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End of July 2022 the founder and manager of, Eric Frappa, informed the European community of occultation observers about the end of his service by 2022 December 31. So Eric Frappa took care for all observations made until end of 2022 and send the reductions in the common way. IOTA/ES will take care of the data collection in a new portal named SODIS in 2023 and further on.

IOTA/ES starts SODIS (Stellar Occultation Data Input System) as a system to collect the observation results of the European observers. In the web based system SODIS, observers can collect and report all observations, also the negative results. During the development of SODIS it had to be considered that data collection, reviewing and reporting have the highest priority. Other functions, like comparisation chords versus modelation of minor planets will be possible, but have not yet been realised.

Unregistered users can see all observations collected in the system of SODIS. You can reach this sub-domain via the webpage of IOTA/ES. In this window the user can see all observations in the database. On the upper part users see some statistic and can search for different criteria (star, planet, observer, country etc.). The search area is the top part of the start screen, the database is visible after a scroll down.

The ever-increasing accuracy of astrometry of stars and minor planets has expanded the possibilities for observing stellar occultations in recent years. Whether distant TNOs, near-Earth objects, comets, main-belt asteroids or future targets of space probe missions, our observing tasks are diverse and will still increase in number. Therefore, it is necessary to gradually automate the collection of observational data in Europe and to distribute the review of these data among several shoulders. Observations of stellar occultations with only negative chords will also be stored in the new database for possible future evaluations. No observation should have been carried out in vain any more. In order to lead this project successfully into the future, your cooperation is needed. Report your observations on your own into SODIS by creating an account. Please submit your data completely to keep the workload of the reviewers on a low level. The SODIS team is looking forward to your cooperation, criticism and suggestions. Especially additional local reviewers for European countries not yet covered are welcome.

If you can provide support and want to join the team, please contact us via

You can find more information in our Journal for Occultation Astronomy (JOA) issue 2023-1.