Before humans appeared, the world was completely different. Our planet has not always looked the way it does now. Over the past 4.5 billion years, it has gone through incredible changes that you could never imagine. If you could go back and visit Earth millions of years ago, you would see an alien planet that seemed straight out of the pages of a science fiction book.
1. Giant mushrooms grew all over the planet
Approximately 400 million years ago, trees were approximately up to a person's waist. All plants were much smaller than today - except for mushrooms. They grew 8 m in height, and their leg (or is it the trunk?) was 1 meter in diameter. They did not have the large caps that we associate with mushrooms today. Instead, they were just pillars sticking out. But they were everywhere.
2. The sky was orange and the oceans were green
The sky wasn't always blue. About 3.7 billion years ago, it is believed that the oceans were green, the continents were black, and the sky looked like an orange haze. The oceans were green because iron dissolved in sea water, leaving green rust. The continents were black due to the lack of plants and lava cover. The sky was not blue because instead of oxygen it was mostly methane.
3. The planet smelled like rotten eggs
Scientists are confident that they know what our planet once smelled like. And it had the distinct smell of rotten eggs. This is because 2 billion years ago the oceans were filled with gaseous bacteria that fed on salt and released hydrogen sulfide, filling the air with a stench.
4. The planet was purple
When the first plants appeared on Earth, they were not green. According to one theory, they would be purple. It is believed that the first life forms on Earth partially absorbed light from the Sun. Modern plants are green because they use chlorophyll to absorb sunlight, but the first plants used retina - and this gave them a bright violet hue. Purple may have been our color for a long time.
5. The world looked like a snowball
We all know about the Ice Age. However, there is evidence that one of the ice ages 716 million years ago was quite extreme. It's called the "Snowy Earth" period because the Earth may have been so covered in ice that it literally looked like a giant white snowball floating in space.
6. Acid rain fell on Earth for 100 thousand years
Eventually, the period of the Snowy Earth ended - and in the most terrible way imaginable. Then “intensive chemical weathering” began. In other words, acid rain was constantly pouring from the sky - and so on for 100 thousand years. It melted the glaciers covering the planet, sent nutrients into the ocean and allowed life to arise underwater. Before life began to appear on Earth, the planet was a toxic, inhospitable desert.
7. The Arctic was green and densely populated
About 50 million years ago, the Arctic was a completely different place. It was a time called the Early Eocene Epoch, and the world was very warm. Palm trees grew in Alaska, and crocodiles swam off the coast of Greenland. The Arctic Ocean was likely a gigantic body of freshwater, teeming with living things.
8. Dust blocked the sun
When an asteroid crashed into Earth 65 million years ago and wiped out the dinosaurs, the chaos didn't end. The world has become a dark and terrible place. All the dust, soil and rocks rose into the atmosphere and even into space, shrouding the planet in a huge layer of dust. The Sun disappeared from the sky. This did not last long, but even when the huge cloud of dust disappeared, there remained in the stratosphere sulfuric acid and fell into the clouds. It's time for acid rain again.
9. It rained liquid hot magma
However, the previous asteroid was child's play compared to the one that crashed into the planet 4 billion years ago and turned it into a hellscape. The oceans on the planet began to boil. The heat from the asteroid impact effectively ended the first oceans on Earth evaporating. Huge parts of the Earth's surface have melted. Magnesium oxide rose into the atmosphere and condensed into droplets of liquid hot magma, which fell as rain.
10. Giant insects were everywhere
About 300 million years ago, the planet was completely covered with lowland swamp forests, and the air was filled with oxygen. 50% more oxygen than today, and this created an incredible explosion of life... and the appearance of huge and scary insects. For some creatures, the oxygen in the atmosphere was too abundant. The small insects could not cope with this, so they began to actively increase in size. Scientists have found fossils of dragonflies that were the size of a modern seagull. By the way, they were most likely carnivorous predators.
Our planet is more than 4.5 billion years old. At the moment it appeared, it looked completely different. What was there in ancient times on the territory modern Russia, and how it has changed over the years - in the book “Ancient Monsters of Russia”.
3000 million years ago
In the first millions of years of its life, the Earth was like hell. There was constant acid rain here, and hundreds of volcanoes erupted. There was a lot more asteroids. Endless meteorite showers formed the planet - they crashed and became part of it. Some meteorites reached the size of modern cities.
One day, the Earth collided with another planet, one part of which joined us, and the second flew into orbit and over the years turned into the modern Moon.
Illustration from the book
3 billion years ago, a day lasted only 5 hours, and there were 1500 days in a year. Happened once every 50 hours moon eclipse, and once in 100 - sunny. It probably looked very beautiful, just admire natural phenomena there was no one back then.
The science
Today, our neighbor Mars is a cold, red-desert planet. Liquid water no longer exists on its surface due to low atmospheric pressure and temperature. However, there is evidence that streams once flowed along its surface brackish liquid with a low freezing point.
Water on Mars modern conditions can be ice, or can turn into steam, bypassing the liquid state.
Ancient Mars
It turns out that approximately 4 billion years ago When Mars was a young planet, its atmosphere was denser and its surface was warm enough to support liquid water, which is very an important condition for the existence of life.
On the surface of Mars, as on the surface of the Earth, there are characteristic branched channels, which were formed by fluid flows. In the interior of some impact craters there are pools in which lakes once splashed.
Small craters disappeared over time, while larger ones retained signs of erosion. The water destroyed the rocks around 3.7 billion years ago. Layers of sediment are visible on the walls of the craters. There are also minerals that could have formed exclusively in the presence of water.
The animation presented in the following video shows what the Red Planet might have been like in those distant times when on its surface liquid water existed. Fast moving clouds symbolize the passage of time. A gradual transition from a warm and humid to a cold and dry climate is shown. The lakes dry up and freeze, and the sky changes color from soft blue to dirty pink:
It is not yet clear exactly is it long enough whether a favorable climate remained on Mars and whether life had time to arise on it during this time.
The earliest signs of earthly life presented as an organic chemical structure found in rocks on the island of Greenland. These rocks were once on the seabed. Approximate age of the structure – 3.8 billion years, that is, after the formation of our planet, only 700 million years. No fossilized remains of life that date back to this period have yet been discovered.
Fossils of actually existing microorganisms, according to some estimates, 3.5 billion years. By that time, conditions favorable to the emergence of life had already disappeared on Mars.
Comparisons between the histories of the two planets should be made with caution, the researchers warn, as chemical composition The surfaces of Earth and Mars are different, as is their volcanic activity.
How did life begin on Earth?
The earth appeared approximately 4.5 -5 billion years ago from cosmic dust and at first it was a hot ball.
The ancestor of all creatures living on our planet was called Last universal common ancestor. He lived approximately 3.5-3.8 billion years ago. This ancestor cannot be considered the first living creature of our planet.
There are several hypotheses for the origin of life on our planet, including the spontaneous generation hypothesis and the bringing life from space, including from other planets, for example, from Mars.
According to one of the most popular versions, life on Earth appeared after it was enough liquid water and special climatic conditions developed.
The first living creatures were prokaryotes, single-celled creatures without a formed nucleus. These creatures looked like modern bacteria. Living organisms have evolved and become more complex over the course of many millions of years.
- 1000-600 million years ago there were already jellyfish, mollusks, echinoderms, polyps and flatworms on Earth.
Appearing in ancient ocean, some animals gradually began to make their way onto land, while others remained floating in the water. This happened 416-360 million years ago V Devonian period.
Illustrations by Simone Marchi for a research paper in the journal Nature.
NASA scientists have reconstructed the events that took place at the very beginning of the existence of our planet. The Earth, during its formation period from 4.5 to 3.5 billion years ago, was a hot ball, subject to continuous bombardment by extraterrestrial bodies. Its oceans evaporated, turning into steam, cracks appeared in the still young crust, and the surface was filled with lava.
Very little has survived that could be used to reconstruct a picture of what was happening. There are virtually no rocks older than 3.8 billion years left. The only evidence from the distant past is some zircons less than one millimeter in size contained in volcanic rocks. Radioactive decay data estimates their age to be 4.4 billion years.
Studying the distribution of zircons on Earth provided the researchers with a way to calibrate computer simulations.
Also, in order to learn more about the period immediately after the formation of the Earth, scientists used geological data from the Moon and other objects solar system.
Computer model showed that the Earth, in addition to surviving collisions with many small and medium-sized asteroids, most likely also collided with several truly large objects, melted the entire surface of the planet. This theory suggests that the Earth's surface melted several times, but significant periods of time may have passed between these collisions. And if life arose on Earth, it had to be able to withstand high temperatures and hide deep under the surface.
After a billion years of bombardment, lava eruptions and ocean evaporation, the first hypothetical supercontinent of Vaalbara formed, which subsequently broke apart. This happened approximately 2500 million years ago. The name Vaalbara comes from the names of Kaapvaal's procontinents South Africa and Pilbara in Western Australia. The migration routes of the Kaapvaal and Pilbara procontinents further indicate that they were once connected. This is confirmed by geochronological and paleomagnetic studies, which show that the procontinents experienced a circular transverse separation at an angle of 30°, after which they no longer touched.
People are sure that the Earth's satellite is the only space object that appears in the night sky. However, after studying ancient sources, scientists found that three moons illuminated the Earth 4 billion years ago before the destruction of two celestial bodies by cosmic disasters.
Ancient German mythology calls the human world Midgard, which was protected by celestial bodies from the dangerous effects of space. Thanks to the force of gravity, they could slow down the rotation of the Earth, increasing the length of the day. Experts have long been interested in this phenomenon, and researchers have suggested that the moons were created by highly developed creatures with unique technologies. There is in the Vedas detailed description the death of Lelya, which was located closer than other objects to the planet.
This happened 122,000 years ago, when its surface was invaded by a civilization of aggressive aliens who decided to capture earthlings. They built on it military base, but the ancestors noticed the threat in time and destroyed the enemy, but the fragments of the destroyed satellite after the fall became the reason for the emergence of the first Flood And ice age. North hemisphere became covered with snow, and people and animals were forced to move beyond the Ural Mountains.
In memory of such events, the Slavs celebrated the Easter holiday, where a tradition arose of testing the strength of colored eggs. The strongest of them was a symbol of the power of Dazhdbog, and the broken analogue personified the Moon destroyed by evil forces and was always given to animals to be devoured. Fatta was the second satellite of the planet and saw the greatness of Atlantis. But the insatiable thirst for power of a disappeared civilization, which used the forces of the elements during the creation of its destructive technologies, led to a disruption of the cosmic balance.
The satellite left orbit, and the Earth began to rotate faster around its axis, after which the year increased by 5 days. The Mayan calendars preserve information about a strong impact after the collision of celestial bodies, which shifted tectonic platforms. Oceans and seas overflowed their shores and began to sweep away everything in their path, while ancient volcanoes awakened and new ones formed natural objects rising from the bowels of the earth. Ashes covered the Sun and caused new ending light, described in all religions.
Humanity was thrown back into the Stone Age and again learned to survive in unusual conditions after a planetary catastrophe. Modern scientists are sure that the missing Moons had natural origin, because they found a huge “sky field” while exploring the Argentine region of Campo del Cielo. Indian legends tell of a huge ball that fell from the sky, and the Spaniards made weapons from a piece of cosmic iron.
In the 16th century, a local resident also took material from here for personal needs, after which she arrived here. scientific expedition together with Don Rubin de Celis. Archival documents They recorded a meteorite weighing 15 tons, only then it disappeared without a trace. Another cosmic fellow was found in 1803, and a piece of the gift from heaven was bought by the Briton Woodbine Darish, who gave it to the museum staff. Until now, archaeologists are faced with a large accumulation of celestial bodies and craters in a 17-kilometer area that intrigued the American scientist Cassidy.
When he found a lot of small debris here celestial body made of 100% iron, I immediately noticed something strange. When a meteorite explodes, pieces can only fall into a 2-meter area, which cannot be said about this area. After analysis, the expert concluded that it was the missing second Moon, which was attracted to the Earth to the Roche limit, after which it fell apart.
The fire, caused by the fall of debris from a celestial body, began 6,000 years ago, and in 2016, scientists noticed a quasi-moon that had been in Earth’s orbit for 100 years and was not going to leave it for several centuries. The asteroid has a 100-meter diameter and has become a satellite of the planet, approaching the Sun or hiding in its shadow, but it is not a threat to humanity.
