I have been interested in stars and especially in star maps for almost all my life. In 1977, at the age of 34, I started working on my first star atlas. Five large maps, showing the whole sky, with stars down to magnitude 6.5. It was published in the book Encyclopedia of Astronomy (edited by Colin Ronan), and later as a separate set of star maps by the British Astronomical Association (B.A.A.). The title: B.A.A. Star Charts 1950.0.
After that, still as a hobby, I started working on Sky Atlas 2000.0, with stars down to magnitude 8.0. After it's publication in 1981 (Sky Publishing Corporation / Cambridge University Press), publishers started asking me to do star maps and star atlases for books and magazines. This resulted in quitting my job as a graphic artist and designer, and starting as a full-time star-map-maker (uranographer) in 1983. Since then I have worked on numerous star maps for atlases, books and magazines.
Over the years a lot of things have changed in the way star maps are created, and in fact in the whole area of graphic arts. My old drawing table is now replaced by an Apple computer. I use several graphic programs, of which Adobe Illustrator (a vector drawing program) is the most important.
On November, 7, 1987 I received the 'Dr. J. van der Bilt-prize'; a reward from the "Nederlandse Vereniging voor Weer en Sterrenkunde", a Dutch organisation for weather and astronomy amateurs.
On September 1, 1993, the Internationale Astronomical Union
named a minor planet (asteroid) after me:
(4648) Tirion = 1931 UE
Discovered 1931 Oct. 18 by K. Reinmuth at Heidelberg.