<span>Water on Mars exists today almost entirely as ice, though it also exists in small quantities as vapor in the atmosphere and occasionally as low-volume liquid brines in shallow Martian soil. The only place where water ice is visible at the surface is at the north polar ice cap.</span>
-- If you go outside at the same time every night and look at
some familiar stars, you'll see each of them them move westward
at almost exactly 1 degree per night.
-- The reason for that apparent motion is the real motion of the
Earth in its orbit around the sun, at almost exactly 1 degree in
every 24 hours.
(average during a whole year is 0.9856 degree per day.)
Population growth is the increase in the number of individuals in a population.