五十四年了，人类又回到了月亮

NASA's Artemis 2 mission has successfully come home.

The four astronauts' spacecraft landed in the Pacific Ocean at 8:07 PM tonight.

The landing spot was near the coast of San Diego, California.

This is a historic moment.

Why do we say so?

Because this is the first time since 1972.

That humans have really flown as far as the moon.

The last mission like this was Apollo 17.

That was already fifty-four years ago.

Fifty-four years.

Think about how big that number is.

In these fifty-four years.

Humans have gone to space many times.

But most of them were in "low Earth orbit."

Low Earth orbit is a few hundred kilometers from Earth.

This sounds far.

But compared to the moon.

It's just next to Earth.

How far is the moon from Earth?

The moon is about 380,000 kilometers from Earth.

Yes, 380,000.

So from the International Space Station to the moon.

Is a thousand times the distance from the station to Earth.

Artemis 2 didn't land on the moon.

They just flew around the moon once.

But this is already remarkable.

Because no one had done this since 1972.

A full fifty-four years.

Now let's talk about who these four people are.

The commander is Reid Wiseman.

The other three are Victor Glover, Christina Koch, and Jeremy Hansen.

The first three are Americans.

Jeremy Hansen is Canadian.

This is the first time in history that a non-American astronaut has flown this far to the moon.

The Canadians are very proud of this.

Their spacecraft is called Orion.

This particular spacecraft was also given a name — Integrity.

Integrity in English means honesty and uprightness.

The entire mission lasted ten days.

What did they do in those ten days?

They tested all the spacecraft's systems.

They took many photos of the moon and Earth.

They flew around the moon.

They experienced 48 hours of "free flight."

Meaning a state of not being bound by the moon's gravity.

Then they started flying back to Earth.

The trip home is the most dangerous part.

Why?

Because the spacecraft enters the atmosphere at very high speed.

The top speed is close to 40,000 kilometers per hour.

This is almost as fast as Apollo's top record.

At this speed, entering the atmosphere.

Friction generates huge amounts of heat.

How hot?

The outside of the spacecraft reached 5,000 degrees at its hottest.

5,000 degrees Fahrenheit is about 2,700 degrees Celsius.

This temperature can directly melt most metals.

But the astronauts inside must stay alive.

So the outside of the spacecraft has a special material.

This material is specifically designed to block this heat.

This technology is called a heat shield.

During the entire reentry process.

The astronauts endured about four G's of gravity.

Four G's means you feel your body weight has become four times normal.

There was also a communications blackout of about six minutes in this process.

Because during reentry, plasma forms around the spacecraft.

Plasma blocks radio signals.

So during those six minutes.

The ground had no idea about the astronauts' condition.

Those six minutes were very nerve-wracking for everyone.

Then the signal came back.

The parachutes opened.

The spacecraft slowly landed in the Pacific Ocean.

Mission Control said it was a "perfect precision splashdown."

All four astronauts were fine.

When they came out of the spacecraft, they walked on their own.

The doctor said they "feel great."

U.S. President Trump watched the live broadcast.

He congratulated the astronauts.

And said the next goal is Mars.

Now let's talk about what happens next.

Artemis 2 just flew past the moon.

Didn't land.

The real landing is the Artemis 3 mission.

Artemis 3 will let humans step on the lunar surface again.

The last time someone walked on the moon was 1972.

Fifty-four years have passed since then.

When will Artemis 3 launch?

No date has been set yet.

But it should be within the next few years.

When that day comes.

We will see an astronaut walk on the lunar surface again.

And this time.

There will be the first woman and the first non-white astronaut to land on the moon.

These are all things NASA has promised to do.

But why return to the moon?

Nobody went for fifty-four years.

Why go again now?

There are several answers.

The first is Mars.

Humanity's long-term goal is to go to Mars.

But Mars is very far.

From Earth to Mars takes six to nine months to fly.

Before going, we must first learn how to live on the moon.

The moon is like a practice place.

The second is resources.

The moon's south pole has water ice.

Water can become oxygen for people to breathe.

It can also become rocket fuel.

So the moon could become a gas station for space exploration.

The third is science.

We know very little about the far side of the moon.

The moon's south pole is even more of an unknown.

There's too much worth exploring in these places.

So Artemis 2 is not an end.

It's a beginning.

The beginning of a new space era.

Tonight, four astronauts came home safely.

But humanity's footsteps haven't stopped.

Next time we will go even further.