Indigenous astronomy and seasonal calendars

Aboriginal and Torres Strait Islander people have an understanding of how the stars and constellations are connected to environmental phenomena on Earth.

They developed complex seasonal calendars that incorporate detailed knowledge of the positions of stars and constellations with corresponding terrestrial events, such as changing weather patterns, animal behaviour, and the availability of plants and medicines. This knowledge was used to sustainably alter the environment to enhance the availability of food and medicines.

Astronomy, seasons, and ecology

For every region across Australia, Aboriginal and Torres Strait Islander peoples closely observe the life cycles of the plants, animals, and insects, how they tie with the seasons, and how these cycles repeat year after year. This knowledge has been refined over tens of thousands of years, adapting to various environmental changes that have occured over that time. They relate the flowering and fruiting times of important food and medicinal plants, the timing of animal breeding and insect life cycles, the movement of birds to inland rivers and waterways, and annual whale migrations along the coast. This information was recorded and encoded into oral history, song, dance¹, and ceremony, ensuring it could be accurately passed and maintained.²

Indigenous Knowledge is developed in situ, meaning the body of knowledge generally relates to the environment and region in which it was developed. Today, there are increasing efforts to record and preserve Indigenous Ecological Knowledge in the form of informative regional resource calendars (Fig. 1), each specific to its relevant region.³ Each chart contains and conveys several layers of interrelated information on season names and times of year, the seasonal quality (wet/dry, hot/cold, predominant wind direction, etc.) what animal, plant or insect is abundant for each season, and other relationships. These are generally marked by the appearance of important seasonal stars at dusk and/or dawn that herald these changes.

Seasons and seasonal stars

In many Aboriginal and Torres Strait Islander traditions, each season was heralded by the appearance of an important indicator star, or sometimes a group of stars (asterisms). Around the Adelaide Plains, South Australia, for example, the Kaurna people recognise four distinct seasons similar to those found in European traditions. Each of the four seasons, Kudilla (Winter), Wilto (Spring), Wolta (Summer) and Parna (Autumn) was accompanied by the appearance of one or more stars in the sky at dusk.⁴

Fig 1: A seasonal resource calendar for the Walmajarri people of The Kimberley region of Western Australia. Image: CSIRO⁵

Studies show the connection between the annual appearance of constellations in the night sky and the cycles of their associated terrestrial counterparts.⁶ In particular, the star cluster known as the Pleiades (aka Seven Sisters) is linked to many important traditions across Australia. Along the east coast, they are linked to whale migrations. Their first predawn appearance (heliacal rise) in early June signifies the start of winter and the beginning of the migration of whales from their summer feeding grounds in Antarctica to their winter breeding grounds in Northern NSW and Southern Qld. The acronychal setting (last appearance in the West before setting at dawn) of the Pleiades in October-November coincides with the southerly migration back to Antarctica, with young calves in tow.

In the Central Desert, the heliacal rise of the Pleiades signifies the ‘official’ start of winter and the peak in the Dingo breeding cycle. Dingoes are important, both as a source of warmth against the cold winter nights, and as a source of food when other foods were scarce during droughts.⁷ Seeing the Pleiades in the dawn sky told them it was time to look for dingo pups. The Pleiades are also linked to many other plants and animals through interrelated traditions and Songlines, such as bush tomatoes (Kutjera), honey ants (Tjala) and Thorny Devils (Mingari).⁸

Perhaps the best known night sky calendrical indicator is the Emu in the Sky, or Celestial Emu.⁹ The Celestial Emu is found in the dark dust lanes of the Milky Way between the Southern Cross (Head), Scorpius-Sagittarius (body) and Ophiuchus-Aquila (feet) (Fig. 2). The seasonal calendar relates to the changing orientation of the Celestial Emu (Gugurmin in Wiradjuri, Gawarrgrgy/Gawarghoo in Kamilaroi/Euahlayi) through the year, and its links to the breeding cycle of the terrestrial emu (Dinawan). Its first appearance in the dusk sky in April-May (Fig. 3A) signifies the start of the Emu breeding cycle, when the females chase the males before mating. When the Celestial Emu is horizontal in the sky in June, this is the time when terrestrial emus are nesting and laying eggs. Students will examine this in more depth for the Year 8 Health module.

Fig. 2: The changing perspective of the Celestial Emu through the year, each connected to a particular aspect of an overall dreaming narrative connected to the lifecycle of the terrestrial emu and its link to ceremony. (A) April-May, when the female terrestrial emu are chasing males and pairing up. (B) June-July, when the Male emus are sitting on eggs. Image: Ghillar Michael Anderson and Robert Fuller (Journal of Astronomical History and Heritage), used with permission.

Classroom activity - Humanities and Social Sciences (HASS) Year 5

In this classroom activity students will create a seasonal resource calendar based on observing and researching the life cycles of local flora and fauna, and then relate these cycles to the annual appearance of seasonal stars.

Curriculum connections

This resource addresses the following content description from the Australian Curriculum:

• Types of resources (natural, human, capital) and the ways societies use them to satisfy the needs and wants of present and future generations (ACHASSK120)

This resource addresses the following excerpts from the achievement standard for Year 5 in Humanities and Social Sciences (HASS):

• identify and describe the interconnections between people and the human and environmental characteristics of places, and between components of environments
• identify the effects of these interconnections on the characteristics of places and environments
• recognise that choices need to be made when allocating resources
• develop questions for an investigation
• locate and collect data and information from a range of sources to answer inquiry questions
• interpret data to identify and describe distributions, simple patterns and trends, and to infer relationships, and suggest conclusions based on evidence

Activity – Examining seasonal calendars

Suggested timing: 30-45 minute activity and discussion

Required resources: Computer, internet access, printed or online copy CSIRO Indigenous seasons calendars¹⁰

1. Go to the CSIRO Indigenous Seasons Calendars website and view the different calendars available online.
2. Students should compare calendars from two or more regions and discuss the below questions as a class:
   1. What do these calendars focus on in relation to community needs? Food, water, weather?
   2. How do these calendars help the people live sustainably?
   3. How are these resources linked to Aboriginal and Torres Strait Islander Peoples' connection to the land?
   4. Do these calendars feature an astronomical component? If not, why?
3. Students can then examine two astronomical objects and discuss where they could be placed within the seasonal calendar:
   1. The first is the Coalsack nebula, which is a dark space in the Milky Way next to the Southern Cross (they can read about it online). When is it visible in the dawn sky from Bathurst and Melville Islands (Tiwi country)? (They can use Stellarium to examine this).
      1. Teacher note: it is only visible during the wet season from November to March. Therefore, that would be a useful indicator of that season, which is noted in Tiwi traditions.¹¹ In Tiwi traditions, a group of star-women make their camp within the Coalsack. Since it is only visible during the wet season, they do not have any camp fires. It’s also the reason the Coalsack doesn’t appear to have any stars in it.
   2. The Tiwi see the stars of Orion (Daiimini) as a pack of dingoes who are chasing a mob of wallabies in the Pleiades (Karaka). When are these stars first visible in the dawn sky? What season does this link to? How might wallabies and dingoes link to this season?
      1. Teacher note: the Pleiades rise at dawn in June. Pure dingoes generally breed from March to June, meaning the first litters are birthing in May and June, since the gestation period is about 9 weeks. Wallaby’s breed from January to February, and borth after 28 days. They stay in the pouch for another two months, meaning they start roaming about around May and June, the time dingoes are pursuing them for food.

Teachers can discuss with the students the needs of the people reflected in the calendar, and how the stars can inform seasonal change related to animal behaviour.