Saturn's moon Titan has plenty of evidence of organic (life) chemicals in its atmosphere.
A comet’s tail is made as it nears the Sun and begins to melt.
A vast plume of gas millions of kilometers across is blown out behind by the solar wind.
The tail is what you see, shining as the sunlight catches it.
The Drake Equation was proposed by astronomer Frank Drake to work out how many civilizations there could be in our galaxy - and the figure is in millions.
The Sun travels around the galaxy once every 200 million years – a journey of 100,000 light years.
There may be a huge black hole in the very middle of the most of the galaxies.
The very farthest galaxies are spreading away from us at more than 90% of the speed of light.
The Universe was once thought to be everything that could ever exist, but recent theories about inflation (e.g. Big Bang) suggest our universe may be just one of countless bubbles of space time.
The Universe may have neither a center nor an edge, because according to Einstein’s theory of relativity, gravity bends all of space time around into an endless curve.
Matter spiraling into a black hole is torn apart and glows so brightly that it creates the brightest objects in the Universe – quasars.
The Milky Way galaxy is whirling rapidly, spinning our sun and all its other stars at around 100 million km per hour.