Valdemar Axel Firsoff was known principally as an amateur astronomer. He was born in ca. 1910 of Swedish descent, and died on 19 November 1981. He lived in Lochearnhead, Scotland, before moving to Somerset, England, where he settled in Glastonbury.
Axel Firsoff held an MA degree in languages and worked as a Swedish translator and in the United Kingdom Patent Office. He was a keen mountaineer and skier, as some of his earlier books reveal, and he was a ski instructor for the British Olympic Ski Team in the 1950s. He developed an interest in science, in particular geology and astronomy and this led him to publish numerous books on the moon and inner planets.
Many of his books also touched on extraterrestrial life and the nature of the mind. In Life, Mind and Galaxies, he speculated that "mind seems to be an entity of the same order as energy and matter", an idea well before its time. In other aspects of his work, such as the nature of the lunar craters, which he considered to be of volcanic rather than cosmological origin, he was later proved to be well wide of the mark.
Selected bibliography 
- Ski Track on the Battlefield - 1942
- The Tatra Mountains - 1942
- The Unity of Europe - 1947
- The Cairngorms on Foot and Ski - 1949
- Arran With Camera and Sketchbook - 1951
- Our Neighbor World - 1953
- In the Hills of Breadalbane: Illustrated from the author's photos and drawings - 1954
- Moon Atlas - 1961
- The Surface of the Moon - 1961
- Strange World of the Moon - 1962
- The Crust Of The Earth - 1962
- Life Beyond the Earth: a study in exobiology - 1963
- Facing the Universe - 1966
- Life, Mind and Galaxies - 1967
- The Interior Planets - 1968
- The Old Moon and the New - 1969
- The World of Mars - 1969
- Gemstones of the British Isles - 1971
- Life among the Stars - 1974
- Working with Gemstones - 1974
- The Rockhound's Handbook - 1975
- The Solar Planets - 1977
- At the Crossroads of Knowledge - 1977
- The New Face of Mars - 1982
- Patrick Moore (1982), Obituary, Quarterly Journal of the Royal Astronomical Society, Volume 23, pp. 629–630.
- Preface in Life, Mind and Galaxies (1967)
- Second-hand book web-sites including Amazon