It has recently been claimed that analysis of Greenwich sunspot data over 120 years reveals that sunspot activity clusters around two longitudes separated by 180 degrees (``active longitudes'') with clearly defined differential rotation during activity cycles.In the present work we extend this critical examination of methodology to the actual Greenwich sunspot data and also consider newly proposed methods of analysis claiming to confirm the original identification of active longitudes. Our analysis revealed that values obtained for the parameters of differential rotation are not stable across different methods of analysis proposed to track persistent active longitudes. Also, despite a very thorough search in parameter space, we were unable ...
Sunspots have been observed to undergo rotation about their umbral centre. This is typically a slow ...
Context.The search for active longitudes on the Sun has a long history, and many controversial resu...
International audienceVarious manifestations of solar activity are not uniformly distributed with he...
Context.It has recently been claimed that analysis of Greenwich sunspot data over 120 years reveals...
Abstract In this thesis solar active longitudes of X-ray flares and sunspots are studied. The fact t...
As recently found, the distribution of sunspots is non-axisymmetric and spot group formation implie...
A novel analysis of sunspot group data for the past 120 years reveals that sunspots in both northern...
Abstract. As recently found, the distribution of sunspots is non-axisymmetric and spot group formati...
We present an overview of the observational results related to the existence of long-lived sunspot a...
Context. The sunspots and other solar activity indicators tend to cluster on the surface of the Sun...
Context.Recently, it was found that two persistent active longitudes of sunspots separated by about...
Context. After considering the solar surface differential rotation, it was found that two persistent...
The modulation of solar activity closely follows the solar rotation period suggesting the existence ...
All A&A articles are in open access ONE year after their publication date (August 2013)Aims. The lat...
Context. Solar active longitudes and their rotation have been studied for a long time usin...
Sunspots have been observed to undergo rotation about their umbral centre. This is typically a slow ...
Context.The search for active longitudes on the Sun has a long history, and many controversial resu...
International audienceVarious manifestations of solar activity are not uniformly distributed with he...
Context.It has recently been claimed that analysis of Greenwich sunspot data over 120 years reveals...
Abstract In this thesis solar active longitudes of X-ray flares and sunspots are studied. The fact t...
As recently found, the distribution of sunspots is non-axisymmetric and spot group formation implie...
A novel analysis of sunspot group data for the past 120 years reveals that sunspots in both northern...
Abstract. As recently found, the distribution of sunspots is non-axisymmetric and spot group formati...
We present an overview of the observational results related to the existence of long-lived sunspot a...
Context. The sunspots and other solar activity indicators tend to cluster on the surface of the Sun...
Context.Recently, it was found that two persistent active longitudes of sunspots separated by about...
Context. After considering the solar surface differential rotation, it was found that two persistent...
The modulation of solar activity closely follows the solar rotation period suggesting the existence ...
All A&A articles are in open access ONE year after their publication date (August 2013)Aims. The lat...
Context. Solar active longitudes and their rotation have been studied for a long time usin...
Sunspots have been observed to undergo rotation about their umbral centre. This is typically a slow ...
Context.The search for active longitudes on the Sun has a long history, and many controversial resu...
International audienceVarious manifestations of solar activity are not uniformly distributed with he...