Sunspot tracking using ImageJ and Python

(supervisor: Dave Langstaff)

Nature of project: data analysis, software

Available to full-time physicists or joint students.

Project description and methodology

Sunspots are windows for us through which we can have a two-dimensional glance into the complexity of the solar magnetic structure. Discovering their behaviour is a key element of understanding the physics of the Sun itself. The project aims at building up a program code, written in ImageJ/FIJI, Python or any other suitable package, which is capable of reading image files created from SOHO/MDI continuum (optical) data files and tracking selected sunspots while they are visible in the solar disc.

It may be that the optimum approach will be to use ImageJ (or FIJI) to explore and optimise the processing steps required before coding these into Python using a suitable image processing library.

A successful project will develop beyond the above in one/some of the following directions:
It is envisaged that a simple approach will be taken to produce scripts to run on ImageJ/FIJI to produce co-ordinates of sunspots in solar latitude and longitude. A suitable development would be to interface these results with a tracking routine to produce tracks showing movement of particular sunspots over time.

When considering where to take your project, please bear in mind the time available. It is preferable to do fewer things well than to try many and not get conclusive results on any of them. However, sometimes it is useful to have a couple of strands of investigation in parallel to work on in case delays occur.

This project is only available as a Y3 project.

Initial literature for students:

  1. Module PH38720 (Sun and Heliosphere)
  2. Phillips, K.J.H., 1992, Guide to the Sun, Cambridge [QB 521 P5] {Section 6.1, p.168-181}
  3. Hathaway, D.H., Choudhary, D.P., 2008, Sunspot Group Decay, Solar Physics (Online First)
  4. Ferreira, T. and W. Rasband (2012). ImageJ User Guide, Online

Novelty, degree of difficulty and amount of assistance required

Studying of sunspots is obviously not a new idea, as they have been intensively observed and analysed since the 17th century. However, the fact that the worldwide solar research community is astonished by the current behaviour of the Sun clearly shows that our knowledge of our star is far from complete. The program to be written in the project will make it possible to do extensive statistical analysis on sunspot data.The student will gain experience of a comprehensive data analysis. The data sets and a software package (SolarSoftWare, SSW) to handle the data files are available via the web. The procedure of finding, downloading, converting and processing data files from solar observations will have to be learnt. The data processing will require computational skills and use of the ImageJ package as well as Python programming and use of an appropriate image processing library.

Project milestones and deliverables (including timescale)

milestoneto be completed by
Learning the physics of sunspotsend of October
Fiji/ImageJ script to detect sunspotsChristmas
Convert application to Pythonend of February
Track sunspot movementEaster