Hey Space Nerds, Aaron Scott here.

So NASA's Artemis Moon mission was supposed to launch Monday.

The rocket didn't go because of a problem with one of its engines,

but NASA hopes to get it fixed soon.

And when it launches, it'll be a giant step towards sending humans back to the moon.

But one of the things we want to know is what are the scientific questions they're going to answer by going there?

It's a question that was first planted in our minds by the scientist Hal Walker,

who is involved in the first lunar landing half a century ago.

He was tasked with shooting lasers at the moon to find out just how far away it is.

His story today, enjoy.

You're listening to Shortwave from NPR.

For the eyes of the world, now look into space to the moon and to the planets beyond.

In the early 60s during the space race, President John F. Kennedy set a national goal.

We have vowed that we shall not see space,

filled with weapons of mass destruction, but with instruments of knowledge, and understanding.

The promise was simple.

Send a crew of U.S. astronauts to the moon, land, and return to Earth.

So on July 20, 1969, much of the world stood still, as NASA's Apollo 11 crew fulfilled this national vow.

The quality base here, the eagle has landed.

Becoming the first group of astronauts from any nation to land on the moon.

It's one small step for man, one giant leap for man.

And in order for us to see it, the crew actually had to set up a television camera

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