Venus, the second closest planet to the Sun (at a distance of 108,200,000 km), is named after Venus, the Roman Goddess of love and beauty. Since Venus is the closest planet to the Earth, it can be seen a few hours before sunrise or a few hours after sunset. When it is at its brightest, it can be seen even during the daytime, making it the only heavenly body other than Moon which can be seen during the daytime. Venus is therefore sometimes referred to as the Morning or Evening star.
The astronomical symbol for Venus is a cross surmounted by a circle depicting feminity.
Astronomical Symbol
Astronomers refer to Venus as Earth's sister planet since both planets show similarity in their size, density and volume. However, with astronomical observations, scientists have proved that Venus is very different from Earth. Unlike Earth, Venus has no oceans and is surrounded by an atmosphere composed mainly of carbon dioxide with no water vapor. The surface atmospheric pressure of Venus is 92 times that of the Earth's at sea-level.
Venus globe Venus Inset Venus
Surface FeaturesOne of the distinguishing features of Venus is that it rotates from east to west, instead of west to east as a majority of the other planets do.
So far, four successful missions have been launched to Venus namely the Pioneer Venus mission by NASA (1978), Venera 15 & Venera 16 missions by the Soviet Union (1983-1984), and Magellan radar mapping mission by NASA (1990-1994).
Venus has a mean surface temperature of about 500 degrees C making it hotter than Mercury. This high temperature is a result of the greenhouse effect caused by the heavy atmosphere of carbon dioxide wherein sunlight enters the atmosphere to heat the surface but is trapped inside by the heavy atmosphere of carbon dioxide.
The surface of Venus comprises of vast plains covered by thick lava flows and mountains or bright highlands. Maxwell Montes in Ishtar Terra is the highest peak on Venus. The surface does not house any liquid water and therefore it cannot account for the bright highlands on the surface. However, a theory says that the presence of metals can be accounted for the brightness.
Other Features
Venus was once thought to possess a moon named Neith. It was first observed in the year 1672 by astronomer Giovanni Domenico Cassini. However, sightings of Neith have been confirmed as faint stars which when observed looked like a moon to Venus.
Earth View of Venus
Venus has a very dense atmosphere comprising mainly of carbon dioxide and nitrogen. The rotation speed of Venus is about 6.5 km/h which is very slow as compared to Earth’s rotation speed at 1670 km/h.
Owing to the dense atmosphere, the surface temperature of Venus reaches up till 500 degrees C making it the hottest planet in the solar system. On the contrary, the greenhouse effect is also responsible in keeping the planet much cooler.
The surface of Venus has been subject to lesser meteor attacks as compared to Mercury or Mars. The dense atmosphere breaks up the large meteors and burns the smaller meteorites.
Transit of VenusA transit of a planet occurs when it passes directly between the Sun and Earth. During a Venus transit, Venus can be seen from the Earth as a small black dot or disc moving across the Sun. Venus appears much smaller on the Sun’s surface as it is much further away from the Earth.
A transit of Venus is rare and occurs every 243 years in pairs of
transits 8 years apart. The most recent transit by Venus was observed on
June 8, 2004 and the next transit will be on June 6, 2012.
In 1631, Johannes Kepler became the first person to predict the occurrence of a transit of Venus. However, its first observation was made only in 1639 by Jeremiah Horrocks.