  Sundial is the ancient or classic timekeeper device, especially prior to the
invention of mechanical clock. In the classical Islamic civilization, the daily
movement of the Sun becomes main indicator of praying time, which can be
deduced using sundial. This kind of device probably permeated to Indonesia
during the Islamic acculturation. Since then, the development of astronomical
knowledge, technology, art and architectural in classical Indonesia are
partially reflected into sundial. These historical attractions of sundial
demand comprehensive documentation and investigation of Indonesian sundial
which are rarely found in the current literatures. The required spatial and
temporal information regarding Indonesian sundial can be collected by general
public through citizen science scheme. This concept may answer scientific
curiosity of a research and also educate the people, expose them with science.
In this article, general scheme of citizen science are discussed, its
application for sundial study in Indonesia is proposed as Suryakala-Nusantara
program.
