Observations provide a huge amount of evidence that the Universe is OLD.
Here on Earth we can see changes going on. If we believe our own eyes then we know that in some places the changes must have been going on for millions of years. There are similar observations about deeper layers of rock. Other planets and moons in the Solar System have evidence in their surfaces to show that processes there have been happening for a long time. And when we look at distant galaxies we can work out the light from them has taken as much as 13 BILLION YEARS to reach us.
The outer layers of the Earth move. New York and London are moving apart as quickly as your fingernails grow. Sometimes there are sudden jolts - earthquakes. Mountains rise up. In many places in the world the movements are clear enough to be measured. Layers of rock build up and buckle and then wind and water wear them away. We can only explain the observations if these process have been happening for a very long time.
Stars change, too. We can only explain observations of stars and galaxies if the changes have been happening for many billions of years.
Go to the University of Waikato's page on Geological Time to answer these questions.
- How can scientists compare the ages of different rocks in the same place?
- How can they compare the ages of rocks from different continents?
- How does radioactivity help?
Find out about:
The age of the Earth compared with the age of fossil dinosaurs.
The age of the Earth compared with the age of the Universe.
Observation and faith