- And now, here's my friend, astronomer Amy Mainzer.

- Thanks, Jet.

One of the things you often notice about the night sky when it's clear is our amazing, beautiful Moon.

You can see the Moon in the night time and sometimes even during the day.

Sometimes the Moon is hard to spot during the daytime.

But at night, it can be very bright and easy to see.

Earth's Moon can look so bright because we're seeing light from the Sun bounce off its surface.

When we look at it close up, we can see that it's actually made of grey rocks.

We know this because we've been to the Moon.

Astronauts have walked on it and even driven on it.

And we've sent dozens of robots to explore.

The astronauts look like they're bouncing on the Moon because the pull of the Moon's gravity is much weaker than the Earth's.

And notice, the astronauts are wearing big, bulky spacesuits.

That's because the Moon doesn't have an atmosphere like the Earth's.

There's no breathable air.

So astronauts have to bring their own.

Space suits also keep astronauts at a comfortable temperature.

That's because the Moon can be either really hot or really cold.

On Earth, the air acts like a blanket, keeping the temperature just right.

But the Moon doesn't have that thick blanket of air, so there's really nothing to regulate the temperature.

So the next time you're thinking about visiting the Moon, just remember... Bring a space suit.

- Thanks, Amy!

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