Some cool facts about the Universe

• When you look into the night sky, you are looking back in time

• Many of the atoms you're made of, from the calcium in your bones to the iron in your blood, were brewed up in the heart of an exploding star billions of years ago.

• And back in the days before digital television, if you tuned your TV between stations, a small percentage of the static you would see would actually be the afterglow of the Big Bang.

• Outer space is silent. Eerily silent. That's because sound waves need some sort of medium to travel through. And space is a vacuum. A dark, silent vacuum.

• The sun makes up 99.86% of the mass of the solar system. It's so big that you could squeeze 1.3 million Earths inside of it.

• There might be as many as three sextillion stars in the universe. That's 3 followed by 23 zeros, or 300,000,000,000,000,000,000,000. That's more than all of the grains of sand on Earth.

• Ordinary, observable matter (like stars and planets) makes up a measly 5% of the universe. The other 95% universe is made up of invisible dark energy (68%) and dark matter (27%). That means there's 95% of the universe that we don't know about yet.
• It takes 225 million years for our Sun to travel round the galaxy
• Our solar system’s biggest mountain is on Mars
• The human brain is the most complex object in the known universe
• We are all made of stardust