On the 20th of May the Sun will be partially blocked by the Moon in a solar eclipse that will be visible from the western half of the
continental United States as the Sun is setting. Viewing the eclipse ranges from Asia across the north Pacific to the southwestern United States.
As this eclipse is occurring late in the day the local time for sunset will determine how much of the eclipse will be visible. The further west the
viewing is done from means the Sun is higher above the horizon and more of the eclipse event will be visible.
An annular solar eclipse occurs at the new Moon phase but unlike a total solar eclipse the apparent size of the Moon is smaller
than the Sun's apparent size and at mid-eclipse the Moon is not large enough to completely block the Sun and so there is a ring, annulus, of 'fire'
around the Moon.
Eclipses, like solar transits occur regularly. They have regular repetitive patterns that among other things allow for the precise
calculations for the event times you see on the web sites. One of the patterns, the Saros Cycle, is of particular interest to me and anyone else with
a birthday in May. The Saros Cycle is approximately 18 years and 11 days long and is the period of time between solar eclipses. In particular these
two solar eclipses are similar in the alignment and distances between the Earth, Moon, and the Sun. Since the two eclipses are separated by an uneven
amount the major difference between them is in where on the Earth the eclipse will be visible from.
One Saros Cycle ago, on my birthday in May 1994,
the shadow path of an Annular Solar Eclipse came from the west and after crossing the western United States passed right across my hometown of
Lee's Summit Missouri. The shadow path of the Annular Solar Eclipse of May 2012 likewise comes out the west however this time it ends further to the
west from my location and will not be visible from my home location. However that eclipse will be back in my neighborhood following four Saros
Cycles - unfortunately I may not live that long!
In the Kansas City area the eclipse begins when the Moon makes first contact with the Sun at approximately 7:26 pm CDT, and
sunset is at 8:29 pm CDT. There is not much time to see the earliest stages of the eclipse, even with a relatively flat western horizon.
Click here for more information about the May 20th Annular Solar Eclipse
