Centrepoint

How Australian is this? We are sitting around a campfire, cooking a lamb roast, looking up at a wide open sky and stars coming out right in the middle of Australia.

What do we mean right in the middle? Actually that is a good question. For the Geeks amongst us (or should that be nerds – I’ve forgotten the distinction), this is probably one of the most mathematical centres. We are at the Lambert Centre, approximately 130km east of the nearest roadhouse and the guy behind the till there had never heard of it.

If you approximate Australia as a flat plane, then this would be the point it would balance on if we cut it out. It was calculated by taking 24000 points around the coastline of Australia at the mean high water mark, then taking the average position of all of the points contained within that coastline.

So that is what we mean as we eat this lamb roast in the Lambert Centre. But what other centres could there be? Well, as it turns out, plenty. For a start you could weight each point by the height above sea level and do a weighted average. That would give you the point at which a relief model of the continent would balance, and that would be a little south-east of here. You could also account for the curvature of the earth and that would give a slightly different result again. Or maybe you could go for something simple, and just go halfway between the north and south extremes of latitude, and the east and west extremes of longitude, and use that. Or you could draw a line between those two pairs of opposite points and work out where they intersect. Or you could find the point on the mainland which is the greatest distance from any point on the coastline. I’ll leave working out how to do that as an exercise for the reader.

So they are some of the possibilities. Tomorrow we’ll visit another. The Johnstone Geodetic Centre was the point arbitrarily chosen as the origin for all Australian surveys which is only 100km from here.

On the way here we discovered that the Mt Ebenezer Roadhouse is no more, which is a bit of a shame as I was planning on buying fuel there and they advertised aboriginal art from the nearby settlement. Fortunately we got scared when the sign outside Curtin Springs said next fuel 160km and so we went back, much to the joy of the children.

Lunch wound up being at the Stuart Highway intersection, which is at a roadhouse called Erldunda. This is activity central in this part of the world and especially so at lunchtime. No shortage of people queuing up for fuel just below $2 a litre. A fairly busy but standard outback settlement – highway intersection, caravan park and not much else.

We turned south from here to a town called Kulgera, which isn’t much bigger, but doesn’t have the caravan park. There we turned eastward on the Mt Dare road which skirts along just north of the SA/NT border, crosses over the Ghan railway line, and passes north of a Mt Cecil, which would be important for a fairly specialised audience.

The road into the Lambert Centre was pretty ordinary and it wouldn’t have surprised me if there was nobody around. There was however already a camper here, and a check of the visitors book showed that we were the sixth visitor for the day. Plenty of room for us to not see each other in the centre of this wide brown land.