Do you know what would happen if all the planets in our solar system were in the habitable zone? Would life form on them and evolve? According to researchers from DLR, the answer is yes. Their simulation of the habitability of different exoplanets shows that some of them are habitable around their host star. If we had more earth-like planets in our solar system, there might have been multiple locations for life to develop and colonize.
What would have happened with our previous earth-like planet, probably covered by water billions of years ago, if this is true? The closest one could get to Earth’s orbit would be Venus which is not good news for future colonization ideas. But hopefully, discoveries will help us find more earth-like locations that can support life without being covered by water or lava. Read on to learn more about this fascinating topic.
What If Our Solar System Planets Were in the Habitable Zone?
Life could have flourished in the hypothetical situation where all the planets were in the habitable zone. The habitable zone of an exoplanet is the distance from a star where a planet is neither too warm nor too cold for liquid water to exist on the planet’s surface. The habitable zone of our Sun lies between about 0.95 and 1.35 AU (AU is the Earth-Sun distance, about 93 million miles).
While it appears that Venus and Mars are too hot for water to exist on their surface, researchers found that in their computer simulation, the temperatures would have been just suitable for liquid water. So why are the other planets in our system not suitable for life?
Mercury and Dwarf Planets May Be Habitable
Mercury’s orbit is very close to the Sun, with an average distance of just under 38 million miles. This planet is so hot it’s crushingly dense and most likely uninhabitable. However, there are theories that Mercury may still have an ocean of liquid below its surface. It would make it a good candidate for the development of life since it would be able to sustain life in a hydrothermal ocean.
The conditions are not exactly right for life on dwarf planets, such as Pluto and Ceres, but they may be good enough. Ceres is covered in ice, like Pluto. However, it has enough heat coming from the Sun to be not too cold. Ceres may have enough heat to support life and may even be the best candidate for colonization in our solar system.
How Many Earth-Like Locations Are There?
There are billions of planets in the universe, and at least one could be Earth-like. With all the technology we have, it would only take a few years to find another planet with a habitable zone for life. But for life to develop, there has to be liquid water. So, we can assume that most planets in the habitable zone are water-covered planets.
If all the planets in our solar system were in the habitable zone, then there must be many more water-covered planets we don’t know about. That being said, astronomers have not yet found any Earth-like planets, even in the distant part of the galaxy that we know has many habitable locations. Hopefully, they will find one soon.
Why Venus is Not a Good Location for Colonization
The greenhouse effect of Venus is so intense that it can make the temperature hot enough to melt ice on the planet’s surface. If you could somehow melt enough of the ice and build a greenhouse, you could have a way to feed your people. However, the more significant issue with Venus is that it is so hot that it is uninhabitable.
The temperature on the surface of Venus is about the same as that of most other planets, except it’s so hot that it’s uninhabitable. The atmosphere of Venus is too thick for humans to survive without protection.
Venus is Too Hot for Human Life
The surface temperature of Venus is almost 500 degrees Fahrenheit. How can we hope to have lived in such a hostile place? Well, it’s not impossible. Researchers found that the temperatures on Venus would be just right for liquid water to exist on the surface. It would be easy for water to be transformed into a gas or a solid under such conditions. These conditions would allow an energy source below the planet’s surface to provide heat to keep the water liquid.
Venus has lightning that could provide the electrical power needed for photosynthesis. Additionally, the greenhouse effect of Venus can make the temperature just right for plants to grow. So, the next question is, “can we make plants grow on the surface of Venus?” The answer is yes.
Habitability of Venus
The closest one could get to Earth’s orbit would be Venus which is not good news for future colonization ideas. As we all know, Venus is a scorching planet, and its surface pressure is 90 times higher than the sea level on Earth, which means that no form of life can exist on its surface. The temperature on the surface of Venus is around 480 degrees Celsius which is so hot that it would destroy any form of life.
An exoplanet’s habitability depends on its place in its star’s habitable zone. It is the region around the host star where a planet’s temperature is just right for water to be liquid. If we had a planet similar to ours with a thick atmosphere and a rocky surface, our colonization would be complex because we would not be able to survive on the surface.
Another critical factor is the angle of the star to the exoplanet. If the angle is greater than the critical angle, the exoplanet may be too hot to sustain life. On the other hand, if it is too cold, it may be in an environment without water.
How to Find Habitable Exoplanets
Finding Earth-like planets is the first step in finding a place for humans to live. The Kepler Space Telescope looking for new exoplanets has found many candidate locations, but they have all been too far or too small to be habitable. New technologies can allow astronomers to examine more distant or more minor planets, so there is a chance that one of them will be inhabited by life as we know it.
Some missions plan to land on exoplanets and take data to see what they are like. Some of these missions are planned to launch shortly. These missions may take years to reach their destination and take years to analyze the data they collect. So, we can only wait and see what discoveries are made shortly.
Earth-Like Conditions For Life
Let’s start with a few essential facts about the habitability of the Earth. It is the only planet known to have life on it. Our current conditions are suitable for sustaining life too. It includes liquid water on the land surface. About half of the Earth’s surface is covered with water. Now, as we know, liquid water is necessary to sustain life. But it is not sufficient. It would help if you also had an atmosphere containing water vapour, oxygen, noble gases, and other trace elements to sustain life.
Mars Has A Desert Climate and Can’t Support Life Either.
The first thing that comes to our mind is the possibility of life. Let’s start with the red planet. It is the first place most people think of when it comes to a planet’s habitability. However, the presence of liquid water on Mars today is doubtful. As of now, scientists are not even sure if there was liquid water on the red planet billions of years ago. If there was liquid water on the red planet billions of years ago, then it may have been suitable for life to develop.
We know that Mars shares many characteristics with Earth if we think about our planet, but it is far less habitable. It is a dry, desert planet with almost no water, air, or soil. Mars is not in the star’s habitable zone that lights it up, and it is too far away to receive any help from the Sun. But due to the low pressure, low temperature, and the presence of toxic elements like perchlorates, it is doubtful that life could have evolved there.
Jupiter Has a More Suitable, Temperate Climate
Jupiter is an excellent planet for many reasons; one of them is its high water content and the fact that it is far away from our star and is therefore not very hot. The critical thing about Jupiter is that it is not in the habitable zone of our Sun, which means that it is so far away from the Earth that the slightest influence from our star would make it difficult for life to develop.
Suppose we had a place covered in water and was close to Jupiter, which is an ideal place to settle? The answer is yes, according to researchers from DLR. However, the density of the gases found in Jupiter is very similar to those found in our atmosphere, giving it a breathable potential.
Their simulation of the habitability of different exoplanets shows that some of them are habitable around their host star. If we had more earth-like planets in our solar system, there might have been multiple locations for life to develop and colonize.
Saturn Has An Unsuitable Environment
The gas giant planet lies much further away from the habitable zone than Mars. It is so far that it would take many years to reach it, and the return trip would be difficult too. The situation would be even worse if we think that the temperature of Saturn is far lower than that of our Sun and would not be helpful at all for the development of life.
Even the presence of water on the surface of Saturn is doubtful. The best way to think about this would be as a place to look for primitive forms of life that have spent billions of years in the dark and cold, undetectable from the surface.
Habitability of Jupiter’s Moon Europa
The surface of Jupiter’s icy moon Europa is covered in a thin layer of ice. It is this layer that makes it possible for life to exist there. If life had evolved on the surface of Europa, then it would have survived even the extreme conditions of Jupiter. The habitability of Europa depends on its distance from the Sun.
The farther it is from the star, the longer the period that the ice on Europa is expected to survive. If life did evolve on the surface of Europa, then it would have formed by the action of oxygen on iron rocks. It may have happened a very long time ago, maybe billions of years ago. It is why scientists think that Europa is suitable for liquid water.
Scientists have also discovered that the ice on Europa is much younger than the surrounding rocks. There is a possibility that the water may have come from below the surface of Europa, where there are chasms that may have water that could have been brought to the surface by geological processes.
Habitability of Saturn’s Moons Titan and Enceladus
Titan is the only moon of Saturn known to have an atmosphere. The other two moons, Enceladus and Titan, share the same fate. They are also in the habitable zone of their host star, have an ice-covered surface, and most importantly, they are small enough to have a rocky interior, like the Earth.
Enceladus is an exciting place to consider as it is one of the best candidates for the potential emergence of life. Its ocean is composed of hydrothermal water, which could have been brought to the surface by geological processes. The chances of life forming in such a place are much better than in the case of the larger moons of Jupiter.
Habitability of Neptune’s Moons Triton and Pluto
Pluto and Triton are small icy moons located in the outer part of the Neptune system. Triton is more extensive than Pluto and has a retrograde orbit, which means that it is moving in the opposite direction of Pluto. It means that it is close to Neptune, and it is also small enough to be pulled into the Neptunian orbit.
The interior of Triton is rich in volatiles, which could make it a good candidate for colonization. The interior of Pluto is similar to that of meteorites, which makes it a possible candidate for colonization.
Uranus and Neptune Could Become Habitable
If you placed all the planets in our solar system in our star’s habitable zone, Uranus and Neptune would be warm and probably have liquid water. Uranus is almost precisely between the orbits of Saturn and the Sun, and Neptune is almost precisely between the orbits of Saturn and the Sun.
It could be because stars are an essential part of the temperature of a planet. Planets in habitable zones orbit their Sun because they have a band around them that is just right for water to exist on the surface. If a planet is too close (like Mercury is to the Sun) or too far (like Uranus is from the Sun) from this band, it will not have liquid water on the surface.
What If All the Stars in the Universe Were in Their Habitable Zones?
If you look at all the stars in the universe and find out which ones are in the habitable zones of their respective planets, you will be surprised to learn that there are probably a lot of stars in our galaxy that are in their habitable zones! The habitable zones of many stars are very close to being in the right temperature band for water to exist on the surface of a planet.
It means that if we could find a way to move our planets to a different star, we might have a chance of making these planets more habitable. You could look for a new star that we could move our planets to that is just a little bit closer to the Sun and much less massive, or find a new planet that we could move into the habitable zone of our new star. The closest star that could support life may be Sirius B, but it is too close to the size of our Sun.
Sirius B is only about twice as massive as our Sun and twice as distant from us. That means that to live on the surface of this small planet, you would need to be about one meter tall. It is not very feasible!
The Moon Would Be Too Hot to Support Life
Earth is exceptionally close to the temperature required to make water into liquid form, but the temperature would be too hot to allow life to form. The moon would be too hot to support life. It is so close to the Earth that it would have the same temperature as the Earth. A habitable zone around the Earth would be too hot for life to exist.
What Would Happen if You Placed Every Planet in Its Habitable Zone?
If you placed every planet in the solar system in its habitable zone and took each one out of its current orbit, you would find that many of them would most likely not have liquid water. If you placed all the planets in the solar system in our star’s habitable zone, only 5 would have liquid water. It would not make sense because all other planets could also be in a habitable zone.
Most of these planets would be too hot and would not support life. Some would be in the right temperature band for water to exist on the surface, but they would be too close to their star to have a chance of life.
The next step in the colonization of our solar system would be to look for another earth-like planet and make a permanent settlement there. Living on another planet would be a challenge for any species that have lived on Earth, but with time and ingenuity, we could do it.
The idea of all the planets in our solar system being in the habitable zone sounds exciting and could be accurate, but we must remember that we are very different from other life forms. It would be not easy to survive on another planet with very different conditions. We have to remember that the Earth is our only home, and we shouldn’t mess around with finding other planets to live on.
If we do that, we could end up like the dinosaurs, who had to find another planet to live on when their planet became too hot or too cold for them.
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