Sam: I'm Sam.
Neil: And I'm Neil.
The 20th of July 1969 was a big day in history.
Do you know why, Sam?
Sam: Wasn't that when Neil Armstrong first set foot on the moon?
Neil: Right.
But it's often forgotten that some of the most dramatic photographs taken
on the Apollo space mission weren't of the moon at all – they were of Earth.
It wasn't until we went to the moon
that we really saw the size of Earth's oceans and named ourselves, the Blue Planet.
Sam: Despite most of our planet being covered by water,
the ocean remains of place of unexplored mystery,
of sea monsters like Moby Dick, and the Kraken.
In this programme, we'll be diving into the deep seas,
seeing some of its strange sights,
and as usual, learning some related vocabulary too.
Neil: But before that I have a question for you, Sam.
You were right when you said that most of the Earth is covered by water.
But do you know exactly how much of the Earth's surface is ocean? Is it:
a) 50 percent?