The ancients and meteors

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There are all sorts of cyc­lical events that ancient peoples are thought to be inter­ested in, sol­stices, lunar cycles and eclipses. What rarely seems to get atten­tion are met­eor showers. It might seem odd, they’re annual, hap­pen­ing at the same point in the Earth’s orbit. They can also be spec­tac­u­lar. So why don’t they get much atten­tion from archae­oastro­nomers? There are prob­ably a couple of reasons.

Meteor and Pleiades

Meteor and Pleiades. Photo: Luis Argerich / Flickr.

One is that there’s not a lot of clear his­tor­ical evid­ence that met­eor showers were pre­dict­able in the ancient world. The ancient cer­tainly saw met­eor showers, one of my favour­ites is Plutarch writ­ing on pleasure:

…[P]leasures, like gales of soft wind, move sim­per­ing, one towards one extreme of the body and another towards another, and then go off in a vapor. Nor are they of any long dur­ance, but, as so many glan­cing met­eors, they are no sooner kindled in the body than they are quenched by it.

It’s clear that who­ever wrote that must have been famil­iar with fleet­ing met­eors showers. There’s also evid­ence of peri­odic obser­va­tions for met­eors, again from Plutarch, but these weren’t annual events. From his bio­graphy of Agis, a king of Sparta:

Every ninth year the eph­ors select a clear and moon­less night, and in silent ses­sion watch the face of the heav­ens. If, then, a star shoots across the sky, they decide that their kings have trans­gressed in their deal­ings with the gods, and sus­pend them from their office, until an oracle from Delphi or Olympia comes to the suc­cour of the kings thus found guilty.

Plutarch — Agis 11.3

Every ninth year in this case means every eighth, because of inclus­ive count­ing. It seems that while met­eors were well-known in the ancient world they were unex­pec­ted. If you count your cal­en­dar against the moon, as most ancient cul­tures did, then events like sol­stices hap­pen on dif­fer­ent days of the year. So too would met­eor showers. Along with the vagar­ies of weather and they tend to be vari­able in strength any­way, it might be less of a sur­prise that they weren’t pre­dicted and planned around.

It’s not just his­tor­ical evid­ence we could look for though. Continue read­ing

Where can you find out more about the UNESCO Astronomy World Heritage Inititative?

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For any­one search­ing for my name today, here’s the inform­a­tion you’re after.

The bit I’m work­ing with is the Portal to the Heritage of Astronomy. This is the part where all the pub­lic inform­a­tion is.

There are pages about the ini­ti­at­ive at UNESCO and the IAU.

It’s excel­lent report­ing by Andy Carling, so if I’ve said any­thing incor­rect or muddled then it’s def­in­itely me who got it wrong, not some com­mu­nic­a­tion mix-up.

The earliest astronomers?

Reaching for the stars in Lascaux Cave
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This post was chosen as an Editor's Selection for ResearchBlogging.orgThe short ver­sion of this post is that Astronomy in the Upper Palaeolithic? by Hayden & Villeneuve is a great paper. If you’re inter­ested in astro­nomy in hunter-gatherer soci­et­ies you should read it. I’m going to dis­agree with some parts of the paper below, but if Hayden & Villeneuve are wrong about some things, then it’s for inter­est­ing reas­ons. And it’s by no means cer­tain that I’m right to dis­agree about the things that I do.

Reaching for the stars in Lascaux Cave

Reaching for the stars in Lascaux Cave. Photo (cc) tourisme_vezere.

The archae­ology of astro­nomy is con­ten­tious at the best of times, but the Palaeolithic is a par­tic­u­larly dif­fi­cult period to study, because the remains are so frag­ment­ary and few in num­ber. So to put this in con­text we need to know when the Upper Palaeolithic is.

You’re prob­ably famil­iar with the Three Age System, Stone, Bronze and Iron Ages. In this sys­tem in Europe the Stone Age ends roughly between 4000 and 2500 BCE depend­ing on where you are and exactly where you want to draw the line. Everything before this is a long time period so you can split it up fur­ther. The Neolithic is a period when people settle down and become farm­ers, it starts between 8000 and 4000 BCE in Europe depend­ing on where you are. The south-east of Europe adopts farm­ing much sooner than the people in the north-west. The Palaeolithic, if you ignore all sorts of sub­tleties is the period before that. To nar­row down things fur­ther the Palaeolithic is sub-divided into three sec­tions, Lower, Middle and Upper. Again, roughly speak­ing, the Lower Palaeolithic is the time of early humans, the Middle is the time of Neanderthals roughly 300,000 BCE to 35,000 BCE, and the Upper Palaeolithic is the period after that with Homo Sapiens.

This gives the astro­nom­ical read­ers a rough idea of when we’re talk­ing about. Archaeological read­ers could very eas­ily pick holes in more or less everything I’ve said about the dates. One import­ant reason we’ll get to later is that when we use terms like Bronze Age or Palaeolithic, we’re not dir­ectly talk­ing about a spe­cific time, we’re talk­ing about the tech­no­logy we find that’s asso­ci­ated with a spe­cific time. So some ‘peri­ods’ make no sense out­side of Europe. If you live some­where where Obsidian was much easier to get than Bronze, then it’s pos­sible local people never bothered with a Bronze Age.

Hayden & Villeneuve real­ise that evid­ence from the Upper Palaeolithic is scant, but they also recog­nise that the Upper Palaeolithic is not just a time, but it’s tied to a place. What they’re inter­ested in is whether or not eth­no­graph­ies of mod­ern hunter-gatherer soci­et­ies can give us inform­a­tion about pos­sible uses for astro­nomy. You can’t simply say that mod­ern hunter-gatherers from now were exactly like hunter-gatherers twenty thou­sand years ago, but you can see if tack­ling astro­nom­ical prob­lems pro­duces debris sim­ilar to what archae­olo­gists find. You can also see if there are com­mon fea­tures in astro­nomy around the world from hunter-gatherers. If you can see hunter-gatherer astro­nomy in action then you have clues why hunter-gatherers used astro­nomy in the past and that can pro­duce work a lot more inter­est­ing than “there’s marks on this bone, people could be count­ing moon phases.“
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Time as an anachronism

Surreal time photo
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I’m writ­ing up a paper, and because it’s one I haven’t actu­ally fin­ished yet I quite like it. It ties up some loose ends with pro­ject. It also adds some­thing new to ancient polit­ics without hav­ing to con­tra­dict a lot of people. It’s been going quite well so I’ve star­ted writ­ing up the Introduction and I must have been slightly on auto­matic because I’ve run smack into the ques­tion “What is Time?” A lot of people much more intel­li­gent than me have been banging their heads against this prob­lem for mil­len­nia, so I’ll be doing well to solve it in a couple of para­graphs. I think for my work I’ve man­aged to tighten the prob­lem into two smal­ler ques­tions. Is the mod­ern exper­i­ence of time as a largely object­ive pas­sage of dur­a­tion ana­chron­istic when you look at the ancient world?

Plato in the Timaeus 38c says:

Wherefore, as a con­sequence of this reas­on­ing and design on the part of God, with a view to the gen­er­a­tion of Time, the sun and moon and five other stars, which bear the appel­la­tion of “plan­ets,” came into exist­ence for the determ­in­ing and pre­serving of the num­bers of Time.
trans. Perseus Project CC licenced BY-SA



This means that Plato saw the plan­ets as cre­at­ing time. This is the inverse of how we think of time, because we think time would exist any­way and that time is some­thing that plan­ets move in. So do we need a rad­ic­ally dif­fer­ent men­tal model for how ancient people though about time? I’m not sure. For a counter-argument here’s a bit of Clouds by Aristphanes. Strepsiades is bothered about his debts and how he can­not afford to pay them back. He goes to Socrates, to teach him how to think:

Socrates
Do you, your­self, first find out and state what you wish.

Strepsiades
You have heard a thou­sand times what I wish. About the interest; so that I may pay no one.

Soc.
Come then, wrap your­self up, and hav­ing given your mind play with sub­tilty, revolve your affairs by little and little, rightly dis­tin­guish­ing and examining.

Strep.
Ah me, unhappy man!

Soc.
Keep quiet; and if you be puzzled in any one of your con­cep­tions, leave it and go; and then set your mind in motion again, and lock it up.

Strep.
(in great glee). O dearest little Socrates!

Soc.
What, old man?

Strep.
I have got a device for cheat­ing them of the interest.

Soc.
Exhibit it.

Strep.
Now tell me this, pray; if I were to pur­chase a Thessalian witch, and draw down the moon by night, and then shut it up, as if it were a mir­ror, in a round crest-case, and then care­fully keep it–

Soc.
What good, pray, would this do you?

Strep.
What? If the moon were to rise no longer any­where, I should not pay the interest.

Soc.
Why so, pray?

Strep.
Because the money is lent out by the month.

trans. Perseus Project CC licenced BY-SA



In ancient Greece a month was a lun­ation, the period of time from one New Moon to the next. By remov­ing the moon Strepsiades removes months. This seems to back up Plato’s ideas about plan­ets gen­er­at­ing time (the Sun and Moon were πλάνητες ἀστέρες, plan­etes asters or wan­der­ing stars, in the ancient world). But the joke only works if the solu­tion is non­sense. Pulling down the moon is a daft idea, but is the idea that months would cease to have mean­ing too? The Romans lived per­fectly well without lunar months.

Herodotus (II.4.1), writ­ing around the same period, was clear that lunar months weren’t good ways to track time.

But as to human affairs, this was the account in which they all agreed: the Egyptians, they said, were the first men who reckoned by years and made the year con­sist of twelve divi­sions of the sea­sons. They dis­covered this from the stars (so they said). And their reck­on­ing is, to my mind, a juster one than that of the Greeks; for the Greeks add an inter­cal­ary month every other year, so that the sea­sons agree; but the Egyptians, reck­on­ing thirty days to each of the twelve months, add five days in every year over and above the total, and thus the com­pleted circle of sea­sons is made to agree with the cal­en­dar.
trans. Perseus Project CC licenced BY-SA



From this it looks like time is quant­at­ive. For example if today is Tuesday, then even if it feels like a Monday it can’t be Monday because Monday + 1 day = Tuesday. I think this can­not be purely the case for ancient Greece though.

For example McCluskey (2000:18) and Pritchett (2001) both note that the cal­en­dar can pause or skip days. The same is true for months. To keep the Greek cal­en­dar in line with the sea­sons they didn’t insert an extra day every so often, they inser­ted a whole month as Herodotus says above. You end up try­ing to match months against sea­sons and sea­sons have qual­it­ies. These days in the UK we say Spring starts on March 21. In real­ity Spring starts when the weather improves. Spring can come earlier or later. If you’re in a soci­ety that doesn’t recog­nise a fixed num­ber of days in a solar year, like ancient Greece, then the qual­ity of the days become import­ant. The cal­en­dar is used to reg­u­late reli­gious acts and if a cer­tain fest­ival is sup­posed to be at the start of Spring and the flowers or anim­als asso­ci­ated with the fest­ival are not yet out then it’s not the right day and the cal­en­dar needs to be corrected.

While the Greeks shared com­mon reli­gious beliefs, on the details they were fiercely inde­pend­ent. In this period tak­ing part in a reli­gious event was a polit­ical state­ment about belong­ing to a polis, a city-state. Non-citizens did not have the right to par­ti­cip­ate in the events in the same way as a cit­izen. So if reli­gion was used to define us from them and the cal­en­dar was a reli­gious tool, then a neut­ral object­ive count is not good enough. They wanted to be able to have their own dis­tinct­ive calendrical cycle. I think that’ll be some­thing I need to cla­rify. It’s not that the Greeks couldn’t make an accur­ate cal­en­dar. It’s that, for the job they wanted it to do, a less pre­cise cal­en­dar was bet­ter.

Where does that leave Herodotus? Clearly the Greeks weren’t stu­pid and if Herodotus knew that a three-hundred and sixty-five day cycle made sense, you can be sure many in his audi­ence did too. But Herodotus had his own axe to grind.

Herodotus was writ­ing towards the end of the fifth cen­tury BC. Athens and Sparta had been rivals for dec­ades con­test­ing the power vacuum cre­ated by the defeat of Persia. Herodotus wrote about the Persian War, not his own time. His aim was to recall a Panhellenic glory shared by all Greeks. A three-hundred and sixty-five day cycle wouldn’t inher­ently dis­solve all intra-Hellenic dif­fer­ences but it would social bonds between the Greeks. I don’t think it was a con­scious polit­ical state­ment, but I think the com­ment on the Egyptian cal­en­dar reflec­ted the Panhellenic ideals you find else­where in the History.

Every so often someone will tell me ‘there’s no such thing as ancient sci­ence’. Usually when I’m asso­ci­ated with the Centre for Interdisciplinary Science. They’re right. Science is a mod­ern social con­struct that doesn’t fit neatly on to the ancient world. On the other hand it is a con­veni­ent label for attempts to pro­duce gen­er­al­ised explan­a­tions and prac­tices, without imme­di­ate recourse to super­nat­ural beings, estab­lished with at least the attempt of a pre­tence at rational jus­ti­fic­a­tion. And it’s good enough for the much cleverer people who write the vari­ous volumes in Routledge’s Sciences of Antiquity series. But I agree with the idea that if you’re not aware of the dif­fer­ence, it’s some­thing that will come back to bite you. In the same way, I’m not sure that the way we think about Time can applied back to the past. The dif­fi­culty is that it’s such a slip­pery sub­ject I don’t know if I always have a grasp about how I think about Time in the present.

Bibliography

McCluskey, S.C., 2000. The Inconstant Moon: Lunar Astronomies in Different Cultures. Archaeoastronomy, 15, p.14–31.

Pritchett, W.K., 2001. Athenian Calendars and Ekklesias, J C Gieben.

A medieval chapel pierced by an ancient light?

La Hougue Bie by Sam K
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I learned some­thing new read­ing Mark Patton’s post on an equi­noc­tial align­ment at La Hougue Bie on Jersey. I knew the mega­lithic tomb at La Hougue Bie was equi­noc­tially aligned. It was also no sur­prise there was a reli­gious build­ing there, because it’s com­mon for Christian sites to be built over pagan sites. Sometimes there are good archi­tec­tural reas­ons for build­ing over sites. Sometimes it’s a stamp of author­ity say­ing that Christianity was in con­trol. What I hadn’t real­ised is that there’s an equi­noc­tial align­ment in the 12th cen­tury chapel of Notre Dame de la Clarté (Our Lady of the Light) added by Richard Mabon in the 16th cen­tury. He built a win­dow to light the Oratory. Looking at the photo you might won­der how I missed that, but the pho­tos I’d seen on La Hougue Bie were of La Hougue Bie, by pre­his­tor­i­ans with little inter­est­ing the later mater­ial over the top of the tomb.

The ques­tion is, is this shared align­ment inten­tional or a coin­cid­ence? My first reac­tion is that it’s a coin­cid­ence — but if it is then it could be a lot more inter­est­ing than if Mabon had been aware of the tomb beneath the chapel.
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There are more things in heaven and earth, cobber, than are dreamt of in your philosophy

Astronomically inspired indigenous art at the Ilgarijiri exhibition on display in Geraldton. Photo (cc) AstroMeg.
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This post was chosen as an Editor's Selection for ResearchBlogging.org Studying astro­nomy in cul­ture should be simple. There’s only so much that is vis­ible by the naked eye, and it fol­lows pre­dict­able pat­terns. Modern astro­nomy means that we can recon­struct what was vis­ible any­where in the world in human his­tory, within cer­tain bound­ar­ies for errors. If we know what hap­pens when, then study­ing a cul­ture should just be a case of tak­ing a shop­ping list of astro­nom­ical phe­nom­ena and see­ing what a cul­ture does with them. And some bad his­tor­ies of astro­nomy read like the author is award­ing marks to cul­tures for astro­nom­ical achievements.

There’s vari­ous things that don’t work with that plan, but the biggest is that you sup­posedly are examin­ing cul­ture and are fit­ting a study to a very spe­cific view of astro­nomy, a mod­ern west­ern view. It’s awk­ward because we live in a cul­ture where a mod­ern Platonic view of sci­ence is rarely chal­lenged. There’s a good reason for that. Our view of sci­ence makes sense within our cul­ture. But if we don’t acknow­ledge that sci­ence is a social con­struct then we don’t fully under­stand other cul­tures. Reality is the same for all of us, but not our way of mak­ing sense of it. An Overview of Australian Aboriginal Astronomy by Philip A. Clarke in Archaeoastronomy is a good paper that helps show the dif­fer­ence between under­stand­ing the use of astro­nomy in a cul­ture and com­par­ing an indi­gen­ous astro­nomy with ours to see how much they got right.

The paper starts at the very best place to start, as after a brief intro­duc­tion it con­siders the sources of the data. It’s a key point because if the source data is full of lead­ing ques­tions and pre­con­ceived notions then you’ll only get the answers you were look­ing for.

Clarke then looks at how Aboriginal peoples saw their world. If you’re going to exam­ine the sky, it helps to know how the people describ­ing it saw it in rela­tion to the rest of the world. A com­mon fea­ture of abori­ginal cos­mo­logy is that the sky was seen as con­nec­ted to the land. Clarke refers to the sky as the “Land of the Dead” or the “Land to the West”, because spir­its are thought to travel to the west to enter the sky. The meth­ods of get­ting there var­ied. Tasmanians saw their foot tracks in the forest as lead­ing to the Milky Way. This reminds me a bit of the Greenlandic idea that the shaman could walk to the moon. In the far north the moon can roll across the hori­zon, so that it has a vis­ible con­nec­tion to the Earth. From that view the idea that the Milky Way is a foot track con­nec­ted to the Earth where it meets the hori­zon makes sense. Others have the idea that birds could trans­port people to the Skyworld, which again matches obser­va­tions of birds being between land and sky. Still more say that you can reach the Skyworld by climb­ing tall trees and get­ting help from a passing tornado.

The abori­ginal Skyworld seems to be a very richly described place. The abori­gin­als have no truck with celes­tial spheres. Their Skyworld has topo­graphy, trees and inhab­it­ants. The Skyworld is where the ancest­ors live, and so it’s a handy place to visit if you’re in need of a bit of ancient wis­dom. They should be easy enough to find as some of the ancest­ors are thought to be vis­ible as stars.

The iden­ti­fic­a­tion of ancest­ors in the sky brings a whole series of fur­ther factors. Kinship is import­ant in abori­ginal soci­ety and the same is true for the ancest­ors. Antares is Butt Kuee Tuukuung in south­w­est Victoria, and the fainter close stars are his wives. Brightness and loc­a­tion explains a lot of the other rela­tion­ships that Clarke lists. Time is also an issue. In north­ern Queensland the Evening Star is Dog and the Morning Star is Bitch. All these fea­tures are cat­egor­ised in clans and sec­tions just like the rest of the abori­ginal world includ­ing anim­als and plants on the land.

Opinion is divided on how the Sun and Moon return from the west to the east. For some people this is through a path in the under­world. The people of Arnhem land have a tale the Sun becomes a great fish and swims under the land through the ocean. That appeals to me at a nar­rat­ive level. Other regions have other tales and some include the pas­sage of stars beneath the earth as well as the Sun and Moon.

One of the inter­est­ing fea­tures that comes out of this paper is that the Aboriginal people seem to have a concept of stars, but not so much of stick-figure con­stel­la­tions. Clarke men­tions a sur­vey by Haynes that finds evid­ence of some faint stars being Unwala the Crab Ancestor [PDF], but not both­er­ing with Procyon and Regulus — two much brighter stars close by. My reac­tion was that maybe this shouldn’t be too much of a sur­prise. If a bright star is an ancestor then it’s an indi­vidual not part of a lar­ger fig­ure. There are already kin­ship con­nec­tions between stars so the idea of Greco-Roman style con­stel­la­tions is prob­ably a bit too con­fus­ing. Another factor is that because the Milky Way is so vis­ible, there are already plenty of dark-cloud con­stel­la­tions that actu­ally look like things. For example one patch of neb­ula in the Milky Way blots out the stars mak­ing the sil­hou­ette of an emu in the sky. That makes draw­ing stick fig­ures between stars an uncon­vin­cing altern­at­ive for con­stel­la­tions. But there are other bet­ter reas­ons too.

Clarke makes the point that col­our is very import­ant in abori­ginal cos­mo­lo­gies. One example he gives are the Arrente people of Central Australia who give more import­ance to red­dish or white stars than yel­low or blue stars. It won’t sur­prise you the same people value red ochres and white clays as sym­bols of power. Colour becomes more com­plic­ated when you exam­ine the Sun or Moon, which are red at the hori­zon but change col­our as they climb and fall. A red Sun seems to a par­tic­u­lar prob­lem as it’s a fem­in­ine sym­bol and red is a power­ful col­our. One tra­di­tion describes it as a kangaroo skin dress that is given to her by men who spend the night with her. The mottled face of the Moon seems to be explained by scars of con­flict, but the exact nature of the fight var­ies from region to region.

Clarke cov­ers time­keep­ing, espe­cially sea­son­al­ity in depth. The only thing I’ve found miss­ing here is when the day starts. Some cul­tures see it start­ing at sun­rise, oth­ers at sun­set but I’ve no idea if there’s a shared day concept in Aboriginal cul­ture. The Pleiades seem to be par­tic­u­larly import­ant in the turn­ing of the sea­sons [PDF]. Clarke notes that Tindale has fifty dif­fer­ent ver­sions of Pleiades myth­o­logy con­nect­ing them to chan­ging of the sea­sons. That might indic­ate a lot of dis­agree­ment, but the fact that so many abori­ginal cul­tures over such a large area are using the same gen­eral idea and dis­agree­ing on the details points to inter­con­nec­tion between peoples.

The sad­dest sec­tion is The Collapse and Rebirth of the Cosmos. Aboriginals did not pass­ively sit wait­ing for white set­tle­ment and news of the Europeans pre­ceded their arrival in many places. Clarke can show this is reflec­ted in their cos­mo­logy. The British arrived in the east and thanks to small­pox brought death with them. Visions of the Aurora Australis and met­eors were inter­preted as omens of dire times. Given the res­ults it’s easy to see how the arrival of the British could be seen as a cos­mic apo­ca­lypse.

The com­mon theme in this paper, apart from sheer vari­ety and oth­er­ness of abori­ginal astro­nomy is that this is also a con­tinu­ing tra­di­tion. I’m acutely aware I may have mixed up tenses in the descrip­tion because some of these ways of life have gone, while oth­ers are still alive. This life isn’t simply a rut that people return to, but a tra­di­tion that can adapt can appro­pri­ate new ideas, like Aboriginal beliefs about UFOs, or sci­entific dis­cov­er­ies. Clarke men­tions the met­eor­ite strike that cre­ated the Wolfe Creek Crater has been woven into tales of the Dreamtime.

Astronomically inspired indigenous art at the Ilgarijiri exhibition on display in Geraldton. Photo (cc) AstroMeg.
Astronomically inspired indi­gen­ous art at the Ilgarijiri exhib­i­tion on dis­play in Geraldton. Photo (cc) AstroMeg.

Good writ­ing can trans­port you to strange new places. Sometimes its an evoc­at­ive geo­graph­ical descrip­tion, but it can also show you the uni­verse in a new light. Astronomy can show the majesty of the cos­mos and the sheer scale of cre­ation. At the oppos­ite end of the scale you can go on safari with micro­scopic bac­teria far too small to be seen by the human eye. In the case of work like Clarke’s, it can be a guide to show how spe­cial the appar­ently mundane is. The night sky we see is more or less the same as seen by the abori­ginal peoples of Australia, allow­ing for some effects of lat­it­ude of the observer.

What I like about this paper is that at each step Clarke is link­ing back to the cul­ture that the astro­nomy is in. The fact that abori­ginal astro­nomers are inter­ested in the col­ours of stars is, by itself, a foible. Because Clarke makes that point that col­our is con­nec­ted to all sorts of ter­restrial sym­bol­ism and mean­ing then the con­nec­tions between sky and soci­ety become much more mean­ing­ful. Likewise the lack of con­stel­la­tions might be taken as a sign that Aboriginal peoples aren’t that inter­ested in many stars. Knowing about the kin­ship sys­tem shows how mis­taken that is, and that state­ments about the Skyworld are also strong polit­ical state­ments about life in the world below.

The many pages of ref­er­ences at the end of the art­icle are the icing on the cake, because this paper is very much an over­view. Any single sec­tion of the paper is a gate­way to many many more art­icles research­ing abori­ginal astro­nomy and cul­ture. You never want to take one author’s work as the last word on a sub­ject, but if you’re inter­ested in Australian indi­gen­ous astro­nomy you could do a lot worse than take Clarke’s art­icle as the start­ing point.

ResearchBlogging.orgClarke, P.A. (2007). An Overview of Australian Aboriginal Ethnoastronomy Archaeoastronomy: The Journal of Astronomy in Culture, XXI, 39–58 (Mendeley link)