Ursa Astronomical Association

History of Ursa

Tähtitieteellinen yhdistys Ursa (Ursa Astronomical Association) was founded in 1921 by Yrjö Väisälä and several other young scientists. Five years later Ursa established an observatory in southern Helsinki (Kaivopuisto Park). Activities included public lectures on astronomy and related sciences. In the 1930s Ursa released two films dealing with astronomy and the theory of relativity. In the late 1960s Ursa obtained a small room from the City of Helsinki which was used mainly as a library and was open twice a week.

From the 1930s to the 1960s several members of Ursa erdited books published by a large commercial publishing house. In 1975 Ursa published its first book. Nowadays Ursa is the most notable astronomy book publisher in Finland.

Ursa´s membership journal Tähtiaika was first published in 1971, and it was renamed Tähdet ja avaruus in 1976. The journal got its first full time employer in 1998 and it was renewed into modern astronomy magazine. Nowadays Tähdet ja avaruus has a staff of four, circulation of 17 500 and about 70 000 readers.

Ursa's primary functions are to advance astronomical education and to promote interest in astronomy. New activities include courses on astronomy, as well as astronomical camps and clubs for children and adults. Since 1984 planetarium presentations have been conducted with a portable planetarium. Ursa currently has over 15 000 members.

The Ursa Office

The Ursa office in Helsinki is located at Helsinki Observatory, 2nd floor. The office is open Monday through Friday (except holidays) from 9 AM to 4 PM (9 AM to 3 PM in July). Visitors are encouraged to drop by and meet the staff. Books and other items published by Ursa are available for purchase. The staff can also be reached by telephone (int. +358 9 684 0400, dom. (09) 684 0400), e-mail ursa(a)ursa.fi, or regular mail (Ursa Astronomical Association, Kopernikuksentie 1, FIN-00130 Helsinki, Finland). Large numbers of books and magazines are mailed annually.

History and Services of the Ursa Library

The Ursa Library was founded in the mid-1920s. For a long time the library had less than a hundred books. The number of items began to grow in the early 1980s. Members can borrow books, offprints, slide sets, video films and audiotapes by visiting the library in person or sending their orders via mail. The current library collection consists of nearly 6000 items in about 20 languages. About 3500 are books, excluding bound volumes of magazines. The majority of items are in English, Finnish, German or Swedish. A catalog of items is available either in printed or electronic form. Since late 1997 the catalog has been available for browsing from the Ursa web site. Members and other users of the Ursa Library borrow over 1000 items annually.

Ursa Observatory

The Ursa Observatory is in Kaivopuisto Park in Helsinki. There are now three telescopes. A very old Merz refractor was bought in 1928 (aperture 135 mm, focal length 1950 mm), and is still in excellent condition. A 25-cm Ritchie-Chretien reflector shares the mounting with the Merz-refractor. A fairly new Celestron 8 telescope is on a separate mounting. The observatory has a small warm room that has enough space for four or five persons. The Merz-refractor can be used with a narrow wavelength Hydrogen-alpha filter. Nonmembers can visit the observatory during autumn and spring evenings to look at the starry sky, and during the day on summer weekends to observe solar phenomena through filters. Interested members can use the observatory on Mondays and times outside of star shows.

Public shows are (clear weather only):
15 Oct-15 Dec: Tue-Sun at 7 to 9 PM
15 Jan-15 Mar: Tue-Sun at 7 to 9 PM
15 Mar-15 Jun: Sun at 1 to 3 PM
1 Aug-30 Sep: Sun at 1 to 3 PM

Fees:
3,00 EUR adults, 1,50 EUR children

Planetarium

Ursa members first designed and developed a portable planetarium in 1984. Its plastic dome is six meters in diameter and over four meters high, and it can accommodate about 20 people during presentations. Two kinds of projectors are available: they can present the starry sky, Sun, Moon, planets and twilight. Slides can also be projected onto the dome. The planetarium has been exhibited at fairs, and many schools in southern Finland have used the planetarium for an entire day or more. Ursa also has two Star Lab planetariums available for schools to rent at a modest cost.

Lectures, Courses and Happenings

The work of Ursa has included public lectures for several decades. From September to May, monthly lectures are open for anyone interested. There are no fees. Lecturers include both professional astronomers and experienced amateurs. Topics include the results of new studies, fundamentals of astronomy, or current events in the sky. Ursa also arranges several courses annually on evenings or weekends. One of the most popular courses discusses how to use telescopes.

Ursa cooperates with local (independent) astronomical associations each year during Astronomy Weekend. The first Astronomy Weekend was held in Turku in 1971. More recently, the 26th Astronomy Weekend was held in Lahti March 1998 and 27th Astronomy Weekend in Järvenpää in 2000. About Active amateurs come to these happenings year after year. The program consists of lectures, amateurs' meetings, and exhibitions of astronomical instruments and the results of their observations.

Since 1987, Cygnus Summer Meetings have been held each year for active amateurs. This is generally a four-day long event, and includes meetings of Ursa sections, photo contests, discussions, observations, and telescope making.

For several years the Astronomy Day in winter or autumn has also been held, when many associations arrange astronomical programs for less-experienced amateurs and other interested persons. These events include lectures, exhibitions, slide and video shows, star shows without fees, etc. Ursa maintains contact with all amateurs' associations in Finland. A database of associations is updated frequently.

Activities for Young People

Many of Ursa's 15 000 members are young people. There has been an annual astronomical youth camp near Metsähovi Observatory since 1984 till late 1990's, after that somewhere near Helsinki area. These camps have been scheduled in the beginning of August when the air is still warm at night and the sky is fairly dark. About 30 children age 8 to 17 years attend these camps. Experienced amateurs serve as guides for the participants.

Activities for young persons are not limited to camps. Three clubs for young amateurs gather every week at the Ursa Library during winter. They become acquainted with astronomy and observing with the help of experiments, slides, video films and laser disks. They can also visit Ursa's planetarium and observatory. These clubs were named after three stars in the constellation Orion. The least experienced club was named after the star Meissa (Lambda Orionis). The next club was named after Rigel. The most experienced group was named after Betelgeuse. Nowadays the children and teenagers have a club room at Castreninkatu 8, Helsinki.

Publishing

Ursa publishes popular astronomy magazine Tähdet ja avaruus, a bulletin for observing sections, slidesets, and an astronomical yearbook. In addition, about 70 books had been published as of the beginning of 2000. Ursa publishes frequent press releases for newspapers, magazines, television, radio, etc. Photographs from Ursa's photo archive are rented quite often. Ursa has also developed several computer programs to explain astronomical phenomena.

Sections and working groups

There is so much to observe that it is not possible for one person to effectively observe all kinds of phenomena. Ursa has 15 observing and technical sections and working groups: The Sun, Atmospheric Optical Phenomena, Club Activities, Moon, Planets and Comets, Mathematics and Information Technology, Meteors, Fireball Working Group, Variable Stars, Optics and Telescope-making, Minor Planets and Occultations, Aurorae, Deep Sky, Weather and Observing Conditions, Satellites and Rocket Phenomena, and Astrophotography. All sections help to coordinate the work of amateurs, giving advice and collecting observations. Sections also interact with each other and have cooperating activities. The most important form of cooperative activities is the Cygnus summer meeting.

Ursa Minor Newsletter

The newsletter Ursa Minor is a media where all sections report the results of their observations and news about current projects. It is published six times a year. Each section has its own column. There are also common pages for general news and a calendar of observations. Ursa Minor will be sent without charge to active members of sections. Others can order it for a small fee.