相关论文: A Recount of Sunspot Groups on Staudach's Drawings
A long time-series of sunspot observations is preserved from Samuel Heinrich Schwabe who made notes and drawings of sunspots from 1825-1867. Schwabe's observing records are preserved in the manuscript archives of the Royal Astronomical…
Early observations of sunspot were realised by the naked eye. Possible utilization of these records for studying the long-term change in the Sun is discussed here. Other historical sunspot observations with camera obscuras are also…
Most of our knowledge about the Sun's activity cycle arises from sunspot observations over the last centuries since telescopes have been used for astronomy. The German astronomer Gustav Sp\"orer observed almost daily the Sun from 1861 until…
Samuel Heinrich Schwabe made 8486 drawings of the solar disk with sunspots in the period from November 5, 1825 to December 29, 1867. We have measured sunspot sizes and heliographic positions on digitized images of these drawings. A total of…
Our knowledge of the long-term evolution of solar activity and of its primary modulation, the 11-year cycle, largely depends on a single direct observational record: the visual sunspot counts that retrace the last 4 centuries, since the…
Much of our knowledge about the solar dynamo is based on sunspot observations. It is thus desirable to extend the set of positional and morphological data of sunspots into the past. Gustav Sp\"orer observed in Germany from Anklam…
Digital images of the observations printed in the books "Rosa Ursina sive solis" and "Prodromus pro sole mobili" by Christoph Scheiner as well as the drawings from Scheiner's letters to Marcus Welser are analysed in order to obtain…
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 the observer with the highest daily number of sunspot groups…
A revision is presented of the sunspot observations made by Charles Malapert from 1618 to 1626, studying several documentary sources that include those observations. The revised accounting of the group numbers recorded by Malapert for that…
Extending the knowledge about the properties of solar cycles into the past is essential for understanding the solar dynamo. This paper aims at estimating areas of sunspots observed by Schwabe in 1825-1867 and at calculating the tilt angles…
Sunspot number series are composed from observations of hundreds of different observers that requires careful normalization of the observers to the standard conditions. Here we present a new normalized series of the number of sunspot groups…
We revisit the sunspot drawings made by the Japanese astronomer Kunitomo Toubei during 1835-1836 and recount the sunspot group number for each image. There are two series of drawings, preliminary (P, containing 17 days with observations)…
The focus of this article is a re-count of Richard Carrington's original sunspot observations from his book drawings (Carrington,1863) by an observer from the World data Center-SILSO network, Thomas H. Teague(UK). This modern recount will…
The sunspot groups have been observed since 1610 and their numbers have been used for evaluating the amplitude of solar activity. Daniel M\"ogling recorded his sunspot observations for more than 100 days in 1626 - 1629 and formed a…
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, around the maximum phase of the Solar Cycle 6. These…
The original sunspot observations by Heinrich Samuel Schwabe of 1825-1867 were digitized and a first subset of spots was measured. In this initial project, we determined more than 14 000 sunspot positions and areas comprising about 11% of…
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). The main changes are the elimination of a considerable…
Sunspot observations with telescopes in 18th century were carried out in Japan as well. One of these sunspot observations is recorded in an account called Sansaizusetsu narabini Kansei irai Jissoku Zusetsu (Charts of Three Worlds and…
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 in the current sunspot group database, used as a basis to…
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 from 1830 to 1843, just after the Dalton Minimum. We have…