Next message: Clive: "SURVEY OF INDIA"
What I found initially confusing with celestial navigation was that the
familiar names of stars were replaced with unfamiliar ones. An example:
Alpha Centauri, our closest stellar neighbour, is known as Rigil Kentaurus,
for reasons still unclear (to me). It is one of the two stars known as the
Pointers, as they point towards the Southern Cross (Crux) and can be used
with Crux to find the direction of true south.
Incidentally, there is a star lying virtually directly over the South Pole,
like Polaris over the North, but unfortunately it is too dim for practical
purposes.
More star trivia: It is difficult to comprehend the proportions of celestial
distances, I like this example. If the earth was the size of a pea then the
sun would be the size of a basketball, and about 46 metres away ('from the
house to the street', as I explained it to our children - we have a long
driveway). But the nearest star is another basketball - in Singapore !
(distance from Sydney). Though for further objects, nebulae and so on, the
comparison breaks down, as the distances are still astronomical.
