One Century of Planetary Images

The database of planetary images (BDIP) comes from the digitization of photographs collected and preserved by the Center for Photographic Documentation of the planets held by the IAU at the Meudon Observatory in 1961 under the the curation of J.H. Focas (IAUC, 12th General Assembly, Report 1964). A similar center was established at the Lowell Observatory in Arizona, under the responsibility of W.A. Baum. The photographs were duplicated between the two centers.

Approximately 8400 photographs of Mars, Venus, Mercury, Jupiter and Saturn, acquired between 1890 and 1977, are kept at LESIA. They remain available for research on justified request. The digitization of these planetary photographs was performed by scanning between 1998 and 2000 by the staff of the Documentation Center (R. Boyer, E. Neyvoz et al), in the framework of a project proposed to the Scientific Council of the Paris Observatory by P. Drossart. Care was taken to preserve the best possible definition and photometric linearity of photographs during the scanning procedure. Storage was done using different image formats (JPEG, GIF and TIFF ie, lossy, lossless and uncompressed). Improved techniques for mass storage and network distribution today allow us to provide access to the highest definition images, thereby facilitating research on the evolution of planets, at asecular time scale.

Scientific interest

The scientific interest of the photographic database mainly concerns planetary atmospheric evolution of Mars, Jupiter, Saturn and Venus. The evolution of the Martian storms, or the polar caps on Mars, the survey of storms observed on Saturn, or features like the Great Red Spot of Jupiter or oval white spots are among the subjects which triggered on photographs. Such studies can be refined today thanks to digital pictures (Sanchez-Lavega and Battaner, A and A Suppl. Ser., 64, 287, 1986). Some images of Mercury are also available.