Every 584 days Venus appears in the west as an evening star, first appearing about 20 minutes after sunset, near the horizon._-_figure_147.jpg)
VENUS.
Showing crescent phase. Photographed with the 40-inch refractor at the Yerkes Observatory. After being visible but a short time, it disappears from view not far from the point where the sun went down.
Every succeeding day this star appears at a higher elevation and glows brighter and brighter; this continues for several months until it appears like a great lamp, outshining every other object in the heavens, except the moon. It then begins to appear at a lower elevation each evening and to set a little earlier, until in the course of two or three weeks it disappears in the early twilight. About two weeks after her departure from the evening sky, Venus appears in the east shining brightly in the cool, gray hours just before Aurora opens the gates for the Sun-god.
Day by day, the Morning Star increases in brilliance just as did the Evening Star until it appears at the highest point above the horizon; then its light gradually declines as each day its stay becomes shorter and shorter, until finally it pales in the morning light and is immersed in the rays of the sun.
Venus passes through its period of greatest brilliance every eighth year. This last occurred in 1921 and will next occur in 1929. At such a time the planet is so bright that it may be seen in daylight, if one knows where to look for it.
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The discovery through a telescope that Venus had phases firmly established the theories of Copernicus. When this Polish astronomer, in 1543, announced the astounding theory that the sun was the center of our solar system, he said that if the planets between the earth and the sun could be
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