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Solar Feature Catalogues

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May 2005
New MSc degree in Intelligent Data Mining at Cybernetics department, Bradford University starts from September 2005. For the inquiries please contact Recruitment Office in Horton A1.09.

May 2005
Present 1 oral talk on the solar activity in the cycle 23 at the Assembly of the American Geophysical Union - Solar Division Meeting, 26 May 2005, New Orleans, US.

April 2005
The EGSO Solar Feature Catalogue (SFC) is now available for experimentation here.

March 2005
Presented 1 oral talk on sunspot statistics, two posters on active region statistics and general EGSO project at European Geophysical Union Assembly, Vienna, Austria

February 2005
4 Papers based on results obtained from EGSO SFC are accepted for publication in Solar Physics Frontiers in Image Processing Special Issues

January 2005
Started work on generating Active Region/Plage data from Meudon Halpha observations. Data will be available by June 2005.


EGSO, the "European Grid of Solar Observations", is a Grid test-bed that will lay the foundations of a "Virtual Solar Observatory".

With a substantial increase in size of solar image data sets, the automated detection and verification of various features of interest is becoming increasingly important for, among other applications, the reliable forecast of the solar activity and space weather and data mining. However, this raises the accuracy and reliability requirements to the detection techniques applied for an automated recognition that have to be significantly improved in comparison with the existing manual ones. One of the chief objectives for European Grid of Solar Observations (EGSO) Project Work Package 5 was a production of Solar Feature Catalogues by means of the automated feature recognition methods.

Amongst such features of interest are sunspots, active regions and filaments (see the paper by Zharkova et al, 2005, 'Solar Feature Catalogues in EGSO', Solar Phys., 228, 361

There is a growing number of archives of digitized images of the Sun, taken from ground-based and space in-struments in various wavelengths. These archives are available from different locations and are to be included into a unified catalogue by the European Grid for Solar Observations (EGSO) project (Bentley, 2002)

Digitized solar images from different sources have a variety of sizes, resolutions, dynamic ranges and instrumental and weather associated distortions. All are to be subjected to automated recognition processes in order to provide reliable data on the locations of features and their evolution at different times relative to solar rotation. This is aimed partly at the growing demand for solar activity forecasts by the space weather project and by many industrial organizations, which have a great need for the development of reliable and fast techniques for feature recognition on solar disks and their presentation in Solar Feature Catalogues.

These catalogues are intended to contain comprehensive statistics of active events (sunspots, active regions, filaments, flares, etc.), overlapping in a given period of time and to allow the extraction of physical characteristics, which are essential for the solar activity forecast. This requires designing advanced image recognition techniques in order to identify individual features (sunspots, active regions, filaments, magnetic neutral lines, etc.) on the images with strongly varying background caused by different terrestrial atmosphere observing conditions of solar atmosphere activity period, irregularities in shape caused by instrumental errors or any other noise in images like strips or signatures etc. For added reliability, these algorithms have to use cross-referenced criteria at multiple wavelengths in order to correctly identify the features of interest while fully utilizing all the datasets linked into the Grid.

The following papers describe some of the feature recognition techniques: Zharkova et al., 2003, Solar Phys.,214,89; Zharkova et al., 2005, Solar Phys., 228, 361, which have been developed for the automated detection of the selected solar features: sunspots, active regions, filaments and magnetic inversion lines.

EGSO is funded under the Information Society Technologies (IST) thematic programme of the European Commission's Fifth Framework Programme. The project is one of many partners from across Europe that co-operate through the EU GRIDSTART initiative. EGSO is also working closely with the US VSO project, funded by NASA.