Crescent Venus

Here we see the crescent Moon rising over the serene Residencia at ESO’s Paranal Observatory. Next to the Moon Venus, the morning star, is also visible in the sky, and an array of ESO telescopes, now quiet after a night of observing, can be seen in the distance.

While too small to be seen on this image, Venus has different phases, similar to those of the Moon. We see Venus as a disc when Venus is creeping around the back of the Sun as seen from Earth — the Sun’s rays hit the face of Venus that is facing the Earth, and the image of this full face is reflected back to us. The crescent phase occurs when Venus emerges from behind the Sun into the part of its orbit that lies between the Earth and the Sun and progressively less of the surface is directly illuminated as seen from Earth. As Venus continues its march around the Sun, the crescent wanes, leaving just a sliver illuminated by sunlight. Until Venus reaches conjunction and disappears from our view before emerging as a thin, but waxing, crescent to start the cycle of phases once again.