Tuesday, November 6, 2012

Total solar eclipse to take place November 14/13, 2012 in the southern hemisphere

We're currently about one week away from a new moon, when the moon passes between the earth and the sun (see this previous post for discussion and video related to new moon, as well as this previous post for discussion and a sketch related to the phenomenon of new moon). 

Because the path of the moon's orbit is not perfectly aligned with the plane of earth's orbit around the sun (the ecliptic plane), the moon does not blot out the sun every time its orbit takes it between earth and the sun.  However, there are two points where the plane of the moon's orbit intersects with the plane of the earth's orbit around the sun -- these are called the "lunar nodes."  When the moon happens to pass between the earth and the sun at the same time that its orbital plane brings it across the earth's ecliptic plane (at one of the two nodes), then we experience a solar eclipse.  

The two lunar nodes are discussed in greater detail in several previous posts -- see in particular "The lunar nodes and the nine-world cosmology" and also "An excellent website explaining the lunar nodes (with animation)."

Next week, as the moon passes between the earth and the sun, its orbit will also bring it through the plane of the ecliptic at a lunar node (in this case, the "ascending node," which is discussed in the two posts linked above).  This conjunction will create a total solar eclipse along the portion of the globe that happens to be pointed in the right direction when it takes place.  

Because the alignment of a solar eclipse can be thought of as a sort of "rifle barrel" phenomenon, in which your position as observer must be properly lined-up behind the "rear sight" of the moon as you look towards the "front sight" of the sun behind it, there will only be a narrow band of the earth's surface where an observer will be properly aligned to see the moon block out the sun completely for a total eclipse.  That band is shown in the map above, which is an interactive Google Map for this upcoming solar eclipse and which can be found at the NASA website page dedicated to this eclipse, here.

As you can see from the map, the path of this eclipse originates in a fairly remote area of Australia's Northern Territory, east of Darwin, Australia, in the Kakadu National Park, and then cuts across the Arafura Sea north of Australia before again intersecting the land, this time in Far North Queensland.  It will be the morning of 14 November there, although it will still be 13 November in the western hemisphere and in Europe.

In Far North Queensland, the turning of the earth will bring the total eclipse over the city of Cairns, Australia -- a major tourist destination and perhaps a good area to make your destination if you hope to view the total eclipse next week (jump in the car now, Kiwi).  It appears that the best places to see the eclipse might be along the Captain Cook Highway next to the Coral Sea, just north of Cairns itself (unless, of course, you can get onto a boat).

As the earth continues to rotate, the alignment of the total eclipse will aim the "rifle barrel" of totality along a track that goes out into the Pacific, passing north of the North Island of Aotearoa (New Zealand) and reaching the point of "Greatest Eclipse" (where the duration of totality surpasses four full minutes, almost twice as long as totality in the region of Cairns, Australia) in the ocean to the east of Rekohu (Chatham Island).  The path of the eclipse then continues over the trackless seas in the direction of South America, passing well to the south of Rapa Nui (Easter Island) and then comes to an end over the ocean more than five hundred miles to the west of Chile.

Unless you can make plans to view the eclipse from the ocean, then, it may be advisable to head towards Queensland if you wish to observe this total eclipse.

Here is a passage from author Jane Sellers describing the power of the moment of totality, from her well-known and important book Death of Gods in Ancient Egypt
A total eclipse is the most spectacular of all natural phenomena.  It is difficult to impress this on those who have only witnessed those that are partial. [. . .]

I have seen six total eclipses, three near the equator where the rotation of the earth prolongs all aspects of an eclipse.  The Diamond Ring Effects appeared to my unaided eye as they look in the photographs.  On all six occasions the emotional impact of this startling effect took me by surprise [. . .]
Anyone who has witnessed totality will understand how difficult it is to convey the sense of wonder that this phenomenon engenders.  After viewing totality on July 11, 1991, amateur astronomer Barry Slavin wrote 'I hardly know what I did.  My carefully laid plans were in ruins.  I could not take my eyes off that terrible wonderful thing there in the sky over our heads . . . It was every artist's conception of totality, but more brilliant, delicate, and finely etched than I could have ever imagined.'  The editors of the magazine Sky and Telescope followed this quote with the comment: 'In truth, we see totality not with our eyes but with our souls.'  36-39.
With a description like that, who can resist the urge to drop everything right now and start flying or driving towards Far North Queensland, or paddling towards the sea north or east of Aukland, to try to participate in the upcoming total solar eclipse?