The first images, from ten thousand kilometres away, brought to a halt the activities of all mankind.

After all, it would be hard for us to check what your boys were up to, from a billion kilometres away.

It is over 30 kilometres long and ranges from three to four kilometres wide.

It is estimated that 65% of the patients served come from 15 kilometres of the hospital.

From six kilometres to the summit, it averages 13.1%.

The resulting scar is very noticeable from many kilometres distant.

It is 17 kilometres from east to west across this triangle and some 16 kilometres north to south.

With the help of a good wind, they can smell dead animals from 4-9.5 kilometres (2.5-6 mi) away.

An adult lion's roar can be heard from up to 8 kilometres away.

The human eye can see a candle flame from 50 kilometres on a clear, dark night.