PDA

View Full Version : Question about constellation Hercules.



Tucson_Tim
2007-May-30, 08:45 PM
My old astronomy book describes Hercules as standing with his left foot on the head of the dragon (Draco). This is the way I've always pictured Hercules: Upright when standing "over" Draco and over Polaris.

But all my newer books show Hercules as upright with Draco over his head.

Right now, in the early evening, Hercules is lying on his side (from my viewpoint at +32 degrees) and is slowly rotating up to stand upright.

So, which orientation is correct? It really only matters when I'm pointing out Hercules to some non-astronomy folks and they ask where is his head, where are his legs, etc.

Crimson
2007-May-31, 12:41 AM
All my charts show the head of Hercules as the star farthest from Draco. Also, the name of that star--Alpha Herculis--is Ras Algethi, which means "kneeler's head." So I'd say your old book is right.

I hope the IAU didn't screw this one up too.

Tucson_Tim
2007-May-31, 12:56 AM
Here's the wikipedia entry which shows two different visualizations but both have the head of Hercules close to Draco. This means that when you could see him in his entirety, say from 30-40 degrees north, he would be upside down.

http://en.wikipedia.org/wiki/Hercules_constellation

I know it doesn't matter, astronomically, but it sure is bugging me... :confused:

Tucson_Tim
2007-May-31, 12:57 AM
I hope the IAU didn't screw this one up too.

This has happened before?

Palomar
2007-May-31, 03:53 PM
So, which orientation is correct? It really only matters when I'm pointing out Hercules to some non-astronomy folks and they ask where is his head, his legs are, etc.

...which is why I prefer observing in solitude. :lol: If husband's outdoors with me, he doesn't ask many questions.

Don't you just love the constellations so close to the circumpolar line? :P

Having checked an old star atlas of mine: Draco is above Hercules, who is depicted as being upside-down in an intense crouching position, i.e. the head of Draco is skimming Hercules' knees.

Hope that helps.

And if your companions get too demanding for specifics, distract them with M13 (and don't mention Bootes or it'll be another explanation session) ;)

Tucson_Tim
2007-May-31, 04:14 PM
...which is why I prefer observing in solitude. :lol: If husband's outdoors with me, he doesn't ask many questions.

Don't you just love the constellations so close to the circumpolar line? :P

Having checked an old star atlas of mine: Draco is above Hercules, who is depicted as being upside-down in an intense crouching position, i.e. the head of Draco is skimming Hercules' knees.

Hope that helps.

And if your companions get too demanding for specifics, distract them with M13 (and don't mention Bootes or it'll be another explanation session) ;)

So, it seems the old star atlases show Hercules standing (or kneeling) on the dragon, and the newer atlases show him just the opposite, with his head close to the dragon. Hmmm. :think:

tdvance
2007-May-31, 05:25 PM
I have a hypothesis--

Truly, the traditional view of Hercules is with Alpha at the head and, to quote, I think it was Herschel?, "Messier 13 on his buttocks". Then, a man named Rey published a book called "The Constellations, a new way to see them" or something close to that, in which he redrew most of the constellations to make the pictures fit the names in an easy-to-see manner. In particular, he flipped Hercules upside down so that Messier 13 is now on his head. Other changes include flipping the great bear left to right so the handle of the big dipper, which used to be his (er, her, it was a mama bear I think) tail now became the bear's nose. Personally, I like some of H. A. Rey's renditions, but not all of them. I think his Gemini works very well, fitting the traditional interpretation of the twins, but I never liked the bold changes such as Hercules and Ursa Major.

Tucson_Tim
2007-May-31, 05:29 PM
I have a hypothesis--

Truly, the traditional view of Hercules is with Alpha at the head and, to quote, I think it was Herschel?, "Messier 13 on his buttocks". Then, a man named Rey published a book called "The Constellations, a new way to see them" or something close to that, in which he redrew most of the constellations to make the pictures fit the names in an easy-to-see manner. In particular, he flipped Hercules upside down so that Messier 13 is now on his head. Other changes include flipping the great bear left to right so the handle of the big dipper, which used to be his (er, her, it was a mama bear I think) tail now became the bear's nose. Personally, I like some of H. A. Rey's renditions, but not all of them. I think his Gemini works very well, fitting the traditional interpretation of the twins, but I never liked the bold changes such as Hercules and Ursa Major.

Thanks! Good info. I know in the scheme of things it doesn't matter but in a way it is re-writing history - how the ancients saw the stars...