Hannu Karttunen is a Finnish astronomer and science writer. He is an associate professor at Turku University and works at Tuorla Observatory. Besides astronomical articles Dr. Karttunen has published astronomy textbooks and teaching material as well as articles for anthologies and encyclopedias. Karttunen has also produced a radio lecture series on astronomy. Hannu Karttunen received the 1998 Tieto-Finlandia Award for his book Oldest science: Astronomy Stone Age to the mission to the moon, and, in2007, the Finnish News Writers Association Tietopöllö Award for his writings and books for children and young people.

Heikki Oja is a Finnish astronomer and associate professor at the University of Helsinki, as well as the former director of the Almanac Office. Dr. Oja has written dozens of non-technical non-fiction books and appeared frequently on the radio to talk about astronomy and space research. He has received several awards for his outreach activities.