Skip to main content

Who can contribute as an observer to the SILSO sunspot network?

Anyone can become member of our world wide observing network. We have both professional observatories(~30%) and amateur astronomers (~70%), from more than 30 different countries. As our current network is rather concentrated in Europe, we are particularly happy to welcome observers from other continents and latitudes.

There are only a few base requirements:
- a telescope equipped for solar observing (eyepiece observations with proper solar filter or prejection on a screen) with an aperture of min. 50 mm.
- dedication: observers are expected to provide observations on about 10 days per month on average and to be committed to observe for at least several years once they register in the network.
- good consistency: stable observing practices, good observing skills.

We don't impose specific technical rules regarding the observing equipment and counting method. In case of doubts, we can of course provide guidance and advices. However, we consider more important to let each observer choosing her/his preferred observing method and then naturally sticking to it (long term stability!) than to impose a common well-coded method requiring a personal adaptation of the observer. Indeed, it introduces a risk that after some time, the observers drift away from this imposed standard, spoiling the long-term stability, or that the observers become discouraged and quit because some rules prove too awkward in their local observing context.

Interested to join? In order to get your station number, be registered in our network and have access to your personal data input Web page, just send us an e-mail. We will provide you the instructions to get you started.

BACK