Albedo used in astronomy are the (V-band) geometric albedo (measuring brightness when illumination comes from directly behind the observer) and the Bond albedo (measuring total proportion of electromagnetic energy reflected). Their values can differ significantly, which is a common source of confusion. In detailed studies, the directional reflectance properties of astronomical bodies are often expressed in terms of the five Hapke parameters which semi-empirically describe the variation of albedo with phase angle, including a characterization of the opposition effect of regolith surfaces. The correlation between astronomical (geometric) albedo, absolute magnitude and diameter is: formula_7, where formula_8 is the astronomical albedo, formula_9
Albedo 0.39 track, "Albedo 0.39" is an atmospheric track building on waxing and waning synthesizer chords and arpeggios, while a voice, reputedly the album's engineer Keith Spencer-Allen, narrates various physical properties of the Earth, such as its mass, length of the year in various measurements, and, finally, its albedo. Mike DeGagne of Allmusic described the tracks as "mesmerizing trips of assorted rhythms that include elements of jazz and mild rock", that along with "Albedo 0.39", "the two parts of "Nucleogenesis" are among the strongest cuts that keep his cosmic theme from deviating, while the livelier "Pulstar" involves some impressive instrumental range and