[Physics Class Notes] on Venus Planet Pdf for Exam

The solar system is formed by the Sun and the celestial bodies that revolve around it. It consists of a great number of bodies, such as planets, comets, asteroids, and meteors. The gravitational attraction between the Sun and these objects keeps them moving around. 

As you know, the Earth also revolves around the Sun. It’s a member of the solar system. It’s the planet. There are seven other planets around the Sun. The eight planets in their ranging order from the Sun are – Mercury, Venus, Moon, Mars, Jupiter, Saturn, Uranus, and Neptune.

Venus, the second planet in the Sun, and the sixth in the solar system in size and mass. No planet is closer to Earth than Venus; the closest to Earth is the largest body other than the Moon. Since the orbit of Venus is closer to the Sun than to Earth, the planet is still nearly in the same position in the sky as the Sun and can only be seen in the hours before sunrise or sunset. It’s the most bright planet in the sky when it’s clear. Venus is designated by the symbol ♀. 

 

Characteristics of Venus

Venus was one of the five planets identified in ancient times, along with Mercury, Mars, Jupiter, and Saturn, and its movements were observed and analyzed for centuries prior to the invention of sophisticated astronomical instruments. Its appearances were recorded by the Babylonians, who compared it to the goddess Ishtar, around 3000 BC, and it is also prominently listed in the astronomical records of other ancient civilizations, including those of China, Central America, Egypt, and Greece. Like the planet Mercury, Venus was known in ancient Greece by two separate names — Phosphorus (see Lucifer) when it appeared as a morning star and Hesperus when it appeared like a night star. The modern name derives from the Roman goddess of love and beauty (the Greek equivalent was Aphrodite), possibly because of the luminous jewel-like appearance of the earth.

 

The Atmosphere 

Venus has the most massive atmosphere on Earth’s planets, including Mercury, Earth, and Mars. Its gaseous envelope consists of more than 96 percent carbon dioxide and 3.5 percent molecular nitrogen. Trace amounts of other gasses are present, including carbon monoxide, sulfur dioxide, water vapor, argon, and helium. The atmospheric pressure at the surface of the planet varies with the surface elevation; at the elevation of the planet’s mean radius, it is about 95 bar or 95 times the atmospheric pressure at the surface of the Earth. This is the same pressure found at a depth of about 1 km (0.6 miles) in the oceans of the Earth.

 

Surface Composition 

A number of Soviet landers brought instruments to analyze the chemical composition of the surface materials of Venus. Since only the relative proportions of a few elements have been determined, there is no conclusive knowledge of the rock types or minerals present. Two methods have been used to measure the concentration of different elements. The concentrations of naturally radioactive isotopes of the elements uranium, potassium and thorium were measured by gamma-ray spectrometers carried out on Veneras 8, 9, and 10 and the landers of the Soviet Vega 1 and 2 missions. The X-ray fluorescence instruments carried on Veneras 13 and 14 and Vega 2 measured the concentrations of a variety of major elements.

 

Did You Know? 

 

Interesting facts about Venus

• Even though Venus is not the closest planet to the Sun, it is still the hottest. It has a thick atmosphere full of greenhouse gas carbon dioxide and a cloud of sulfuric acid. The atmosphere traps heat and keeps Venus warm. It’s so hot on Venus that metals like lead would be puddles of melted liquid. 

• Venus looks like a world that’s very healthy. It’s got mountains and volcanoes. Venus is very similar in scale to Earth. Earth is just a bit bigger

• Venus is unusual because it rotates in the opposite direction of Earth and most other planets. And the rotation is very slow.

 

Summary

• The solar system consists of eight planets and hosts of asteroids, comets, and meteors. 

• A body that rotates around another body is called a satellite. 

• The Moon is the Earth’s natural satellite. Some planets have natural satellites, too. 

• Venus is one of the brightest planets in the night sky. 

• Jupiter is the largest planet in the solar system.