Throughout different religions, a place for abomination and punishment for those who sin has been mentioned, and called ‘Hell’. Hell, Hellish, and similarly derived words became a synonym for torment and pain. The major similarity in all these versions of hell is that it is mostly compared to a place that is always burning, with scorching temperatures that can melt anything, and it is located ‘below’ the Earth we live in. But astronomers would beg to differ. They say the hell in our solar system, is above us, in the skies. On 4th December, 1639 English astronomer Jeremiah Horrocks was the first person to observe the transit of Venus (from his home). What makes him stand out in comparision to his predecesors, who also observed the planet, is that while they thought it was actually a ‘star’, he was the first to record its movement and transit as a planet in our solar system, named Venus. With temperatures as high as 400 to 740 Kelvin (high enough to melt lead), atmosphere of sulphuric acid, and collapsing pressures, Venus is indeed the Hell of our planetary system. Let’s know more about the hottest planet in solar system(amazing pics too!).
The irony is that Venus is named after the Roman god of Love and Peace. This is perhaps because how it appears to us from here, a ‘star’, shining brightly in the night sky, which honestly looks kind of beautiful. It is second brightest object in the night sky after our Moon, and with clear skies, it can also be seen during the day as a dim dot. Because of its distance from us and the light its atmosphere reflects at us, it appears to be a star. It is the first ‘star’ to appear in the evening and the last one to fade away in the morning and is thus sometimes referred to as the “Evening star” or the “Morning star” respectively. Earlier it was thought that the evening and morning views of the planet as two different stars, and called them Eosphorus and Hesperus respectively. It was Babylonians who first realized it was the same object in 1561 BCE. In other cultures, Venus has been named Ishtar (Babylonians), Aphrodite(Greek), Lucifer and Vesper(Roman; for morning and evening aspects). In 1032, Persian astronomer Avicenna was the first to deduce that Venus was closer to us than the sun, and Galileo was the first to observe that Venus also showed phases(similar to the moon), meaning that it revolved around the sun, thus helping him fight the Ptolemic model(Earth-centered) and hence support the Copernican view(with the sun at the centre). Later, observing that the crescent phase of the planet extended beyond 180◦, German astronomer Johann Schröter deduced that it had a dense atmosphere which reflected sunlight. And hence began the journey to understand our neighbour.
It was in 2012, when Venus grabbed my interest for the first time in particular. It was passing directly between the Sun and Earth, and could be seen as a black spot with Sun in the background. This is a very rare phenomena, and will next take place in the year, 2117. I remember going to a scientist’s house, and observing the whole event using special glasses through his telescopes. One of my most vivid experiences. Later I read about in Carl Sagan’s Cosmos and was taken back by all the ‘different’ aspects of it. Since then I have spent countless nights watching it fade into the morning while thinking of the chaos it holds within.
With almost 70% the size and 80% the mass of our Earth, Venus is often called our ‘Sister planet’ (which honestly makes it an evil sister). Because of its resemblance in size and chemical composition to Earth, it was first thought to possibly support life. It is the closest planet to Earth, and is ‘just’ 41 million kilometers away during its conjunction. One of its ‘different’ behaviour is that it is the only planet in our system to rotate anti-clockwise( retrograde Rotation), which is thought to be because of a past collision with an asteroid or something, which was strong enough to change its direction of rotation. Add to this the weird part that one venusian day(243 Earth Days) is longer than a venusian year(225 Earth days), almost as long as one Monday(not literally!).
There have been many missions, both failed and successful, aimed at understanding our nightmare planet. Venera 1(also called Sputnik 8; by the Soviets) was the first lander launched, but 7 minutes into the planet’s atmosphere, it lost all contact, probably succumbing to the crushing pressure, and was followed in 1962 by Mariner 1(NASA), which also faced the same fate. But Mariner 2 became the first successful Interplanetary mission, and reached within 34,833 km of Venus’s surface, and recorded temperatures upto 698 Kelvin, which removed any possibility of lifeforms existing on the hellish world. In 1966, Venera 3, Soviet’s second attempt to win over Venus, became the first man-made object to enter the atmosphere and touch the surface of another planet when it crash landed on Venus. Later, NASA’s Magellan orbiter, Soviet’s Venera 7 and Venera 9, Pioneer 1 and Pioneer 2, among others also visited the planet, and returned ample amount of data and pictures.
Though Venus also has a molten iron core like Earth, with a hard crust, it has no magnetic field, possibly due to its slow rotation rate. Combine the lack of magnetic field with a very thick atmosphere containing carbon dioxide and liquid sulphuric acid, the greenhouse effect is so high that despite being twice as far from sun compared to Mercury, it is the hottest planet in the solar system. The temperature range between 400 to 740 Kelvins, and reach up to 1000 Kelvins in infrared at some places when it rains-Sulphuric Acid! The atmospheric pressure is 90 times higher than that in Earth, enough to crush the first attempts to study it by Venera 1 and Mariner 1. Images returned by Pioneer 13 show that 80% of the planet is covered with molten lava, and volcanic eruptions is a commonplace. The planet though shows no tectonic movement, unlike Earth, which means instead of releasing pressure from the mantle below through the collision of tectonic plates, volcanoes help in distressing the planet. It is believed to have been covered by water earlier, which eventually boiled off. Extensive study of the planet can hence help us understand why despite of all the similarities, did the two sisters, Earth and Venus, evolve so differently. The two poles of the planet also show ‘vertical’ vortexes which can be up to 350 kph fast in the upper atmosphere, while just a few kilometres per hour fast near the surface. The planet has no moons or rings. Though Cassini, for once thought Venus had a moon, which later turned out to be Jupiter.
The surface of Venus as seen in the above images, is clearly dry, rocky with cracks all over due to the harsh conditions. There are many small volcanic mountains on the planet like Maat mons, Sif mons, and gula mons. It has highlands like the Aphrodite terra, Ishtar terra, and vast plain lands like Atlanta plantia, Guinivera plantia and Lavinia plantia. The craters of the Coronae. and the collapsed domes Pancake, are well known features of the planet. Below are some images and 3-d pics generated through data from radars and images returned by the landers other missions.
A lot is yet to be known about our neighbour. The Venus In-situ mission by NASA in 2022 aims to study more of Venus’s surface and the events taking place there. Many advise that the planet should be ‘terraformed’ to make it habitable for us to live, while some go even further to suggest making it collide with asteroids to blow of its atmosphere considerably. While some suggest that we could travel to Venus and stay in special ‘floating cities’ that are covered in a protective barrier between them and the toxic atmosphere. Amongst many posters made public by NASA to encourage space travel and studies, included one to travel to Venus, (pictured below) showing the idea of floating cities. While visiting Venus seems even more far fetched dream than living in Mars, terraforming it might be possible for a Earth atleast a century in the future, all in good time! Nevertheless I am not very eager to pay a visit to the land of nightmares anytime soon.
This was the first post in my attempt to learn more about space and share it. I am sure this section of my blog will surely be a dear one and will also be enjoyed by others. Till next time, Happy Reading!
-The Cosmogasmic Person
Images adopted from NASA website.