Multi-purpose expedition of representatives of the Slovak Astronomical Society at the Slovak Academy of Sciences and the Slovak Union of Astronomers to southern Spain.
The expedition was attended by Pavol A. Dubovský, chairman of the Variable Stars and Exoplanets Section, and Mgr. Karol Petrík, coordinator of the Astronomical Photography Section. The expedition itself also consisted of two interconnected parts. From October 6 to 9, 2025, the participants attended the ASTROROB25 workshop on robotic telescopes (https://astrorob.com/), held in Almería. Although the workshop continued for two more days, our expedition moved inland to the locality of Piconcillo – the future hosting site for remotely operated telescopes of Slovak astronomers. The following summarizes the main observations, outputs, and results of this journey.
ASTROROB25
The workshop has already reached its eighth edition and is organized every two years. Several institutions participate in its organization, most notably the Instituto de Astrofísica de Andalucía (Andalusian Institute of Astrophysics). The scientific organizing committee included prominent personalities from around the world. The participant roster was equally diverse, with all continents except Antarctica represented.
The scientific focus of the presentations was also very broad, as can be seen from the workshop program available on the above-mentioned website. If we were to determine where robotic telescopes provide the greatest benefit, it would clearly be in fields requiring rapid response to transient phenomena, such as gamma-ray bursts, supernovae, kilonovae, compact object mergers, gravitational-wave detections, and similar events. Abstracts of individual contributions have also been published for more serious readers.
We presented posters titled: “Appearance of optical QPO with time scale of 3800 s after outburst of nova V1405 Cas” and “Search for Nova Super-remnants Campaign Conducted by Amateur Telescopes in Automated Operation”. The conference proceedings will be published in Revista Mexicana de Astronomía. In the case of the article about the search for nova super-remnants, this represents a way to publish the campaign’s “white paper,” which future publications of campaign results will be able to reference. An electronic version of the posters is available here: https://var.kozmos.sk/2025/10/15/posters-exposed-at-the-astrorob25-workshop/. Slovakia was also represented by the Astronomical Institute in the person of Ján Adamčák.
In the presentation about searching for nova super-remnants, we emphasized the need for a very large amount of observing time, which is unattainable under Central European conditions. Solving this problem was the focus of the second part of the expedition. Before moving on to that, here are several of the most interesting observations from the workshop:
- Winner Observatory telescope hosting in the USA – although operated by a non-profit organization – is significantly more expensive than European hosting facilities. Their cable carriers for moving cables are the same type as those used in Kolonica, only more robust.
- In Kazakhstan, seven telescopes were built in four years. The entire observatory is powered by solar energy – 12 panels rated at 400W and 16 batteries with a capacity of 200Ah.
- Several interesting software products were presented: PyObs, Twincat 3, DRACOS (observatory control system at Montsec in Catalonia), MIRA (an interface for providing observing time), and STDpipe – a Simple Transient Detection Pipeline for transient detection.
- Several interesting hardware solutions were also presented: Beckhoff PLC systems, automatic door closing for a roll-off roof observatory in Zurich, and quantitative CMOS detectors – qCMOS.
- Potential clients for the telescope hosting project were identified: the GOTO and MASTER networks, as well as individual users.
- During informal discussions, for example with Jasem Mutlaq (INDI drivers), we discussed field derotation on alt-azimuth mounts using the Esatto Arco derotator.
- Together with Martin Jelínek (Astronomical Institute of the Czech Academy of Sciences), we discussed how to properly perform flat-field correction when brightness differences at the level of 1 ADU are important. This has a serious implication for our astrophotography campaign: truly reliable calibration frames can only be obtained during the same night and very close to the target observation field. A synthetic flat must then be generated from these images.
- An interesting meeting also took place between three people who are launching ambitious projects at almost the same time. Their budgets differ, but they share a belief in success. See Fig. 1.
The workshop featured an exceptionally rich social program, during which we also visited the Calar Alto Observatory.
A one-sentence conclusion: The community of robotic telescope operators is ready for the avalanche of data from the Vera Rubin Telescope.
PICONCILLO
The village, with a population of 42, already has two astronomical domes, a third is being prepared, and we plan to establish a new telescope hosting facility there. It holds a Starlight Destination certificate, has a viewing terrace for astronomical observations, and a local astronomy organization that arranges public events. Is it truly a paradise for astronomers? Is it the right place for the telescopes of our astrophotography campaign? That is what we set out to investigate.
Some information was already available. An article about the first expedition to Andalusia has already been published on the astrophotography campaign website https://astrophoto.kozmos.sk/andaluzia/. The main goal was to secure land where the telescope pavilions could be built. Significant progress has indeed been made in this regard. A suitable plot of land is available, and discussions are now essentially focused only on the price. An important role was played by local supporters who became enthusiastic about the idea of telescope hosting in Piconcillo and provided broad assistance. These are the owners of the two observatories in the village: Hubert Delaunay and Francisco Manuel Santos.
We also surveyed other locations. However, according to the established criteria (described in the article about the first expedition), Piconcillo still appears to be the optimal site. For the purposes of the astrophotography campaign, the key parameter is the number of clear nights. In Andalusia, this generally ranges between 260 and 280 nights per year. When combined with the fact that summer nights are considerably longer than in Slovakia, this results in up to four times more observing time compared to Kolonica, for example.
To obtain specific data directly from the site, we installed an all-sky camera next to Hubert’s dome. The data are available at www.bombol.space/allsky-piconcillo.
A second comparison is based on panoramic night images documenting sources of light pollution above the horizon. Here as well, Piconcillo performs satisfactorily.
The survey conclusions are summarized in Table 1.
| Criterion | Weight | Rating | Points | |
|---|---|---|---|---|
| 1 | Dark sky (Bortle 2) | 15 | 0.8 | 12 |
| 2 | Number of clear nights (250) | 30 | 0.7 | 21 |
| 3 | Latitude between 28° and 50° (38°) | 10 | 0.6 | 6 |
| 4 | Seeing (2”) | 10 | 0.8 | 8 |
| 5 | Climate pleasant for on-site operation | 5 | 0.8 | 4 |
| 6 | Transport accessibility | 5 | 0.4 | 2 |
| 7 | Internet availability (Starlink or optical cable within 500 m) | 5 | 0.6 | 3 |
| 8 | Availability of electricity and water | 5 | 0.6 | 3 |
| 9 | Local support | 10 | 0.9 | 9 |
| 10 | Accommodation and permanent living possibilities | 5 | 1 | 5 |
| Overall (maximum 100 points) | 73 |
The expedition was carried out with financial support from the Slovak Union of Astronomers and the M. R. Štefánik Observatory and Planetarium in Hlohovec.
Recorded by Pavol A. Dubovský, Chairman of the Variable Stars and Exoplanets Section of the Slovak Astronomical Society at the Slovak Academy of Sciences and the Slovak Union of Astronomers.
Photographs by the author and Karol Petrík.