Tähtitieteellinen yhdistys Ursa
The Finnish Deep Sky group is one of the activity groups of the nationwide Ursa Astronomical Association. The aim of the group is to act as a link between Finnish deep sky observers and to share knowledge on different aspects related to observing. Established by Risto Heikkilä, the group has been operational since 1985 and is currently led by Toni Veikkolainen, assisted by Juha Ojanperä, Rauno Päivinen, and Jari Saukkonen.
Since 2003, the group has maintained Deep Sky Archive, which is used for uploading and storing deep sky observation sketches. The language of the user interface of the system is English. Currently the system hosts more than 7000 observations from Finland and other countries altogether. Uploading new observations to the archive has been disabled but old observations can be searched.
Since its introduction in 2011, the Taivaanvahti system of Ursa has been available for submission of photographic and visual deep sky observations. The system is available in Finnish, Swedish, and English. When the publication of observations from abroad is considered, particular importance is given to those on objects not visible from Finland.
An annual meeting is one of the longstanding institutions of the group. The first meeting took place in 1994 at the summerplace of Jere Kahanpää. Since 2006, the meeting has been arranged in the Tähtikallio observation centre, Orimattila, Finland. Interested amateur astronomers are welcome to attend the meeting that will take place next time from September 6 to 8, 2024.
In addition to the traditional deep sky catalogues available on various websites, several other ones can be accessed via the site of the group. The language of these catalogues is English.
- Herschel 400 North - A revised edition of William Herschel's (1738-1822) catalogue of 400 deep sky objects. All objects not visible or poorly visible in Finland have been excluded and replaced by more northerly ones.
- Deep Sky Section 600 - A general catalogue of deep sky objects, gathered with the users of small and moderate-size telescopes in mind. Including objects down to the declination of -50°, the catalogue is useful for observers across European latitudes.
- Lord Rosse 85 - The catalogue of "spiral nebulae" originally gathered by William Parsons (1800-1867). The object types have been updated to match the contemporary definitions.
- Ursa Naked Eye Catalogue - A catalogue of deep sky objects observable with the unaided eye. Both the northern and the southern hemisphere are included, albeit the information on far southern objects may in some cases be incomplete.
Other English-language resources on the website of the group include:
- Deep Sky in the Seventh Heaven - An article by Timo Karhula on deep sky observing in Australia.
- The Mystery of M57 - A brief introduction to the mysterious extra star in the Ring Nebula.
- Abell Planetaries - Observations on George Abell's catalogue of planetery nebulae, gathered during an observing campaign of the group.
- Objects in M33 - Observation on objects within the Triangulum Galaxy, gathered during an observing campaign of the group.
- Syksyn syvä taivas 22.9.2023
- Syvä taivas -tapaaminen 2023 19.9.2023
- Syvä taivas -tapaaminen 2022 15.9.2022
- Syvä taivas -tapaaminen 2021 Tähtikalliolla 24.9.2021
- Syvä taivas -tapaaminen 2020 6.10.2020
- Kokemuksia eteläisen tähtitaivaan kuvaamisesta Chilessä 28.2.2020
- Australian tähtimatka elokuussa 2019 19.12.2019
- Supergalaktisen tason dynamiikan simulaatio saattoi ratkaista arvoituksen 21.11.2023
- Vs: IC 1805 Sydänsumu 12.11.2023
- Vs: IC 1805 Sydänsumu 12.11.2023
- Vs: M8 ja M20 - Laguuni ja Trifid 8.11.2023
- Vs: IC 1805 Sydänsumu 7.11.2023
- Vs: NGC 6914, heijastussumu Joutsenessa 1.11.2023
- Vs: Sh2-240, supernovajäännös 24.10.2023
- Vs: NGC 6960 Harsosumu 24.10.2023
- Vs: NGC 2070 - Lintuhämähäkkisumu alias Tarantula Nebula 24.10.2023
- Vs: IC 434 Hevosenpääsumu 23.10.2023