Dutch celestial cartographer Wil Tirion, who created two landmark star atlases used worldwide by amateur astronomers, died July 5. He was 81 years old.
Tirion’s most popular work, Sky Atlas 2000.0, first published in 1981 by Sky Publishing Corporation and Cambridge University Press, contained 26 pages of maps that displayed stars as faint as magnitude 6.5. It came in several versions, including one with laminated pages that was a favorite of observers who lived in humid climates.
The second edition, which appeared in 1998, added 43,000 stars down to magnitude 8.5, seven “close-up” charts of crowded areas, and came in three options: The Deluxe Version had laminated pages and black stars on a white background, the Field Version had white stars on a black background, and the Desk Version had black stars on a white background.
Once the first edition of Sky Atlas 2000.0 appeared, Tirion found himself besieged with requests to create charts for other publications. So, in 1983, he began to do that full time.
His second atlas, co-authored with Barry Rappaport and George Lovi, was Uranometria 2000.0 Volume 1, The Northern Hemisphere to –6°, published in 1987 by Willmann-Bell. Tirion created the star charts for this 300-page book. It displayed all stars brighter than magnitude 9.5 plus some 10,000 deep-sky objects. The follow-up volume, Uranometria 2000.0 Volume 2, The Southern Hemisphere to +6°, which charted stars below the celestial equator, appeared the following year.
In 2001, Willmann-Bell published a new version of Volume 2. This 338-page work contained 280,000 stars and more than 30,000 deep-sky objects.
Tirion also contributed star charts to Bright Star Atlas 2000.0 (with Brian Skiff), Collins Night Sky (with Storm Dunlop), Men, Monsters, and the Modern Universe (with George Lovi), and Cambridge Star Atlas 2000.0.
In 1993, the International Astronomical Union honored Tirion by designating minor planet 1931 UE as (4648) Tirion. He is survived by his wife, Cokkie, and two children: Martin and Naära.
