158 citations · 583 across the 18 of their papers we have counts for
18 papers
Revisiting Christoph Scheiner's Sunspot Records: a New Perspective on Solar Activity of the Early Telescopic Era
V. M. S. Carrasco, A. Muñoz-Jaramillo, M. C. Gallego +1
Christoph Scheiner was one of the most outstanding astronomers in the history of the sunspot observations. His book, Rosa Ursina, is the reference work regarding the study of the e…
Revisiting the Amplitude of Solar Cycle 9: The Case of Sunspot Observations by W.C. Bond
V. M. S. Carrasco, M. C. Gallego, R. Arlt +1
William Cranch Bond, director of the Harvard College Observatory in mid-19th century, carried out detailed sunspot observations during the period 1847-1849. We highlight Bond was t…
Sunspot Records by Antonio Colla just after the Dalton Minimum
V. M. S. Carrasco, C. Bertolin, F. Domínguez-Castro +3
Antonio Colla was a meteorologist and astronomer who made sunspot observations at the Meteorological Observatory of the Parma University (Italy). He carried out his sunspot records…
Number of Sunspot Groups from the Galileo-Scheiner controversy revisited
V. M. S. Carrasco, M. C. Gallego, J. M. Vaquero
We revise the sunspot observations made by Galileo Galilei and Christoph Scheiner in the context of their controversy on the nature of sunspots. Their sunspot records not included…
Sunspot characteristics at the onset of the Maunder Minimum based on the observations of Hevelius
V. M. S. Carrasco, J. M. Vaquero, M. C. Gallego +8
An analysis of the sunspot observations made by Hevelius during 1642-1645 is presented. These records are the only systematic sunspot observations just before the Maunder Minimum.…
On the use of naked-eye sunspot observations during the Maunder Minimum
V. M. S. Carrasco, M. C. Gallego, R. Arlt +1
Naked-eye sunspot observations (NESO, hereafter) have been recorded for last two millennia, approximately. This kind of records were made around the world, mainly in Asian civiliza…
The Extreme Space Weather Event in 1903 October/November: An Outburst from the Quiet Sun
Hisashi Hayakawa, Paulo Ribeiro, José M. Vaquero +11
While the Sun is generally more eruptive during its maximum and declining phases, observational evidence shows certain cases of powerful solar eruptions during the quiet phase of t…
A Great Space Weather Event in February 1730
Hisashi Hayakawa, Yusuke Ebihara, José M. Vaquero +9
Aims. Historical records provide evidence of extreme magnetic storms with equatorward auroral extensions before the epoch of systematic magnetic observations. One significant magne…
Sunspot Observations Made by Hallaschka during the Dalton Minimum
V. M. S. Carrasco, J. M. Vaquero, R. Arlt +1
We present and analyse the sunspot observations performed by Franz I. C. Hallaschka in 1814 and 1816. These solar observations were carried out during the so-called Dalton minimum,…
Could a Hexagonal Sunspot Have Been Observed During the Maunder Minimum?
V. M. S. Carrasco, J. M. Vaquero, M. C. Gallego
The Maunder Minimum was the period between 1645 and 1715 whose main characteristic was abnormally low and prolonged solar activity. However, some authors have doubted this low leve…
A Revised Collection of Sunspot Group Numbers
J. M. Vaquero, L. Svalgaard, V. M. S. Carrasco +7
We describe a revised collection of the number of sunspot groups from 1610 to the present. This new collection is based on the work of Hoyt and Schatten (Solar Phys. 179, 189, 1998…
Equivalence relations between the Cortie and Zurich sunspot group morphological classifications
V. M. S. Carrasco, L. Lefevre, J. M. Vaquero +1
Catalogues of sunspots have been available with useful information about sunspots or sunspot groups for approximately the last 150 years. However, the task of merging these catalog…
Sunspot Numbers and Areas from the Madrid Astronomical Observatory (1876-1986)
A. J. P. Aparicio, J. M. Vaquero, V. M. S. Carrasco +1
The solar program of the Astronomical Observatory of Madrid started in 1876. For ten solar cycles, observations were made in this institution to determine sunspot numbers and areas…
Long-term Spatial and Temporal Variations of Aurora Borealis Events in the Period 1700--1905
M. Vázquez, J. M. Vaquero, M. C. Gallego
Catalogues and other records of aurora-borealis events were used to study the long-term spatial and temporal variation of these phenomena in the period from 1700 to 1905 in the Nor…
Forty two years counting spots: solar observations by D. E. Hadden during 1890-1931 revisited
V. M. S. Carrasco, J. M. Vaquero, M. C. Gallego +1
We have recovered the sunspot observations made by David E. Hadden during 1890-1931 from Alta, Iowa. We have digitized the available data published by Hadden in different astronomi…
A Simple Method to Check the Reliability of Annual Sunspot Number in the Historical Period 1610-1847
J. M. Vaquero, R. M. Trigo, M. C. Gallego
A simple method to detect inconsistencies in low annual sunspot numbers based on the relationship between these values and the annual number of active days is described. The analys…
Revisited sunspot data: A new scenario for the onset of the Maunder minimum
J. M. Vaquero, M. C. Gallego, I. G. Usoskin +1
Maunder Minimum forms an archetype for the Grand minima, and detailed knowledge of its temporal development has important consequences for the solar dynamo theory dealing with long…
155-day Periodicity in Solar Cycles 3 and 4
J. M. Vaquero, R. M. Trigo, M. Vazquez +1
The near 155 days solar periodicity, so called Rieger periodicity, was first detected in solar flares data and later confirmed with other important solar indices. Unfortunately, a…