Solar Weather Browser

Welcome at the Solar Weather Browser (SWB) download and user support web page.

Thank you for your continued interest in SWB! Please stay tuned for new developments soon, including awesome images from our SWAP EUV telescope.

Table of contents:


The Solar Weather Browser (SWB) is a software tool developed by the Royal Observatory of Belgium for easy visualisation of solar images in combination with any context information that can be overlaid on the images and that is space weather relevant. In Fig. 1, two examples are shown of two interactively choosen combinations of data. On the left, a combination of an EIT/19.5 nm image with an overlay of CME detections by CACTus. On the right, a combination of an EIT/17.1 nm image with a 14 degrees grid and NOAA active region numbers.

Fig. 1. Screen-shots of the SWB.
In the current SWB version, you can easily browse the image sequences using the Left/Right keys of your keyboard.
If several overlays of a certain type are available, the closest in time will be automatically matched to the current image.
Pressing the Home/End keys will bring up the first/last image of the day.
Pressing the Up/Down keys will move one day backward/forward.
Pressing the PageUp/PageDown keys will move 27 days backward/forward.
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The Solar Weather Browser client software is Copyright © 2004–2011 Royal Observatory of Belgium and was written by Bogdan Nicula (email: first name.last name at oma dot be).

It is licensed to you under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. Please note that this software comes with absolutely no warranty and the SIDC is unable at this time to provide any kind of support for it.

For your convenience, the software is also packaged in compiled binary form for certain versions of Microsoft Windows and Apple Mac OS X operating systems. Those packages contain some software libraries in compiled binary form that are copyrighted by their respective authors and are covered by their own license terms.

You can download the software below. Take care to preserve the original file when downloading. Some web browsers may try to uncompress it on the fly and/or change the (extension of the) filename.


Microsoft Windows users Apple Mac OS X users Source code (Unix users) [back to top]


  1. The drop down menus "Image" and "Overlay" are empty.
    - Check if your computer is connected to the network.
    - Check if your firewall settings allow the SWB to connect to the internet, it needs http access to the SIDC website.
    - Check if the date that you are requesting is after April 1, 2004.
  2. I am using Windows 98 and the SWB is not working.
    - You may need to start the SWB from the command prompt.
    - The development version and the next version (1.2) will run only on Windows 2000 or later.
  3. I am using Mac OS X and the SWB is not working.
    - Check console.log using /Applications/Utilities/Console. If you find a message similar to:
     No fonts found; this probably means that the fontconfig
     library is not correctly configured. You may need to
     edit the fonts.conf configuration file. More information
     about fontconfig can be found in the fontconfig(3) manual
     page and on http://fontconfig.org.
    you may have an obsolete '/etc/fonts/fonts.conf' file which was not properly upgraded from previous operating systems. Please use the development version, it contains a workaround.
  4. It still doesn't work / I cannot figure it out.
    - Please contact the author.
    - Send an e-mail to: SWB at sidc dot be
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The SWB consists of 2 parts: (1) the SWB backend server and (2) the SWB user interface.

The backend server collects data from a variety of sources using different protocols. After acquiring the data, the backend server preprocesses the different types of data with specialised software and makes them available on the distribution website. In this way, the user does not need detailed information on the location and accessibility of the data, nor on specialised software required to run the data. The splitting of the SWB in a user interface and a backend server has the additional advantage that new types of data can be included without the need to re-distribute the user interface.

The SWB backend server

The backend server of the SWB runs on a Linux machine as a cron job that regularly (4 times per day) triggers a shell script. The shell script executes sequentially a series of dedicated instrument programs. Extensive use is made of the "Solar Soft Library".

Fig. 2. Overview of the working of the SWB-server. Data are gathered from different sources (yellow) using different protocols. Both images and context information are gathered into zip archives (blue) and stored on a distribution website (green). This distribution website is consulted by the user interface in a way transparent to the user.

The output of the server is stored on a website (http://sidc.be/SWBS). The images are highly compressed and ordered chronologically.

Some examples of background images produced:

Note that, since these images are made available fully automatically in near-real time, occasional corrupted images or images of degraded quality cannot be avoided.

Some examples of overlay images produced:

Not all the data are available every day (e.g. EIT bake out periods or bad weather conditions in Catania). The availability of images is specified in an index file. The information in the index file is read by the SWB client and used to fill the drop-down menus 'Image Control' and 'Overlay Control' (see Fig. 3).

The SWB user interface

[ The description below was written for SWB version 1. The upcoming SWB version 1.2 will have a slightly different user interface, but most of details will remain the same. ]

The user interface source code of the Solar Weather Browser is written in C in a cross-platform manner and runs on Microsoft Windows and any UNIX-like operating system for which the GIMP toolkit version 2.2 or later is available (including Mac OS X).

Here is an image of a Solar Weather Browser window with its main elements highlighted:

Fig. 3. Screen shot of the SWB showing a SOHO/EIT image overlaid with CACTus CME detections.

The normal operation of the program involves network access to the SIDC website. There are two types of network operations, both cached:

The current day as indicated by the user's computer clock is automatically selected at program startup. The image and overlay types lists are built from the information retrieved from the server. Operating the calendar control will fetch automatically the list for the selected day and will try to display if possible the previously selected image combination.

After selection of an image type using the image control menu, the available images list can be traversed using the navigation control buttons. The message area displays the image number in the sequence, while the acquisition time is displayed under the image control.

As many as two overlays can be super-imposed using the overlay control menus.

The images can be rescaled by using the zoom control buttons or by window resizing. The rescaling operation always preserves a 1:1 aspect ratio.

The image area can be detached from the main window by dragging it out using the detaching handle. It can be re-attached by dragging it back or by double-clicking the handle.

The display of the image area, including the overlays, can be saved selecting "Save As" in the "File" menu. The saved file is always a non-scaled PNG image.

Since the images on the server are generated in near real-time, the current day list of available images can be re-fetched from the server using "Refresh Day" in the "File" menu.

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The SOTERIA project in general, and the present tool in particular (deliverable 6.7), thankfully acknowledge support from ... .
... from the EU Framework 7 Programme
The SWB is maintained by the Solar Terresterial Center of Excellence at the Royal Observatory of Belgium.
An early version of the SWB was co-funded by ESA (16913/03/NL/LvH).

All trademarks used are properties of their respective owners.

Last modified by Bogdan Nicula on Sep 27, 2011.