<Useless Miscellaneous Thoughts Series>

<Useless Miscellaneous Thoughts Series>

How special is the Earth as a condition for the birth of life?

The universal theory of life believes that life arises naturally if certain conditions are met in the universe. If this argument is correct, what is the 'constant condition' and how common is it? It can be seen that the likelihood of us discovering extraterrestrial life is determined.

We have no choice but to consider an environment similar to Earth as a condition because the only life we know exists on Earth. We are looking for rocky planets in the Goldilocks Zone in the outside world and analyzing their atmospheric composition. Quite a few of these exoplanets have been discovered.

Then we have no choice but to go back to Mars once again to see if the conditions are right.

As Mars progressed, it became more embarrassing that there were no signs of life on the planet. Mars is now a barren and desolate place, but it has been confirmed that there were atmospheres, seas, rivers, and magnetic fields a long time ago. At that time, the environment was almost no different from that of Earth. Nonetheless, life did not occur on Mars.

There is life on Earth, and it may be just a coincidence that Mars does not have it. But it may be because of some difference in conditions. If it's just a coincidence, there's nothing more to see, so we think about the conditions that make the difference between the two.

There may be many minor differences between ancient Earth and ancient Mars, but they are very similar in a broad sense. Except for one thing. That one thing is the existence of the moon. There is a very unique giant satellite called the moon on Earth. The moon is astronomically very abnormal. Usually, naturally, there are few satellites this large for the size of a planet.

To find out how strange the moon is, let's first look at the satellites of the planets in the solar system. The four rocky planets between Mercury and Mars, commonly called inner planets, have no significant satellites except the moon. (There are no Mercury or Venus, and the diameter of Phobos and Dimos on Mars is 0.3% of that of Mars.)

The four gas giants, called exoplanets, generally have the largest satellites with a diameter of 3-5% relative to the planet's diameter. (This ratio can be judged to be a general combination between planets and satellites, given that the four are quite similar.)

The moon, by the way, boasts a large scale that is 27% of the Earth's diameter. Scientists have been investigating for a long time why there is such an abnormal large satellite on Earth, and now they have generally reached a clear conclusion. If you look at the cause, it is very rare and unusual.

In other words, strangely, two planets were formed in the same orbit in the early days of the formation of the solar system. The two planets that were orbiting in the same orbit collided with each other, and as a result, they became a large Earth and a small moon and stabilized. In other words, the early environment of the Earth was formed through a process that is not common in space.

Additionally, the moon's tidal effect is affecting the Earth's oceans and atmosphere, as well as the liquid flow inside living things. We cannot rule out the possibility that this has had a significant impact on the birth of life.

It is a brain statement that the existence of the moon may be a condition for the birth of life. However, it is also the biggest difference between ancient Mars and Earth. If the existence of a giant satellite, or two planets in the same orbit and the conditions under which it collided, is one of the important facts of life's birth,

Even in our galaxy, the conditions for the birth of life will be a very special and rare case, which will make our efforts to find extraterrestrial life even more difficult to answer.