# Hapke parameters

The

**Hapke parameters**are a set of parameters for a quasi-experimental model that are commonly used to describe the

directional reflectance properties of the airlessregolith surfaces of bodies in thesolar system . They were developed by astronomerBruce Hapke at theUniversity of Pittsburgh .#$ar\{omega\}\_0$ — Single scattering

albedo . This is the ratio of scattering efficiency to total light extinction (which includes also absorption), for small-particle scattering of light. That is, $K\_s/(K\_s+K\_a)$, where $K\_s$ is thescattering coefficient , and $K\_a$ is theabsorption coefficient [*http://scienceworld.wolfram.com/physics/SingleScatteringAlbedo.html Single Scattering Albedo*] , scienceworld.wolfram.com.]

#$h$ — The width of the opposition surge.

#$B\_0$ or $S\_0$ — The strength of the opposition surge.

#$P\_0$ or "g" — The particle phase function parameter, also called the asymmetry factor.

#$heta$ — The effective surface tilt, also called the macroscopic roughness angle.The Hapke parameters can be used to derive other albedo and scattering properties such as the

geometric albedo , thephase integral , and theBond albedo .**ee also***

albedo

*Geometric albedo

*Bidirectional reflectance distribution function **References**

*Wikimedia Foundation.
2010.*

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