REPORT ON LIGHT OBSERVED BY NEW PLYMOUTH, ON 1955 NOVEMBER 5
Calculated Data for Venus.
Mouth of Mokau River:
Lat. 38° 42' S
Long. 174° 39' E
Venus:
Declination 20°07' S
L.H.A. 101° 37' .5 W at 0800 G.M.T.
105° 22' .3 W at 0815 G.M.T.
Time Zone: 12 hours E of Greenwich
N.Z. Time p.m.
Altitude of Venus
True Bearing
08 00
3° 51' .8
247° 11' .7
08 15
1 11 .2
244 58 .6
The altitude is true, uncorrected for refraction or dip.
REMARKS:
1. From the above data, Venus would set for an observer at sea level, at 8.25 p.m. assuming a refraction of 34'. Abnormalities of refraction together with the height of eye could make this a few minutes later, agreeing very well in general with the observation.
2. The general direction given by the observer agrees so closely with the calculated bearing as to leave little doubt.
3. The diurnal motion would give the exact effects noted by the observer, viz., dropping to the horizon and moving to the south.
4. The colour and colour changes are in accordance with what is to be expected with a setting object. As an example there is the redness of the Sun when on the horizon. This is due to the absorption of shorter wavelengths of light by the horizon atmosphere.
5. The circling movement noted at the beginning of the second paragraph could be due to a not uncommon phenomenon of refraction effects causing stars to appear to move irregularly in the sky, together with the fact that the observer could not be fully assured of a steady line of sight without instruments.
CONCLUSION:
All the evidence points very definitely to an observation of the setting of the planet Venus.
Cont'd...