will also allow us to determine the differential rotation of the Sun just before the Dalton minimum. The period is interesting for a comparison with the present low cycle 24 and the future development of solar activity.