Venus is the second planet closest to the Sun of our Solar System and the sixth in size (from the largest to the smallest), baptized in honor of the Roman Goddess of love and seduction, the same as the Greeks called Aphrodite.
It is a rocky and terrestrial planet, of similar size, mass and composition to our planet, which is why it has often been considered as its “brother” planet. However, it is completely different in matters of temperature, atmosphere and pressure.
This planet has been observed by humanity since ancient times, since it is one of the three stars visible to the naked eye during the day (next to the Moon and the Sun), being the third in brilliance (after the Moon). Given its appearance after sunset or sunrise, it has been baptized as the “morning star” and is part of many poetic compositions, traditional astrological theories and ancestral calendars.
Characteristics Of Venus
The orbit of Venus is located between Mercury and Earth, about 108.2 million kilometers from the Sun and only about 40 million kilometers from Earth, being the planet closest to ours that exists.
2. Dimensions and satellites
Venus has a diameter of 12103.6 kilometers and a volume of 9.28 x 1011 cubic kilometers (equivalent to 0.86 times that of Earth), in addition to a mass slightly lower than that of our planet (0.815 times).
It is a solitary planet, without satellites of any nature.
3. Orbital data
The orbit of Venus is the roundest of all of the Solar System (eccentricity of less than 1%) and lasts about 584 days. This displacement around the sun (translation) occurs at an average speed of 35.02 kilometers per second.
The planet also presents a slow rotating movement, which takes 243,01 Earth days to complete, and which occurs in the opposite direction to the rest of the planets (except Uranus).
This means that a Venusian day-night cycle would take about 116.75 Earth days, and a Venusian year only 1.92 of these cycles.
The pressure and temperature of Venus are extremely high, due to the composition of its atmosphere, mostly greenhouse gases. This pressure is 90 times greater than that of the Earth and its average temperature is 463.85 ° C (warmer than Mercury, despite being twice the distance from the Sun).
The Venusian atmosphere is composed mainly of carbon dioxide (96%) together with gases such as nitrogen (3%), sulfur dioxide (0.015%), water vapor (0.002%), carbon monoxide (0.0017%), argon (0.007%), helium (0.0012%) and neon (0.0007%). This dense layer of clouds almost completely prevents the arrival of solar radiation to the planet’s surface, so without it, its temperature would be similar to terrestrial.
Almost all (90%) of the surface of Venus consists of a basalt (igneous rock) with very few meteorite impacts (and therefore few craters), whose oldest formations do not seem to predate 800 million years (recent, in planetary time).
The planet has two large plateaus as continents, high on a broad plain: Ishtar Terra (north) and Aphrodite Terra (south). The first is equivalent to the size of Australia, the second to the size of South America.
It is assumed that the heart of the planet is similar to that of Earth (molten iron), with a rocky mantle around, interrupted by frequent volcanoes that line the surface with fresh lava constantly.
6. Magnetic field
Unlike Earth, whose rotation and iron core provide their own magnetic field that rejects solar radiation emissions, Venus receives them completely, because it lacks this magnetic shield.
This, according to the students of the planet, could have caused the decomposition of the existing water in hydrogen and oxygen: the first would escape to space due to its low molecular mass, while the second would combine in the atmospheric carbon dioxide. It is one of the explanations for which there is no life as we know it being a planet in principle similar to ours.
It is known as “transits of Venus” to the rare occasions in which the planet interposes between the Sun and the Earth, which allows to study certain characteristics of its composition. During his transit of 1761, for example, Mikhail Lomonsov found the first evidence that Venus has an atmosphere. This occurs only in June or December, in pairs separated by eight years (for example, in 2004 and 2012), and separated from the next pair in almost a century.
From the Earth, the phases of Venus can be observed, just like those of the Moon. Galileo Galilei was the first to notice them in 1610, noting the changes in their perceivable size and correctly interpreting them as the star was further away from us.
Venus shines brightest when 25% of its surface is illuminated by the Sun, which occurs 37 days before its conjunction with the Earth in the evening sky and 37 days after it in the morning sky.
9. Ashen lights
It is called this way to an unexplained phenomenon that takes place in the nocturnal half of Venus, and that consists of a yellowish or whitish halo emitted by the planet. It was first observed in 1643 by telescopes, and numerous explanations have been attributed to it, from visual illusions to electrical storms.
In astronomical notation, Venus is represented by the same symbol with which the female sex is traditionally designated, a circle with a small cross underneath.