Earth, the planet we live on, is about 4.5 billion years old. At least, scientists think that’s how old it is because of some really, really ancient rocks in Australia that come from about that long ago.
Since there was no-one around 4.5 billion years ago, we don’t know for sure how the Earth and the other planets in our solar system were made. But scientists who study stars and planets millions of miles away in Space have been able to do experiments to learn about how other galaxies (enormous collections of stars and planets) are formed. And they think this must be how our planet was made, too.
So let’s find out more about how the Earth got started…!
Hair is a normal and natural part of the human body. Many people have hair on their heads and it could be yellow (blonde), red/orange, brown, black or grey/white in colour. And you may choose to wear your head hair long or short or style it in different ways.
But have you thought about the hair on other parts of your body? Like your eyebrows or nose hairs or toe hairs? My friend’s daughter has and she wants to know why do people have hairy arms and why are grown-ups hairier than children? So let’s find out…
Food is important for keeping us alive. Our bodies need nutrients from the foods we eat to keep our bodies working and healthy. And some of those nutrients give our bodies energy to keep working. Those nutrients are called ‘carbohydrates’. But what are they and how do they give us the energy we need?
Black holes are strange things in Space that scientists are still trying to understand. They were first thought of by Albert Einstein, a very famous scientist who did lots of thinking about maths and physics. Einstein’s ideas about how Space and time worked made him think that there might be ‘black holes’ in Space. But black holes weren’t actually discovered to be real until 55 years after Einstein first had the idea of them!
So what are they? Well, black holes are sort of made from old stars. So, we should start by thinking about what stars are made of, then figure out how they can turn into black holes. And then we can figure out why they are called black holes and whether they are actually black!
Have you ever noticed, when you get out of the bath or the swimming pool that the skin on your fingers and toes has gone all wrinkly? My friend’s nephew has and he wants to know why!
Pluto is a rocky, icy ball-shaped object far, far away in Space – sometimes as many as 4.7 billion miles from Earth! It’s smaller than Earth’s Moon and so far away that we didn’t know it was there until 1930.
When I was a little girl, people thought Pluto was a planet, like Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune – the other planets in our Solar System. But when scientists studied Pluto to learn more about it, they realised it isn’t quite like the other planets.
So let’s find out more about Pluto and whether it is a real planet or not…
Humans, like you and me, have existed on Earth for about 200,000 years. We are a species of animal called Homo sapiens, which means ‘wise man’. And just like all animals, we have to eat and drink in order to stay alive.
But what did the first humans eat?
It’s hard for us to know for sure exactly what humans were eating thousands of years ago because we weren’t there! But we do have some ideas based on fossilised remains that scientists have found. So let’s find out more about the early humans’ diet…