Historical story

The Discoverers of Heaven by David Baneke on Dutch Astronomy

The Netherlands has been at the forefront of international astronomy for at least a hundred years. David Baneke delved into the world of Dutch astronomy and discovered why we are so good at it. The historian of science delivers with The Discoverers of Heaven a very accurate description of all important events in the Netherlands.

“The Netherlands is the worst conceivable place for astronomy.” David Baneke gets straight to the point at the beginning of his book. And yet the poor observing conditions – including clouds, high humidity and light pollution – have not prevented the Dutch from becoming one of the top countries in international astronomy.

The Explorers of Heaven tells the history of astronomy in a chronological way and starts in the 17 e century. Leiden and Utrecht were given observatories, which professional scientists did not use. See you in the 18 e century, astronomy was mainly practiced by amateurs, interested parties and by seafarers who navigated on the stars.

This changed in the 19 e century, when heads of state began to use astronomical discoveries to display their knowledge and power. The English and French astronomers were superior. The Dutch king Willem I did not want to be left behind and ordered two large reflecting telescopes. Unfortunately, the quality of the devices was not high enough to start with.

Luminescent signs

Baneke writes that the more organized national astronomy during the 19 e century got off to a flying start. For example, the Amsterdam society for art and science Felix Meritus wanted to establish itself from the end of the 18 e century were eager to plunge into the stars, but they had chronic problems finding a suitable observer. Gradually the 19 e century, universities became interested in astronomy.

During the transition to the 20 e century, astronomy prospered. Techniques such as photography and spectroscopy were introduced, institutes grew and new ones were added, for example in Groningen. Astronomers were not put in the way. It was the time when the Groningen professor Jacobus Cornelius Kapteyn was given a special key by the municipality to switch off illuminated signs if this affected his measurements.

Start 20 e century, great discoveries followed each other faster and faster. For example, it was discovered that the universe was expanding and that it had to be much larger than astronomers had always suspected. During this period, Dutch astronomy flourished, probably due to a combination of factors. In addition to a batch of very talented astronomers, the expansion of universities, good technical training and the right international contacts also played a major role. Incidentally, Dutch astronomy was small:eighteen people were active throughout the country during the interwar period!

After the Second World War, radio astronomy emerged, partly due to the invention of radar. Jan Hendrik Oort, a very influential astronomer from Leiden, proposed building the largest radio telescope in the world. The government agreed and the Dwingeloo radio telescope was built with a satellite dish with a diameter of twenty-five meters. With radio astronomy, astronomers were given a new set of eyes, which made completely new research possible into extremely distant galaxies, for example. Almost fifteen years later, with the Westerbork Synthesis Radio Telescope, the Netherlands once again received the world's largest radio telescope.

Dutch satellites

Baneke also writes extensively about the cold war and the spacerace which is favorable for astronomy. In addition to the optical and radio spectrum, the ultraviolet, infrared, and X-ray spectrums have also proved useful to astronomers. These wavelengths are particularly easy to study from space (in the absence of atmospheric disturbance). At the time, the Netherlands had no small ambitions and developed and launched two satellites together with the United States. Furthermore, Baneke describes in detail the emergence of the European Space Agency (ESA) and the European Southern Observatory (ESO), which saw the light around this time.

The book creeps into the now. The large LOFAR radio telescope, whose heart is in the Netherlands, is discussed. And of course the closure of the astronomy department of Utrecht University in 2011. Baneke rightly writes that this is the biggest crisis in Dutch astronomy in a hundred years. With the help of the umbrella research school NOVA, the blows were absorbed as best as possible. Today, about 650 people work in Dutch astronomy. It involves 75 million euros per year.

Declaration of success

At the end of the book Baneke tries to explain the prominent role of the Netherlands in astronomy. He offers many (possible) explanations for this. Astronomers, such as Kapteyn, Minnaert and Oort, successfully seized every opportunity presented to them. They also made good use of Dutch politicians, who wanted to join the international top where possible. When major projects threatened to fail, the astronomers often came up with an even more ambitious one.

Although the Dutch astronomical community was small, it was also decisive and managed to attract a lot of outside talent through top facilities such as the Dwingeloo, Westerbork and LOFAR telescope. “Since the 1980s, the Netherlands has regarded itself as one of the top three countries in astronomy,” says Baneke.

Extremely careful

In The Explorers of Heaven Baneke has worked extremely carefully. He spoke with countless astronomers and delved deep into the archives of observatories. He lists the sources neatly in a long bibliography at the end of the book. Together with the introduction, in which Baneke explains what he researched and why he made certain choices, this gives the book the solidity of a dissertation.

His writing style is clear but also quite factual. From time to time the reader is bombarded with tricky terms like Humboldtian science or a Six-inch Merz refractor which are not explained, but the book is generally quite easy to follow.

Almost too extensive

The strong point of the book is actually also its biggest pitfall, namely its extensiveness. Almost every astronomer who has made a difference in Dutch astronomy in recent centuries is discussed, almost every astronomical organization that has been founded mentions Baneke and he does not skip a single issue. The more than three hundred page book is therefore actually overcrowded and an overload is lurking.

Furthermore, astronomy itself is actually very sparsely offered. It is true that there is no development that has not been described – the emergence of photography, spectroscope, increasingly larger telescopes – but science is usually condemned in this book to a subordinate clause that briefly clarifies it.

Of course that is not the approach of this book, it is not called The Discoverers of Heaven. for nothing. But a reader who, in addition to all the personal and organizational adventures, also wants to learn something from science may be disappointed. One thing is clear:if you are really interested in the history of successful Dutch astronomy, this book should be on your shelf.