Rome's Pantheon may have been built as a massive sundial

[Viggen]

It is one of the best preserved buildings from the Roman world, a 2,000-year-old testament to the immense power and wealth of the empire.But mystery has always surrounded what lies behind the unusual design of the Pantheon, a giant temple in the heart of Rome that was built by the Emperor Hadrian.Now experts have come up with an intriguing theory

[caesar novus]

Just some unrelated observations... I think the Pantheon's exterior is ugly, hulking, and of awkward proportions. However it was pointed out to me that it was originally tightly surrounded by wings of related buildings, and thus mainly seen from inside perspectives.

 

Sorry, but I also think the lower level interior clashes with the Roman vibe. It's sort of Catholic baroque, but I hear the original interior look is recreated in a room of the Vatican. I vaguely recall this as pagan grandiose, but didn't appreciate it too well because the crowds are at a particular chokepoint there. Also it looks a bit new and stagey, so I didn't make the connection until hearing about it afterwards (maybe someone can post a picture?).

[Northern Neil]

Just some unrelated observations... I think the Pantheon's exterior is ugly, hulking, and of awkward proportions.

Oh no, sir! I refute your argument thus. I think I have come across the sundial hypothesis before. The oculus does indeed enable one to use the building as a sundial, and quite an accurate one, as the building faces due south. Probably an intended consequence of the otherwise functional oculus.

If, as CN says the exterior was surrounded by wings of related buildings, an interesting thought occurs. Maybe the Pantheon is the prototype for late Roman and Byzantine churches, and ultimately mosques?

Edited August 1, 2011 by Northern Neil

[caesar novus]

If, as CN says the exterior was surrounded by wings of related buildings, an interesting thought occurs. Maybe the Pantheon is the prototype for late Roman and Byzantine churches, and ultimately mosques?

I believe I saw the whole pantheon temple complex depicted in this Yale class session http://academicearth.org/lectures/hadrians-pantheon-and-tivoli-retreat

[GhostOfClayton]

Apparently, the columns under the portico were shipped in from a remote Egyptian quarry. When they arrived, they were significantly shorter than ordered. That's why there's that odd looking line just above the pediment.

Edited August 1, 2011 by GhostOfClayton

[caesar novus]

The oculus does indeed enable one to use the building as a sundial, and quite an accurate one, as the building faces due south.

It faces north, so the sunbeam can slant in towards the entrance from the south. I found a picture of the supposed Vatican reconstruction of the original pantheon interior, and it is obviously just a loose allusion or a mistake of intentions by a guidebook:

[Northern Neil]

It faces north, so the sunbeam can slant in towards the entrance from the south.

sorry - yes, that was a typo - I have actually visited it! Anyway, my point being, as it is aligned north - south, as opposed to being scewed or slightly offset, it does indeed function as a sundial. This I find no great mystery; the same applies to the building I work in, and its skylight in the dining room!

 

Ok, now to watch the Yale lecture...

[Ursus]

Old News: http://www.unrv.com/forum/topic/9382-was-the-pantheon-a-sundial/

[caesar novus]

my point being, as it is aligned north - south, as opposed to being scewed or slightly offset, it does indeed function as a sundial.

There is a pantheon webcam sometimes panning the entrance from about the same angle of your photo here (although mounted lower) where you should be able to see the below effect (if not the March equinox thingy). Easily found on the web, although I like to use the android app "rome webcam" in spite of it falling out of date and not showing other Roman sites very well.

 

A similar effect is seen on April 21, which the Romans celebrated as the founding date of their city, when at midday the sun beam strikes a metal grille above the doorway, flooding the colonnaded courtyard outside with light.

Edited August 5, 2011 by caesar novus

[JGolomb]

"The precise calculations made in the positioning and construction of the Pantheon mean that the size and shape of the beam perfectly matches, down to the last inch, a semicircular stone arch above the doorway."

 

Has anyone been able to find an image of what's referenced above? I can't find any clear pix of the doorway to the Pantheon...

 

J

[Maladict]

Dozens of pictures of the pantheon in my collection, and only one that shows the area above the doorway.

Well, better than nothing, I guess.

Edited August 18, 2011 by Maladict

[Melvadius]

This abstract in Astronomical Heritage by Guilio Magli may be of interest as it includes a photograph of the main 'hierophany' on 21 April when the area above the door is illuminated by light from the oculus. A similar event apparently occurs during the August equinox.

 

 

EDIT: BTW the article has a link to the full thesis by Magli and Hannah via Cornell University library 'The role of the sun in the Pantheon

[JGolomb]

Ahh...I see what they were getting at now. Doesn't seem to perfectly fit that rounded top lintel, but I get the point.

 

Good grab...thanks.