3 The samples and distributions

We have investigated the distributions of foundation years for the categories as described hereafter. The general characteristics are summarized in Table 1 which gives also a weighted average and the corresponding dispersion for each sample.

A specific organization may belong to several categories (typically a public observatory may also host a planetarium and vice versa a planetarium may offer observing facilities to the public). On the other hand, when an organization (typically a commercial company) had several branches at different locations registered with the same foundation year, it counted only for one single occurrence in the statistics. This applied also to large scientific institutions with several entries (divisions, departments, and so on) in the database.

When the worldwide sample was large enough (total sample, institutions, associations), we additionally considered two geographical subsamples: on one hand, a "North American'' one made of entries from Canada plus U.S.A. and, on the other hand, a "West European'' one consisting basically of all the countries from the European Union, plus Iceland, Norway and Switzerland. As seen from Table 1, such grouping gives samples of similar sizes in two cases out of three (and thus the results of these are directly comparable). There is no special discrimination in leaving out the East European countries (former Socialist Republics): simply those countries have not yet completed their restructuring following the fall of the iron curtain as we experience it daily when updating the databases. Also the obtention of reliable and exhaustive data still remains a problem as of today in some of these countries.

Cumulative distribution curves have been used for a better legibility of the significant events. The scale of the abcissa (time/years) has also been chosen for the best legibility of the curves. The ordinate scale has been automatically adapted to the sample size. In any case, additional plots can be requested from the author.

Surges or ruptures of the slope gradient are interesting features as well as plateaux in the otherwise always increasing cumulative curves. A priori, the following periods of time should be perused: World War I (1914-1918), World War II (1939-1945), the launch of Sputnik I (1957) and the landing on the Moon of Apollo 11 (1969), especially for the organizations linked to the public and/or amateurs.

The flattening of the curves towards the end of the ranges is considered as non-significant and attributed to the fact that the most recently created organizations might not be registered yet at the time of writing (Fall 1998). End-of-Cold-War effects are however not excluded.

3.1 Total sample

The cumulative distributions for the total sample are illustrated in Figs. 4 to 6 (World, Western Europe, Canada + U.S.A.) from 1900 onwards.

The effect of WWI is noticeable on the West European curve, while the impact of WWII is clearly visible on all curves. A surge at the end of the fifties is striking on the North American curve which is much steeper from then on. The effect is smoother on the West European curve, but the change of steepness is definitely there too. Let us try to identify more precisely those effects in the following subsections.

 

Figure 4: Cumulative distribution of foundation years for the whole sample (all categories, all countries - see text and Table 1)

 

Figure 5: Cumulative distribution of foundation years for the whole sample (all categories, Western Europe - see text and Table 1)

 

Figure 6: Cumulative distribution of foundation years for the whole sample (all categories, Canada + U.S.A. - see text and Table 1)

 

Figure 7: Cumulative distribution of foundation years for the astronomy-related academic institutions (all countries - see text and Table 1)

 

Figure 8: Cumulative distribution of foundation years for the astronomy-related academic institutions (Western Europe - see text and Table 1)

 

Figure 9: Cumulative distribution of foundation years for the astronomy-related academic institutions (Canada + U.S.A. - see text and Table 1)

 

Figure 10: Cumulative distribution of foundation years for the astronomical associations (all countries - see text and Table 1)

 

Figure 11: Cumulative distribution of foundation years for the astronomical associations (Western Europe - see text and Table 1)

 

Figure 12: Cumulative distribution of foundation years for the astronomical associations (Canada + U.S.A. - see text and Table 1)

 

Figure 13: Cumulative distribution of foundation years for the planetariums (all countries - see text and Table 1)

 

Figure 14: Cumulative distribution of foundation years for the public observatories (all countries - see text and Table 1)

 

Figure 15: Cumulative distribution of foundation years for the publishers (all countries - see text and Table 1)

 

Figure 16: Cumulative distribution of foundation years for the software producers (all countries - see text and Table 1)

3.2 Professional institutions

The cumulative distributions for the academic institutions who clearly indicated an astronomy research/education activity are illustrated in Figs. 7 to 9 (World, Western Europe, Canada + U.S.A.) from 1900 onwards.

Among the oldest institutions, let us mention here: Beijing Astronomical Observatory (1279), Leiden University Observatory (1633), Utrecht University Observatory (1642), Uppsala University Observatory (1650), Paris Observatory (1667), Lund University Observatory (1672), Royal Greenwich Observatory (1675 - but being shut down at the time of writing), and Astronomisches Rechen-Institut (1700).

All the curves display a slow slope increase as time goes with a clear acceleration in the mid-sixties in Europe (the "golden sixties'') and at the end of the fifties in North America. In the mid-seventies, the slopes subside until another surge in the mid-eighties.

3.3 Associations

The cumulative distributions for the associations who clearly indicated an activity in astronomy is illustrated in Figs. 10 to 12 (World, Western Europe, Canada + U.S.A.) from 1900 onwards.

Here are the major associations founded last century and still active today: Royal Astronomical Society (1820), Chicago Astronomical Society (1862), Astronomische Gesellschaft (1863), Liverpool Astronomical Society (1881), Baltimore Astronomical Society (1881), Société Astronomique de France (1887), Astronomical Society of the Pacific (1889), Royal Astronomical Society of Canada (1890), British Astronomical Association (1890), Astronomical Society of South Africa (1892), Astronomical Society of Glasgow (1894), and American Astronomical Society (1899).

The curves display slight flattenings at the level of WWI and WWII. The West European curve is significantly smoother than the North American one. Caution however is needed with the different ordinate scales as the sizes of the samples are significantly different.

In other words, from comparable total samples (respectively 1734 and 1728 entries), there are 536 West European associations (31%), but only 342 North American ones (barely 20%). This could result from two effects: either the North Americans are less of the associative vein than the West Europeans, or the North American associations have a shorter lifetime. In the latter case, the curve should be much steeper in the recent decades, which does not seem to be case, on the contrary. The weighted averaged foundation years of Table 1 confirm actually that the North American associations are older than the European ones.

As far as surges are concerned, the West European curve shows a few of them, for instance after WWII, around 1970 (Apollo 11 landing on the Moon) and at the mid-eighties. The North American curve has rather the surges in the first half of the thirties, after WWII, in the second half of the fifties (Sputnik I) and perhaps at the end of the seventies and of the eighties.

3.4 Planetariums

The cumulative distribution of the sample corresponding to the planetariums is illustrated in Fig. 13 from 1900 onwards.

Planetarium activities took off in practice with this century and knew a dramatic increase with the advent of the space exploration from the end of the fifties to the mid-seventies. The subsequent long-term trend of the curve is subsiding.

It is appropriate to mention here that - as recorded on our questionnaires - a significant number of planetarium facilities are nowadays used also for activities totally unrelated with astronomy.

3.5 Public observatories

The cumulative distribution of the sample corresponding to the public observatories is illustrated in Fig. 14 from 1900 onwards.

The oldest public observatory registered in the database is the York Observatory (UK/1831), followed by the Dumfries Observatory (UK/1836), Cincinnati Observatory (U.S.A.-OH/1845) and Sydney Observatory (Australia-NSW/1858).

Slight surges in the curve are noticeable after WWII, at the end of the fifties (Sputnik I) and of the sixties (Man on the Moon), as well as perhaps at the mid-seventies and mid-eighties.

3.6 Publishers

The cumulative distribution of the sample corresponding to the astronomy-related publishers is illustrated in Fig. 15 from 1900 onwards. Among the publishing companies founded earlier, one finds the Oxford University Press (1478), Cambridge University Press (1534), Johann Ambrosius Barth (1780), Friedrich Vieweg (1786), Taylor & Francis (1798), Masson Éditeur (1804), Wiley & Sons (1807), Springer-Verlag (1842), Hirzel Verlag (1853), and Cornell University Press (1869).

Astronomy-related publishing has been a steady activity. A few surges are however noticeable in the curve: in the first half of the twenties (after the plateau corresponding to WWI), in the second half of the forties (after WWII - notice however that the curve is not flat during the war), as well at the mid-sixties, mid-seventies and mid-eighties.

During WWII, Addison-Wesley was founded (1942), as well as Sky Publishing Corp. (1941), University of South Carolina Press (1944) and Vanderbilt University Press (1940), all in the US, the mainland of which was not touched by the war.

3.7 Software producers

The cumulative distribution of the sample corresponding to the astronomy-related commercial software producers is illustrated in Fig. 16. It calls for a very straightforward interpretation: the curve starts with the computer age (ENIAC's turn-on in 1946); a first surge is contemporaneous with Arpanet's commissioning (1969); after the mid-seventies, the electronic networks started spreading over the world; the eighties saw the popularization of the personal computers; and the first half of the nineties saw the advent of the WWW.