Femke (book)

(bezoek deze website voor Nederlandstalige informatie)


In November 2018, Diego Cohen and I published a Children's book in Dutch about black holes. We are currently working towards an Icelandic, English and Spanish version. But please don't hesitate to contact me if you have suggestions for some other language. The book can be ordered in the Netherlands and Belgium via e.g. bol.com and in the Germany, France and the UK via Amazon. Click here for more info.


‘Femke and the black hole’ (link) is a richly illustrated book, meant to be read to children (4-6 year). The goal of this book is to introduce children to the seemingly difficult and abstract concept of black holes. Moreover, this book is also informative and amusing for people of other ages.


Everyone has heard of black holes, but what are they precisely? Physicists Diego Cohen and Watse Sybesma believe it’s about time that ‘black hole’ becomes a regular concept along the lines of ‘star’ and ‘planet’. Following the wisdom of ‘learned when young is done when old’, they focus their message towards young children.


The story, told in a rhyming manner, develops itself in the following way:

Femke’s adventure starts at night, when all of a sudden, her sock disappears through her bedroom window. During Femke’s search for her sock, she meets several celestial bodies. Finally, she stands eye to eye with a black hole, who turns out to be the one who stole here sock. Will she get her sock back?

Femke’s adventure is meant to be read to children. The story goes hand in hand with attractive drawings. In the back of the book one finds ‘Aftercare for the curious’ (‘Nazorg voor nieuwsgierigen’), in which it is clearly explained what black holes are, what happened to Femke’s sock and how she got it back (but with a twist). This part of the book is written in a more informative manner.

Unique features

This is the first book about black holes, written especially for children from 4 to 6 years old. It is therefore an essential addition to the currently existing children’s books. Also, the authors have ideas for follow ups to make the book into a series of books on accessible science topics. Finally, by choosing a female lead character, the book aims to contribute positively to female role models in STEM fields.