18 citations · 20 across the 4 of their papers we have counts for
4 papers
Sunspot Observations in 1684-1702: John Flamsteed and Philippe de La Hire
Nadezhda Zolotova, Mikhail Vokhmyanin
In this work, we present an extensive review and detailed analysis of sunspot measurements, drawings, and engravings made by John Flamsteed and, mainly, by Philippe de La Hire duri…
On the Penumbra-to-Umbra Ratio from 1660 to 1676
Nadezhda Zolotova, Mikhail Vokhmyanin
Sunspot engravings made in the Maunder minimum are used to evaluate the fine structure of sunspots. Based on 78 images of the full solar disk and 77 images of individual sunspots,…
Long-lived sunspots in historical records: a case study analysis from 1660 to 1676
Nadezhda Zolotova, Mikhail Vokhmyanin
Sunspot engravings and measurements in 1660-1676 are analyzed to retrieve sunspot area and heliocoordinates. Based on these data, we revise the Hoyt and Schatten (The role of the s…
The Extreme Space Weather Event of 1872 February: Sunspots, Magnetic Disturbance, and Auroral Displays
Hisashi Hayakawa, Edward W. Cliver, Frédéric Clette +19
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…