THE PLANET VENUS AND ITS BEHAVIOR.

Going away from the Sun, the 4 solid and rocky planets that orbit around it are: Mercury, Venus, Earth, and Mars. 

Venus is the same size as Earth and is our closest planetary neighbor. The mean surface temperature of the planet is 870F while the Earth is 72F. Venus is hotter than Mercury even though it is twice as far from the Sun as Mercury. 

Venus's atmosphere is mostly carbon dioxide with thick yellow-white clouds of sulfuric acid; these clouds becomes highly reflective -reflecting about 70% of incoming sunlight back into space. They are largely responsible for the high heat on the surface of the planet because of their "greenhouse effect" on the incoming energy from the Sun. Venus is the third brightest luminary in our sky -only the Sun and the Moon are brighter. For long periods of time, Venus becomes bright enough to cast shadows on Earth. The atmospheric pressure on Venus's surface is 92 times that of the Earth. That is about the same pressure as being 1 km/1.6 mi under water, in which our bodies are instantly squashed and burned. 

Venus orbits the Sun in about 225 earth-days, while the Earth does it in about 365 days. Venus rotates in its axis slowly and in the opposite direction from all the other planets in our solar system except Uranus. The Sun rises in the West and sets in the East. It takes 243 earth-days to make one rotation, therefore "One Venus Day" is longer than "One Venus Year."

The periods of Venus as "Evening Star" and "Morning Star" each average about 263 days. In between, Venus disappears from our view on the Near side of the Sun for about 8 days, and from the the Far side of the Sun for about 50 days. The entire cycle is made in 584 days.

Venus is the third brightest luminary in our sky -only the Sun and the Moon are brighter. For long periods of time, Venus becomes bright enough to cast shadows on Earth. 

Venus has phases like the Moon: full, half, quarter, crescent, etc. The planet appears to us at its brightest when its phase is only a quarter or less. When Venus is its full phase, it is on the opposite side of the Sun, the farthest possible distance from Earth. As the orbits of Earth and Venus bring them closer together (on the same side of the Sun), Venus appears brighter even though we are seeing only a quarter of the planet.

A Venus passage occurs when we can see Venus passing directly in front of the Sun. It is similar to a Solar Eclipse, when the Moon passes in front of the Sun. This passage can only occur with the inner planets -Mercury and Venus- because they are the only 2 that can lie between the Earth and Sun during their orbits.

Venus passages usually come in pairs, with each passage spaced 8 years apart. We are in the midst of the first and second passages of this millennium. It is a rare once-in-a-lifetime event. The last Venus Passages (pair of) occurred in 1874 and 1882. The next pair will occur in 2117 and 2125.

The English word "Friday" is derived from the Anglo-Saxon "Frigedaeg," meaning "Venus Day." The name Venus comes from the Roman goddess of beauty and love.