Most people are used to having four seasons- Summer, Autumn, Winter and Spring. However, some indigenous calendars divide the year up differently based on subtle changes in the natural environment. For example, the Yarwuru tribe has seven seasons, while the Miriwoong tribe only has three.
Aborigines observed the relationship between changes in the astronomy and corresponding changes in flora and fauna. Stories about the rising and setting stars and constellations, as well as movements of the sun, moon and planets were passed on to teach Aboriginal Australians when it was time to move on and find a new source of food.
1. Go the the Australian Bureau of Meteorology Indigenous Weather page and research an Aboriginal tribe.
2. Write a report about the different seasons within this tribe, and what changes happen in each of these seasons.
1. What other countries/ cultures use different seasons other than Summer, Autumn, Winter and Spring? What are they?
2. Why might countries experience different seasons?
There is evidence Aboriginal Australians may actually have been some of the first astronomers. For example, according to oral tradition, the rock engravings by the Nganguraku people at Ngaut Ngaut (shown at the top of the page) represent lunar cycles. Lunar cycles influences the tides. Tides are caused by the gravitational pull of the sun and moon, which can be used to tell the time.
Indigenous people living on the coast often refer to themselves as Saltwater people and their lives revolve around the sea and the tides. Saltwater people often express their concepts of time based on natural processes, such as tides, seasonal winds and currents.
Tide cycles are very predictable. For example, in locations where there are two high tides and two low tides every day, the tide that occurs on a full moon or new moon is called the spring tide. The spring tide always occurs around 3.00 am (low), 9.00 am (high), 3.00 pm (low) and 9.00 pm (high). In most places high tide is six hours after low tide, and you can use this even if you can't see the moon directly.
At full moon a normal sundial can be used as a moon dial, just like a sun dial during the day. If you can see the moon, you can watch its progress across the sky and estimate the time in the same way that you would with the sun.
Why don't you try looking at the moon and see if you can estimate the time based on its position? It may take you a bit of practice.
Scientists have also started to use this ancient wisdom and build tidal clocks. Examples include the Aluna, the world's first tidal powered Moon Clock, and the Portsmouth Tide Clock.
1. Research a tidal-powered clock. How do they work?
2. Organise a school excursion to the beach. Use this Junior Rangers activity to learn more about tide charts and the affect of the sun and moon on tides.