Venus(the Earth’s lost twin) is the closest planet in the Solar System after Mercury from the sun and is the closest planetary neighbor to the planet Earth. It is the 2nd brightest astronomical object after the moon in the night sky from the Earth. It is visible from the naked eye and it can cast a shadow on rare occasions. It is also known as Earth’s twin or sister planet as it is similar in size and structure to the Earth. Like Mercury, Venus doesn’t have any moon, among all other planets it shares a distinction with Mercury.
To know more about Planet Mercury, read our in-depth article: “Mercury (The Smallest Planet)”
Venus lies in the habitable zone and also it lies in Earth’s orbit. Venus is named after the ancient Roman goddess of love & beauty, and who was known as the Aphrodite to the Ancient Greeks. Venus spins(rotates) slowly and in opposite(Anti-clockwise) direction with respect to all other planets. Its thick atmosphere traps heat from the sun, causing greenhouse effects. This phenomenon makes Venus the hottest planet in our solar system. Its surface temperature is hot enough to melt lead.
Contents in this article:
Physical Appearance of Venus
It is a terrestrial planet amongst the four planets of the solar system. It is similar in size and mass to the Earth and it is a rocky planet body, often called Earth’s sister or twin. It has a diameter of 12,103.6 km(7520.8 mi), which is only 638 km less than that of Earth. Its mass is 81.5% of the mass of Earth. The average distance of this planet from the sun is 0.7 AU and it takes about 6 minutes for sunlight to reach its surface. Its atmosphere is dense in carbon dioxide(96.5%) and the most remaining is nitrogen, which makes about 3.5%.
Orbit and Rotation
The rotation of Venus and its orbit is quite different from other planets. It is one of the two planets that rotate in an anti-clockwise(East to west) direction after Uranus. It completes one rotation in about 243 Earth days and revolves around the sun in about 225 Earth days. Thus, a day on here is longer than its whole year. It has the longest day, as compared to other planets. Its orbit around the sun is most circular as compared to the other planets with an eccentricity of less than 0.01, which is nearly a perfect circle, and orbits of other planets are more oval and elliptical in shape. It spins on its axis nearly upright, which is tilted axially about 3°C
Surface and its Atmosphere
It looks bright white from space because its atmosphere is covered with a cloud that reflects and scatters the light coming from any other source like the Sun. Its surface is rocky(like Earth) and has different shades. Moreover, the atmosphere would look orange in color if one stands on the Venusian surface as it filters the sunlight and its atmosphere is thick.
Like Earth, it has got mountains, about 10,000 volcanos, and valleys. But unlike earth, it doesn’t have water. Maxwell Montes is the highest mountain and its height is about 20,000 feet(8.8km) similar to the highest mountain on the Earth(Mount Everest). The surface temperature of Venus is 471° C(880° F). And it has a dusty landscape.
Venus is the brightest object in the night sky after the moon. It appears as a white bright dot with an apparent magnitude of 4.14 along with a standard deviation of 0.31, which is brighter than other planets in the solar system. The brightest phase of its is the crescent phase a month before and after inferior conjunction. It is bright enough to cast a shadow on the earth and it can be seen on a middy day.
After every 584 days, Venus overtakes the Earth as it orbits the Sun, though, it changes from the Evening star(visible after sunset) to the morning star(visible before sunrise).
Potential of Life on Venus or Habitability
Before mid of the 20th Century, the Surface condition was believed to be similar to the Earth, and it was widely believed that Venus could be suitable for life. But in 1870 Richard Proctor( British astronomer) said that life was impossible near the equator of Venus, but was possible at the poles.
But in the 1960s, a spacecraft sent did not last long on its surface due to extreme surface conditions. And space probes cleared the evidence and showed the extreme surface temperature(i.e constant temp of about 500 °C). The atmosphere contains a cloud of sulfuric acid and rainfall on its surface is sulfuric acid. The atmospheric pressure is about 100 times greater than the earth’s, which is 90 bar. In late 1967 astronomer, Carl Sagan and Harold Morowitz analyzed and published the issue of life on Venus in the journal Nature. Mariner 2 sent by NASA in 1962 became the first spacecraft to flyby successfully past Venus.
Since the early 2000’s the international Venus Scientific community has conducted several studies regarding priorities for future exploration of Venus. Very recently, on the 14th of September 2020, scientists revealed that Phosphine was discovered in its atmosphere about 55km above the surface. Scientists doubt that this could be a source of some anaerobic life forms and giving a lead to explore Venus furthermore. In 2017, ISRO had also announced its future missions to Venus.