Monticello's Solar Arc
While Monticello's location is given as 38 00 30 N and 78 27 12 W, we can presume that is the house, and that the measuring point was intended to be 38 00 00 N and 78 30 00 W. See this page for a list of distances for different degrees of longitude and latitiude. At this location, the sun rises due east in March and September, and rises 31 degrees north (left) of due east in June, and 31 degrees south (right) of due east in December. (That is 59 degrees from due north and south.) Since the sun moves fastest near the equinoxes, the half way points between the solstices and equinoxes is not half way in degrees. The sun moves a little over 70 percent of the 31 degrees in half the time, so that the cross quarter days (sunrises and sunsets) occur at about 23 degrees from due east (north and south). This relates to the 23 degree diagonal grid set up by the lines within the pentagram in the map. http://www.geomancy.org/astronomy/orthographic-projections/solstice-equinox/index.html In order to figure out where 23 and 31 degree angles fall in the DC area we set a program up with Monticello's coordinates, and set the bearings. Remember that the top of the district is at 39 N and the Capitol is just west of 77 W. Some one name Cort Lindahl, using the name Geomantic Information Systems, suggests that the 'basal datum' as he calls it, for the layout of the DC map was a point located at Rose Hill Estates, on the east side of the Potomac River, in Maryland. 38 30 43 N 77 01 30 W. And that the map was somehow built arond this point? He also suggest that Monticello was aligned to the Rose Hill house, so that the June solstice sunrise occurs over Rose Hill as seen from Monticello. Note that work on Monticello began in 1768 and Rose Hill was bought in 1780, the house being built later . At the location of Washington DC, the sun rises 31 degrees north of due east at the solstices. The line between Monticello and Rose Hill is on a bearing of 23.7 degrees north of due east. This is the position of the cross quarter sunrises and sets in DC, not the solstices Cort. Note that this matches the bearing of the pentagram grid. To see where the sun does rise on the June solstice as seen from Monticello, we plug in its coordinates and set the bearing for 59 degrees. As this brought me close to Mt Vernon, I messed with the numbers to see what I could find out. Mt Vernon is located near (depends on who yuo ask) 38 42 40 N and 77 05 12 W . "Starting at 38 0 00 N Latitude, 78 30 00 W Longitude (Point 1), and going 89.90 miles at 58.00° (referenced to True North), the endpoint coordinates are 38 40 52 N , 77 5 11 W (Point 2). Mt Vernon appears to be the solstice target as seen from Monticello. Author: survivalcell (75.15.95.---) Date: 03-Jul-09 17:35 " You just said exactly what I'm saying. I'm measuring the angle from Monticello as it rises in relation to that point on June,21. like if you were shooting at the sun as soon as you could see it from Monitcello. By the time the sun rises above the visible horizon (which is the way astroarchaeologists measure sunrise) it is at the angle I sugggest. Have you ever been to Monticello or Washington D.C.?" Shooting at the sun as soon as you can see it? Consider the image at the top of the page and note that as we look at the sun rising in the east, it moves 'up and to the right' because it is going to be over our right shoulder at noon (or our right ear) depending on the date and latitude of the viewer. He is already 7 degrees to far right, and he is suggesting that we late til later to measure the angle, as the sun gets closer to due east!! Do I need to go to DC or Monticello or Rome to be able to understand this? "Archaeology is a soft science dude. You just spent alot of time thinking about how to disagree with me when you came to the same conclusion as me. I have had several people double check this. Ovasons observations are from Washington DC to sunrise not from monticello." From DC not Monticello? That is a difference of half a degree of latitude, and won't make that much differtnce Cort. Astronomy and Geometry are not soft science dude. The June solstice sunrises over Mount Vernon as seen from Monticello. Who are these people who checked your work? Above we see a page from Charles Westbrook's book "Talisman". That's tbe Capitol building at the center, the Ellipse on the left and Lincoln Square on the right. Notice that he has labeled each set of line summer and winter solstice, even though the lines ar not parallel, so we know that at least one set is not correct. I figure the angles from due east of the pairs to be about 21 and 27 degrees, so neither of these works, as the number that we want is 31 degrees. Not every one is good at this. Below we se another Westbrook page. The lines marked Taurus are at 23 degrees from due east and show where the sun rises in Taurus, at the cross quarter day. However, the sun only moves another 8 degrees beyond that in DC. The line marked Gemini is 38 degrees from due east, 7 degrees beyond the solstice station. DC Symbols Home Page

Monticello's Solar Arc

While Monticello's location is given as 38 00 30 N and 78 27 12 W, we can presume that is the house, and that the measuring point was intended to be 38 00 00 N and 78 30 00 W. See this page for a list of distances for different degrees of longitude and latitiude. At this location, the sun rises due east in March and September, and rises 31 degrees north (left) of due east in June, and 31 degrees south (right) of due east in December. (That is 59 degrees from due north and south.)
Since the sun moves fastest near the equinoxes, the half way points between the solstices and equinoxes is not half way in degrees. The sun moves a little over 70 percent of the 31 degrees in half the time, so that the cross quarter days (sunrises and sunsets) occur at about 23 degrees from due east (north and south). This relates to the 23 degree diagonal grid set up by the lines within the pentagram in the map.
http://www.geomancy.org/astronomy/orthographic-projections/solstice-equinox/index.html
In order to figure out where 23 and 31 degree angles fall in the DC area we set a program up with Monticello's coordinates, and set the bearings. Remember that the top of the district is at 39 N and the Capitol is just west of 77 W.

Some one name Cort Lindahl, using the name Geomantic Information Systems, suggests that the 'basal datum' as he calls it, for the layout of the DC map was a point located at Rose Hill Estates, on the east side of the Potomac River, in Maryland. 38 30 43 N 77 01 30 W. And that the map was somehow built arond this point? He also suggest that Monticello was aligned to the Rose Hill house, so that the June solstice sunrise occurs over Rose Hill as seen from Monticello. Note that work on Monticello began in 1768 and Rose Hill was bought in 1780, the house being built later .
At the location of Washington DC, the sun rises 31 degrees north of due east at the solstices. The line between Monticello and Rose Hill is on a bearing of 23.7 degrees north of due east. This is the position of the cross quarter sunrises and sets in DC, not the solstices Cort. Note that this matches the bearing of the pentagram grid.
To see where the sun does rise on the June solstice as seen from Monticello, we plug in its coordinates and set the bearing for 59 degrees. As this brought me close to Mt Vernon, I messed with the numbers to see what I could find out. Mt Vernon is located near (depends on who yuo ask) 38 42 40 N and 77 05 12 W . "Starting at 38 0 00 N Latitude, 78 30 00 W Longitude (Point 1), and going 89.90 miles at 58.00° (referenced to True North), the endpoint coordinates are 38 40 52 N , 77 5 11 W (Point 2). Mt Vernon appears to be the solstice target as seen from Monticello.
Author: survivalcell (75.15.95.---)
Date: 03-Jul-09 17:35
" You just said exactly what I'm saying. I'm measuring the angle from Monticello as it rises in relation to that point on June,21. like if you were shooting at the sun as soon as you could see it from Monitcello. By the time the sun rises above the visible horizon (which is the way astroarchaeologists measure sunrise) it is at the angle I sugggest. Have you ever been to Monticello or Washington D.C.?"
Shooting at the sun as soon as you can see it? Consider the image at the top of the page and note that as we look at the sun rising in the east, it moves 'up and to the right' because it is going to be over our right shoulder at noon (or our right ear) depending on the date and latitude of the viewer. He is already 7 degrees to far right, and he is suggesting that we late til later to measure the angle, as the sun gets closer to due east!! Do I need to go to DC or Monticello or Rome to be able to understand this?
"Archaeology is a soft science dude. You just spent alot of time thinking about how to disagree with me when you came to the same conclusion as me. I have had several people double check this. Ovasons observations are from Washington DC to sunrise not from monticello."
From DC not Monticello? That is a difference of half a degree of latitude, and won't make that much differtnce Cort. Astronomy and Geometry are not soft science dude. The June solstice sunrises over Mount Vernon as seen from Monticello. Who are these people who checked your work?

Above we see a page from Charles Westbrook's book "Talisman". That's tbe Capitol building at the center, the Ellipse on the left and Lincoln Square on the right. Notice that he has labeled each set of line summer and winter solstice, even though the lines ar not parallel, so we know that at least one set is not correct.
I figure the angles from due east of the pairs to be about 21 and 27 degrees, so neither of these works, as the number that we want is 31 degrees. Not every one is good at this. Below we se another Westbrook page. The lines marked Taurus are at 23 degrees from due east and show where the sun rises in Taurus, at the cross quarter day. However, the sun only moves another 8 degrees beyond that in DC. The line marked Gemini is 38 degrees from due east, 7 degrees beyond the solstice station.

DC Symbols Home Page