Venus, Nine Planets in Universe
Venus is the second planet from the Sun and the sixth-largest. Together with Mercury, they are the only planets without a satellite, even though Mercury is closer to the sun, Venus is the hottest planet.
It isn’t possible to pinpoint the exact discovery date of Venus. Due to its brightness, it can be easily seen with the naked eye, meaning that any ancient civilization could be credited with the first observation. Copernicus, and later Galileo Galilei, are however credited with Venus’s classification as a planet while Mikhail Lomonosov has been credited with initially discovering the planet’s gaseous atmosphere in 1761. This claim was later verified in 1790 by astronomer Johann Schroter.
Though it has been visually observable for as long as mankind can remember, the naming of Venus is again a bit of a mystery. Venus received its most popular moniker via a selection of Roman gods and goddesses. Venus was named after the Roman goddess of love and beauty, a counterpart to Greek’s Aphrodite. It wasn’t always known as such. Ancient Babylonians who recognized Venus, for example, named it the Star of Ishtar, their own goddess of fertility, love, and war.
The symbol for womanhood has even been adopted as the symbol of this planet of love and strong women, being the first and only one with a feminine name. Prior to being officially dubbed Venus, Greeks and Romans had unknowingly turned Venus into two different stars.
To the Greeks, Venus was both Phosphorus and Hesperus and to the Romans, it was recognized as Lucifer and Vesper. Both nations didn’t know that the alleged two stars they were referencing were actually one body until later when further observations were conducted and its orbit was understood.
It is theorized that Venus was formed about 4.5 billion years ago when gravity pulled swirling gas and dust together to form the second planet and it later settled into its current layout.
Distance, Size, and Mass
Venus is the second closest planet to the Sun, at a distance of 108.2 million km/ 67.24 mi or 0.7 AU receiving the sun’s light in 6 minutes. Venus has a radius of 6.051 km or 3.760 miles and a diameter of 12.104 km or 7.521 mi, slightly smaller than Earth.
It has a mass of 4.87 × 1024 kg, or 85% that of Earth. The mentioned similarities also give way to similar densities, Venus having a density of 5.24 grams per cubic centimeter, while Earth has 5.52. It also has as much volume as Earth – 928.45 billion cubic km compared to Earth’s 1083.21 billion.
Its closest approach to Earth happens once every 584 days, when the planets catch up to one another. On average it can get as close as 25 million miles or 40 million kilometers to Earth the equivalent of about 0.28 AU.
One of the reasons that ancient civilizations unknowingly turned Venus into two separate stars – The Mourning Star and The Evening Star – was that they didn’t understood its orbit. Venus goes from being visible only after sunset to only being visible prior to sunrise when its orbit around the sun surpasses Earth’s orbit.
Venus orbits the Sun at an average distance of about 0.72 AU and completes an orbit every 224.7 days. Though most planetary orbits are elliptical, Venus’s orbit is the closest to circular with an eccentricity of less than 0.01. When Venus lies between Earth and the Sun in inferior conjunction, it makes the closest approach to Earth of any planet at a distance of 41 million km or 25 million miles. Venus spends most of its time away from Earth. This paradoxically makes Mercury the closest planet to Earth, a plurality of the time.
The orbit is a bit inclined relative to Earth’s orbit. When Venus passes between Earth and the Sun, it usually doesn’t cross the face of the Sun.
Transits of Venus occur when the planet’s inferior conjunction coincides with its presence in the plane of Earth’s orbit.
Transits of Venus occur in cycles of 243 years with the current pattern of transits being pairs of transits separated by eight years, at intervals of about 105.5 years or 121.5.
To know about Mercury https://www.knowledgebeach.com/mercury-nine-planets-in-universe/