Water appeared on Earth longer ago than scientists first thought

Most of the surface of Earth is made up of water but when did this important resource first appear in our solar system?

Over 1,000 quintillion litres of water exist on Earth, mostly making up the huge oceans that cover the surface, but when did water first appear in our universe?

Well a new study suggests this important resource formed 200-400 million years after the Big Bang, when the universe formed, which is thought to have happened 14 billion years ago.

This is a lot earlier than previously thought.

Dr Daniel Whalen from Portsmouth University and co-authors published their findings in the journal Nature Astronomy.

Using computer simulations the researchers created the explosions of two stars.

In the virtual supernovae - the name for when a star explodes - the temperatures were found to be high enough to turn the former star gases into Oxygen.

This gas then cooled and mixed with another gas hydrogen which formed water.

Scientists say their discovery shows that habitable worlds could have formed billions of years earlier than previously thought.

They also say the simulations show that water was a key part of the first galaxies and that the amount formed then is only a tenth of what is seen in the galaxy today.