Hello, earthlings!
I'm Alan, and I live in the same Solar System as you do.
But the chances we'll ever meet are almost non-existent since your and my Solar Systems
exist in parallel worlds!
And in my world, people do NOT live on Earth because our Sun is twice smaller than yours!
What's the connection?
Grab some popcorn, I'll tell you a story.
You've probably never thought how much the way you live on Earth depends on the size
of the Sun!
And if at first sight, there seems to be no connection, let me surprise you!
The Sun in your world is a yellow dwarf: a perfect sphere of scorching plasma, generating
a magnetic field 24/7.
Despite being called a dwarf, its mass is 330,000 times bigger than that of the planet
you live on!
And the diameter of this giant is more than 864,000 miles.
(Do I sound like I'm envious?
That's because I am.)
But as you remember, in my world, the Sun is half the size of your star.
And it's a game-changer because this makes our Sun a red dwarf!
It happened many centuries ago: something went wrong, and our star started to lose its
mass.
After that, it grew cooler, darker, and eventually turned into a red dwarf.
In your universe, the closest red dwarf to your planet is Proxima Centauri, which is
around 4 light-years away.
These stars are long-livers of the Universe, and our Sun is likely to shine for another
several trillion years before it becomes a blue dwarf.
But despite such an optimistic scenario, when our Sun turned into a red dwarf, it meant
the end of life on our native planet, Earth.
You see, red dwarf stars are much colder than, let's say, yellow dwarfs.
And though our Sun used to have a temperature of 9,900°F (just like the Sun in your world),
after all the catastrophic changes, its temperature dropped to 6,400°F. That's why the habitable
zone around our Sun (meaning the region where liquid water could remain on the surface of
a planet) shrunk dramatically!
Sadly, Earth turned out to be out of the Sun's habitable zone.
Of course, people didn't feel the changes immediately.
The climate all over the planet was getting colder and colder, and astronomers' forecasts
were getting grimmer.
At first, it became impossible to live too close to the North and the South poles.
People started migrating closer to the equator.
Many animal and plant species were going extinct, despite all human attempts to save them in
special zoos and greenhouses.
Quite soon, half of the planet turned into an icy desert.
People had huge problems with food and other resources.
The overall temperature dropped to -18°F. Factories were straining to produce enough
warm clothes and electrical equipment to help people survive during the new Ice Age.
But even though the inhabitants of Earth hoped that the process would somehow reverse, the
situation was getting worse.
Every next day was darker than the previous one.
Dimmer sun meant that plants didn't have enough light to convert it into energy.
They started to wither, and animals that fed on them couldn't find food and disappeared
from the surface of the planet.
Panic and fear were enveloping Earth.
Even worse, this process was going much faster than it could - also due to the decreasing
size of the Sun.
The size of a star is directly connected with its gravity.
And since the Sun was becoming smaller, its gravitational pull on our planet was getting
weaker.
And it didn't take long until Earth changed its orbit to a wider one.
Now, it was moving even further from the Sun, receiving even less sunlight and continuing
to cool down.
Our planet and its inhabitants struggled a bit longer, but it was easy to predict the
outcome.
Finally, our beautiful Earth turned into a lifeless chunk of rock covered with a thick
layer of ice.
Ah, but I can guess what you're thinking now!
How come I'm still talking to you if my planet has become uninhabitable?
That's because, unsurprisingly, people don't live on Earth anymore.
With the Sun turned into a red dwarf, the Solar System we had known disappeared.
As you might remember, the star's gravitational pull decreased along with its size.
That's why the gas giants furthest from the Sun, like Uranus, Saturn, Neptune, and Jupiter,
simply drifted away!
And if you've just thought, "Hmm, is it such a big deal?"
let me explain something.
Saturn and especially Jupiter used to partially protect smaller planets, including Earth,
from asteroids!
Until these giants left the Solar System, they worked hard, catching big comets into
their gravitational field and then tearing them into small pieces.
Scientists claimed that these gas giants got hit by different space objects 8,000 times
more often than Earth!
Plus, thanks to gas giants, small space objects that still managed to sneak past them got
ejected out of the Solar System faster.
But without this protection, cosmic debris presented real danger!
What's more, some space objects formed ginormous clouds that tried to move closer toward the
Sun.
They looked like the icy Oort Cloud you still have in your world but much closer to the
center of the Solar System and the place where we're living now.
These clouds take ages to disperse, and they tend to send debris toward our new home.
And talking about the planet humans inhabit these days... it's Mercury!
I know, I know, Mercury in your world isn't the most hospitable place!
This planet is the closest to the Sun and the smallest in the Solar System.
With its lack of an atmosphere and extreme temperatures, it's one of the most people-unfriendly
places you can only imagine!
If our Sun hadn't turned into a red dwarf and Earth hadn't become uninhabitable, we
would have never considered Mercury as our new home.
The ice-covered polar regions of the planet are in permanent darkness.
It makes these areas incredibly cold.
And closer to the equator, daytime temperature can rise up to 800°F!
But after the sunset, it almost immediately drops to -290°F. That's what I call extreme
temperatures!
Mercury's year runs on for 88 Earth's days, while one day on this planet lasts for about
59 Earth's days.
But that's in your world, warmed by a massive super-hot star.
In my world, Mercury ended up as the only planet where humans wouldn't have frozen.
It was right inside the new "habitable zone."
If you remember, I mentioned that our Sun hadn't lost twice its mass overnight.
And although this process was fast, our scientists and engineers managed to find the way to relocate
the whole planet's population, along with most animals and plants, to Mercury.
It's rather crowded here these days, but at least we're all alive!
Don't think that our new home was overjoyed to see us.
We had tons of different, often unpredictable problems and obstacles.
Of course, the planet wasn't that mind-boggingly hot-and-cold anymore.
Its climate had become softer and milder, much more suitable for people.
Liquid water appeared, which was great news for us!
But other conditions didn't improve, not even a bit.
Mercury still doesn't have any breathable atmosphere.
That's why I can't take a relaxed stroll outside with my pooch.
We live in towns covered with protective domes and go outside only after putting on a special
suit.
I guess it looks like an astronaut's suit and is just as heavy.
And when it's particularly windy, we can't leave our towns.
If we absolutely must, we don't wander too far away and never depart without a special
rope fastened to our suits.
All because our new planet's gravity is more than twice weaker than it used to be on Earth.
And if you don't take precautions, you can be blown far away into the atmosphere.
By the way, about the atmosphere!
The gravitational pull on Mercury isn't strong enough to keep the atmosphere in place.
That's why it gets regularly blown away by solar winds.
We also have to be very careful with the Sun's radiation.
Yes, the star isn't as big or as bright as before, but it still emits enough radiation
to end your life should you step outside without special protection.
But other than that, Mercury is an impressive place to be.
It's the most cratered planet of the Solar System - the result of countless clashes with
comets and asteroids.
And the largest impact crater on the planet, called the Caloris Basin, is almost 1,000
miles across!
It's great for sightseeing!
Mercury also has wrinkles that appeared when its iron core was cooling and contracting.
These wrinkles are called Lobate Scarps and most of them are hundreds of miles long and
almost a mile high!
What a view!
Hey, if you learned something new today, then give the video a like and share it with a
friend!
And here are some other videos I think you'll enjoy.
Just click to the left or right, and stay on the Bright Side of life!