The term opposition spike refers to the surge in a planetary body's apparent magnitude as it reaches astronomical opposition with respect to an observer.

Its causes are complex and only partially understood, but are thought to be involve the sudden elimination of shadowing effects at zero solar phase angle.

See also

• Bidirectional reflectance function

References

• Drake, J.S. 2004, A Photometric Study of Phocaea Group Asteroid 1584 Fuji, Senior Honors Thesis, Department of Physics and Astronomy, Dickinson College, Carlisle, PA

Observational astronomy