Phase angle (astronomy) less than 90° represent backscattering; values greater than 90° represent forward scattering. For some objects, such as the Moon (see lunar phases), Venus and Mercury the phase angle (as seen from the Earth) covers the full 0–180° range. The superior planets cover shorter ranges. For example, for Mars the maximum phase angle is about 45°. The brightness of an object is a function of the phase angle, which is generally smooth, except for the so-called opposition spike near 0°, which does not affect gas giants or bodies with pronounced atmospheres, and when the object becomes fainter as the angle approaches
P-90 rather than subtract the signal between the coils; thus, the impedance can be lower, avoiding overwinding to obtain sufficient output. There is less signal cancellation. Sonically these sit somewhere between a true P-90 and a stacked pickup. They don't chime but they aren't nasal or lifeless either. They are ideal candidates for overdriven sounds where loss of sparkle is less important than avoiding hum amplification. These type of pickups have the same appearance of P-90s. The new generation Zero-Hum P-90 Hx by Kinman strives to have a P-90 sound and appearance, but is far more complex, with 202 individual parts.