23. BACKSCATTERING OF LIGHT BY SNOW
221
The measurements were made outdoors, which allowed a long baseline
of 10 to 40 meters. The smallest possible phase angle was 0.3 degrees, which
is well within the opposition spike of bright planetary objects. The main
disadvantage was the maximum phase angle, which was only about 3
degrees when the baseline was 40 meters. However, the phase curves
measured using the 10-m baseline extended the range of phase angles to 10
degrees. The measurements were carried out in the winters of 1979-80 and
1980-81 during nighttime and in as dry weather conditions as possible.
221
The measurements were made outdoors, which allowed a long baseline
of 10 to 40 meters. The smallest possible phase angle was 0.3 degrees, which
is well within the opposition spike of bright planetary objects. The main
disadvantage was the maximum phase angle, which was only about 3
degrees when the baseline was 40 meters. However, the phase curves
measured using the 10-m baseline extended the range of phase angles to 10
degrees. The measurements were carried out in the winters of 1979-80 and
1980-81 during nighttime and in as dry weather conditions as possible.