Sunspot Observations during the Maunder Minimum from the Correspondence of John Flamsteed

TL;DR

This paper compiles and analyzes John Flamsteed's sunspot observations from 1672-1703 during the Maunder Minimum, estimating solar activity levels and comparing them with recent reconstructions, also discussing a possible white-light flare observed in 1705.

Contribution

It provides the first detailed compilation and analysis of Flamsteed's sunspot records from the Maunder Minimum period, including original texts and activity estimates.

Findings

Sunspot activity levels consistent with a grand solar minimum.

Comparison with recent reconstructions supports the historical data.

Discussion of a potential white-light flare observed in 1705.

Abstract

We compile and analyze the sunspot observations made by John Flamsteed for the period 1672-1703, corresponding to the second part of the Maunder Minimum, which appear in the correspondence of this famous astronomer. We include in an appendix the original texts of the sunspot records kept by Flamsteed. We compute an estimate of the level of solar activity using these records, and compare the results with the latest reconstructions of solar activity during the Maunder Minimum, obtaining values characteristic of a grand solar minimum. Finally, we discuss a phenomenon observed and described by Stephen Gray in 1705 that has been interpreted as a white-light flare.