h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I've been looking through my English translation of Ptolemy's Almagest to see the list of the 48 constellations known to the ancient Greeks. Unfortunately, my translation translates all the Greek names for the constellations into our modern names, so I don't know what the Greek called them.

I was delighted to find a copy on the internet of the complete Almagest in ancient Greek as a PDF file. It was only 17MB. I downloaded the whole thing and can now study it. This was published by a Greek scholar at the end of the 19th Century and is now out of copyright.

I don't speak ancient Greek, but I can compare the table in English and Greek and figure out which bits are the names of the constellations. I've discovered some interesting facts such as that the ancients called Libra "The Claws" as it was the claws of the Scorpion. Libra and Scorpius should really have been one constellation, but that would have played merry hell with their ideas of symmetry.

>>I've been looking through my English translation of Ptolemy's Almagest

Oh, off!









( Gotta admit...it's a seriously y opening line. )

I'm seriously impressed that I already knew that - the alpha-designated star of Libra is called Zubenelgenubi, (Arabic meaning 'the southern claw')

Are you going to write an entry about the ancient Greek constellations?

At the moment all I've got is a list of names. I'm not sure that there's enough there to make an interesting entry. But I'll continue reading.

A2751518

Fascinating stuff - I look forward to seeing how this develops

Apologies if this is a stupid question (I'm not an astronomer). Ptolemy described 97% of the night sky in 48 constellations, but we now describe 100% of it in 88 constellations. So we have invented 40 or so new constellations since. Now, were these 40 included within Ptolemy's constellation boundaries (ie, did he describe his within contiguous areas of sky) or are they filling in gaps between them?

Ptolemy's constellations had gaps in between them, and these have been filled in with faint constellations which don't really deserve the name, such as Lynx. One of Ptolemy's constellations was considered too big and was split up into four three new ones. And the are missing 3% has also been filled in.

An interesting coincidence:

The Greek name for Gemini is Didymôn, a word I had never seen before, which I presume means twins. Yesterday I saw a window-sticker in a car "Say No to Didymon". No idea what that was about.

Actually I've just checked my figures and it is 7% of the sky which is not visible from Alexandria.

Didym- is a medical prefix denoting the testacles...

Yes, I know that doesn't explain anything.

Didymus, on the other hand, was a noted Alexandrian scholar of the 1st Century BC. His nicknames were Chalkenteros (‘Brazen-bowels’)* and Bibliolathas (‘Book-forgetting’).

* Answers on a postcard, please.

Maybe it was something to do with Ken Dodd.

He seems to have been an adulterous acquantance of Diogenes. But I'm sticking with the Ken Dodd theory. Tatifilarious!

I must admit I was hearing Ken Dodd's voice in my head with the way this conversation was going...

Maybe your car sticker said 'Stop the Didymo' - it's a form of invasive algae. I'm not sure if it's the same as 'Red Tide' which is currently threatening Cornwall (I saw a few dead fish in St Ausell Bay last week).

Someone's campaigning against tides? They must be complete Cnuts.

Yes We Canute!

According to Wikipedia, Didymo is also known as 'rock snot'. That's interesting.

(This is rapidly turning into an episode of The Burke Special)

All we need to do is put on a safari jacket , leap around and gibber inanely.

I can manage the last part, anyway.