I am continuing to look at the positioning of the earth in the solar system. This Nugget I want to look at the facts from a different, slightly quirky perspective. I am sure we have all heard the statement that “Men are from Mars and women are from Venus.” Where does that idea come from? It comes from the book of the same name written by John Gray. Gray was not looking at the solar system and the positioning of the earth in the solar system. He used that clever title to investigate the relationships between men and why we are so different.
Why did Gray choose Mars and Venus to illustrate his point? Simply because they are the two closest planets to earth and with associations to men and women. Venus in numbers of ways that I won’t elaborate has connections in our culture and in ancient world with women and Mars similarly with men. From my point of view in this study of earth being perfectly positioned for life, it is logical to look at our two closest neighbours, Venus and Mars. Venus is one click closer to the Sun than the Earth while Mars is one click further away. If we are the third rock from the Sun, then Venus is the second and Mars is the fourth. It all makes sense, doesn’t it? After all NASA and others are spending billions in their search for extra-terrestrial intelligence (SETI) and we have this notion popularised by space travel and numbers of entrepreneurs these days that maybe, just maybe someone can “fly me to moon” or maybe yet we could colonize Mars or Venus. After all, Matt Damon grew food on Mars in the movie The Martian. It’s all possible, right?
Mars is 54.6 million kilometres further away from the earth and further away from the Sun. Venus on the other hand is 41 million kilometres from the earth and closer to the Sun. Just let those facts sink in for a moment. Think of them in the context of the delicate balance of Earth and its relation to the Sun and the ability to sustain life on this planet. Imagine for a moment what life on either Mars or Venus must be like. Let’s investigate. First we will move closer.
Venus
Some Facts About Venus
Venus is the second brightest natural object in the sky. The planet has an apparent magnitude of -3.8 to -4.6, which makes it visible on a bright, clear day. The Moon is the only other natural object that is brighter. One day on Venus is longer than one year. Due to the slow rotation on its axis, it takes 244 Earth-days to complete one rotation. The orbit of the planet takes 225 Earth-days – making a year on Venus shorter. Venus is sometimes called Earth’s sister planet. This is because their size is very similar (there is only a 638 km difference in diameter) and Venus has around 81% of Earth’s mass. They are also similarly located with Venus being the closest planet to Earth. Both planets also have a central core, a molten mantle and a crust. Venus has no moons nor rings. Venus rotates in the opposite direction to other planets. Most other planets rotate counter-clockwise on their axis, however Venus, like Uranus, rotates clockwise. This is known as a retrograde rotation and may have been caused by a collision with an asteroid or other object which caused the planet to change its rotational path.The temperature on Venus doesn’t vary much between the night and day. This is due to the slow movement of the solar winds across the surface of the planet. The atmosphere on Venus is a combination of carbon dioxide and nitrogen. There is a build up of infra-red light in the atmosphere of Venus which can’t be released. The heat from the sun is being trapped in the atmosphere of Venus and so the planet is getting hotter. These temperatures are enough to melt lead. Venus is the hottest planet in the solar system with an average surface temperature of 462°C (863°F). Also, Venus doesn’t tilt on its axis which means there are no seasons either. The atmosphere is a dense 96.5% carbon dioxide which traps heat and caused the greenhouse effect which has evaporated any potential water sources. Clouds of sulphuric acid float in an atmosphere of carbon dioxide and nitrogen. The atmospheric pressure of Venus is 92 times stronger than Earth’s. This means that any small asteroids entering the atmosphere of Venus are crushed by the immense pressure, which is why there are no small surface craters on the planet. This pressure is equivalent to being around 1,000 km under Earth’s oceans. Venus has a very weak magnetic field. This surprised scientists, who expected Venus to have a magnetic field similar in strength to Earth’s. One possible reason for this is that Venus has no solid inner core, or that its core is not cooling. Venus is the closest planet to Earth. When Venus is in line with Earth and the Sun, it is the closest planet to us, at an average distance of 41 million kilometres (25.5 million miles) away. The winds on Venus blow constantly at hurricane force. The effect of this is that the atmosphere of Venus is driven around the planet every four days. Venus experiences massive erosion and huge dust clouds. Venus is highly volcanic and volcanic activity has replaced the surface of the planet. Erosion is aided by the dense atmosphere and highly corrosive constituents which wear down the rock surface quickly with constant hurricane force winds which blow the huge amounts of dust and rock particles into the objects on the surface of the planet, eroding them rapidly.
And now a click further away . ..
Mars
Some Facts About Mars
Mars and Earth have approximately the same landmass. Even though Mars has only 15% of the Earth’s volume and just over 10% of the Earth’s mass, around two thirds of the Earth’s surface is covered in water. Martian surface gravity is only 37% of the Earth’s (meaning you could leap nearly three times higher on Mars).
Mars is home to the tallest mountain in the solar system. Olympus Mons, a shield volcano, is 21km high and 600km in diameter. Evidence from volcanic lava flows is so recent many scientists believe it is still active.
Mars has the largest dust storms in the solar system. They can last for months and cover the entire planet. Indeed in 1971 and 2001 Mars was covered by a dust storm which lasted the entire year. The seasons are extreme because its elliptical (oval-shaped) orbital path around the Sun is more elongated than most other planets in the solar system.
On Mars the Sun appears about half the size as it does on Earth. At the closest point to the Sun, the Martian southern hemisphere leans towards the Sun, causing a short, intensely hot summer, while the northern hemisphere endures a brief, cold winter: at its farthest point from the Sun, the Martian northern hemisphere leans towards the Sun, causing a long, mild summer, while the southern hemisphere endures a lengthy, cold winter.
The rotation of Mars is similar to Earth at just over 24 hours for one day. Given the distance of Mars from the sun it takes approximately two earth years to complete one orbit around the sun. Mars is tilted 25 degree from vertical as compared with Earth’s tilt of 23 degrees. Mars lies just outside the goldilocks zone in terms of distance from the sun to allow water to exist in liquid form. The surface temperatures on Mars vary between – 65 to -120 0C. Mars does not have a magnetic field leading scientists to the conclusion the centre of the planet is solid and motionless. The absence of a magnetic field means Mars lacks protection against the deadly glare of cosmic rays and solar winds. Mars essentially is a dead planet. Having no protective magnetic field means that Mars is pitted with impact craters from frequent meteor showers. Mars atmosphere is thin and not easily retained. It is made up of carbon dioxide, nitrogen and argon. At the coldest time in Martian year carbon dioxide condenses and covers a large part of the planet with carbon dioxide frost. Mars experiences massive dust storms which cover the entire planet for long periods of time. The atmosphere of Mars is most often hazy and shrouded in dust. Mars has two small moons one of which, Phobos, orbits three times a day and is only 6,000 kms from the surface of Mars. The more distant moon, Deimos, takes 30 hours to orbit the planet. The orbits of these two moons have the potential to produce gravitational conflict but without any water on the surface there are no observable effects.
If you are interested in a trip to Venus or Mars I am sure Elon Musk could arrange it. The only problem is you would die before you get there and if not, the visit no matter how short would kill you.
The possibility of men being from Mars and women being from Venus has just faded from the realm of reality. While it might be an appealing idea to account for the tensions between the sexes, the notion does not hold out any hope of a colonization programme anytime soon.
Men are from Earth; women are from Earth. Get used to it and be grateful you live on a habitable planet.