- a compound of the elements hydrogen and oxygen – water has the chemical formula H²O.
- ice floats – because water is the only substance less dense (heavy) as a solid than a liquid water.
- over 70% percent of the Earth’s surface is covered in water – this is why it looks blue from space.
- water is fundamental (basic) to all life – 72% of the human body is made up of water.
Human – 72% of water
- our Earth is the only planet in the Solar System to have liquid water on its surface.
Earth only has liquid water on its surface.
- Neptune has a deep ocean of ionized water beneath its atmosphere of helium and hydrogen.
- dried-up riverbeds show that Mars probably once had water on its surface – there is ice both poles and probably underground as well. (Photo – Mars Panorama by Curiosity Rover)
- a space probe found signs of frozen water on the Moon.
Lunar Frozen Water
(More information: wikipedia)