Equal-Area Maps for Irregular Objects

Introduction

    The mapping technique illustrated here was developed to analyse the surface distribution of craters on the asteroid 433 Eros. It uses an azimuthal projection with oblique aspect. A detailed description of the technique can be found in:
Berthoud, M. G. 2005. An equal-area map projection for irregular objects, Icarus 175, pp 382-389 (2005) (
PDF)

Maps

Eros
    The following map shows the global basemap for Eros on two equal-area maps. The basemap is described in Bussey et al. (2002). The shape of Eros used here is described in Thomas et al. (2002). Also shown are the outlines of the three large depressions Himeros, Psyche and Shoemaker Crater from Thomas et al. (2002). Thanks to Peter Thomas for the shape model and Mark Robinson for the global basemap.

PDF of the same image.

    The following maps show a black 30° and a gray 10° graticule of the mapped body. The squares on the left are for scale and cover the corresponding area on the map. For Ida and Phobos a 2° shape model was used and a 5° one for Deimos. The shapes of Phobos and Deimos are described in Thomas (1993). The 2° shape of Ida is described in Thomas et al. (1996). Thanks to Peter Thomas for providing the shape models.


Phobos
Hemisphere centered at 270W 0N

Hemisphere centered at 90W 0N


Deimos
Hemisphere centered at 270W 0N

Hemisphere centered at 90W 0N


Ida
Northern Hemisphere

Southern Hemisphere

    Although area is well conserved on the map the highly irregular shape of the asteroid causes large distortions.

Links on Related Subjects

References

Contact

For questions and suggestions please contact me at
berthoud@astro.cornell.edu