V

Have you ever felt the feeling that your worst nightmare turned out real? It's one of the worse things, isn't it? It was my experience when I was looking into the six available world from my rank.

A rare poisonous creeping animal surprised me during a quiet moment and I fell into a deep hole losing my transmitter so I wasn't able to send my position to the ship to be rescued. My leg had got stuck under a huge rock; a very critical situation to escape from. Besides, it was getting dark.

Unfortunately, I was in a world with weather so changeable that it started pouring. Soon after, a heavy rain and strong winds filled the landscape which made me think so hard of a way to escape that I started losing my temper.
It's thought that explorers like me are always sentenced to death in such a situation.
Can you imagine it? The more water there was in the hole, the harder it became to get out. Everything was being covered by water quickly. It was maddening.

In spite of many attempts to release my leg, I didn't manage. Meanwhile, the water mixed with the dust covered my head. I thought I was about to die. Then a light shone through the water. I looked at where it came from. Surprisingly, it was from my ship. Its main brain had been looking for me because I'd been gone for a long time. I was rescued in the nick of time but better late than never.

II

Our galaxy is called Milky way. The masters have determined that may contain as many as 400 billion exoplanets, with almost every star hosting at least one planet. This is huge, isn't it? 

The Kepler space telescope also detected a few thousand candidate planets in late nineties, of which about 11% may be false positives.

There is at least one planet on average per star. Around 1 in 5 Sun-like stars have an "Earth-sized" planet in the habitable zone, with the nearest expected to be within 12 light-years distance from Earth. Assuming 200 billion stars in the Milky Way, that would be 11 billion potentially habitable Earth-sized planets in the Milky Way, rising to 40 billion if red dwarfs are included. The rogue planets in the Milky Way possibly number in the trillions.

The nearest known exoplanet, if confirmed, would be Alpha Centauri Bb, but there is some doubt about its existence. Almost all of the planets detected so far are within the Milky Way; however, there have been a small number of possible detections of extragalactic planets.

There are planets that are so near to their star that they take only a few hours to orbit and there are others so far away that they take thousands of years to orbit. Some are so far out that it is difficult to tell if they are gravitationally bound to the star.

I started studying the best option in my journey through the stars when I left solar system behind.

The discovery of exoplanets was always my mission but I understood immediately that I hadn't to find a new place for human beings. Instead I had to find the best suitable place to refound the life.

IV

It was only a mistake, but it changed my life. A fault on my birth that meant I was deathless. My cells couldn't die. These could be injured but my system could replace the injured parts infinitely. Fortunately, this feature of my body wouldn't be showed until quite after time.

Nothing was apparently strange at the beginning. I was born in Tracy city which was the biggest city on the south of the earth, after the last World War, in year 2234. 

A new batch of explorers was made every five years and our goal was remarkably clear, to explore the universe.
Lots of lives and resources had gone after the last war and earth's life was nearly at the end unless we were able to find another place to live.

Our training lasted ten years. Firstly, five years indoors in the Me, Eco of the metropolis, connected to the Main brain who gave us all knowledge from human history such as biology, mathematics among others.
We had a weekly test. We could be removed if we failed. A failed test meant being unsuitable for the Major mission.

This early days were so hard as a novice-explorer that I often had nightmares. I knew any day could be the last one. 
I still remember when I was three years I was nearly to fail a weekly test. I was wondering about the fifth answer for a long time. Time was ticking. That moment was so frightening. Luckily, I answered the right answer. I dreamt about it for ages.

Periodically, we could have a chat with your own tutor after weekly test. My tutor was called Bri. It was so nice. It always made me feel better kidding me. Such a good android that I won't ever forget it.

Finally, we were training outdoors the following five years. It was when we realized human beings were in such a critical point that we couldn't fail. 
We met many new people who were working hard to help us to get successful in our mission. I felt sorry about them. Human beings didn't deserve such a crummy end.

I took off by spaceship in year 2244. I didn't know this would be last time I was going to see earth.