The Neptune Line in Astrocartography

Obama's birth certificate puts him in Honolulu at 7:24 PM on August 4, 1961, and for that moment (05:24 UTC) Neptune stood at 8°36′ Scorpio. The lines below come from the site's API, the same request the astrocartography map sends for his chart, with each point verified offline and the distance from every listed city to each line measured.

Uranus did not keep to the orbit calculated for it, and in 1846 Urbain Le Verrier in Paris worked out where an unseen planet would have to be to pull it off course. Johann Galle, helped by Heinrich d'Arrest, looked at that spot from the Berlin Observatory on September 23, 1846 and found Neptune within about a degree of the prediction; John Couch Adams in Cambridge had made a similar calculation. Neptune had in fact been seen long before: Galileo's drawings from December 1612 and January 1613 record it as a fixed star near Jupiter. Like Uranus, Neptune has no place in traditional astrology, and its meanings, from the sea god's name to the themes of dissolution and illusion, are modern.

A full circuit of the zodiac takes Neptune about 165 years, some 14 years in each sign, and in 1961 it was in Scorpio. It moves so slowly that a birth one day later, at the same clock time, would shift its lines only 0°58′, nearly all of it the difference between a solar day and the Earth's turn against the stars. At Obama's birth it had just stationed: it turned direct at 8°32′ Scorpio on July 20, 1961 and was moving about 30 seconds of arc a day. It would not turn retrograde again until February 13, 1962.

Neptune's orbit is tilted less than two degrees, and in our 1900 to 2050 scan its latitude never went past 1°49′. Obama was born when Neptune was close to that limit, 1°46′ north, so his Neptune lines are a fair test of what the zodiacal method does to a slow outer planet. The answer is: not much, but not nothing. Drawn from Neptune itself (in mundo), as Jim Lewis drew them, the meridian lines would move 0°34′ east, about 65 km at the equator; the curved lines would shift as much as 220 km at 60° N:

Compare his Moon, whose latitude of 5°14′ moves its rising line 731 km at 60° N. For Neptune the cities hardly change: drawn in mundo, the rising line still passes Yangon, Xining and Ulaanbaatar, and the setting line still runs past Houston, Dallas and Fort Worth. The birth time matters far more than the method, as the next section shows.

A slow planet does not make for stable lines, because the lines are carried around the globe by the Earth's rotation. Had Obama been born at 7:54 PM, every Neptune line would sit 7°31′ farther west. The MC line, empty Pacific in the real chart, would cross New Zealand through Auckland, Wellington and Christchurch. The IC line would leave Paris and Barcelona for Madrid, Tangier, Fes, Rabat and Casablanca. The rising line would move from Yangon to Dhaka and Kolkata, and the setting line from Texas to Mexico City, Guadalajara and, in Canada, Calgary.

So a birth time rounded to the half hour can put Neptune's lines in four different countries. Jim Lewis's orbs were wide enough to blur some of that: a quarter of an inch of his map in 1976, roughly 300 to 400 miles, and up to 700 miles in his 1982 handbook. At 700 miles, 715 of the site's cities (31%) fall inside that distance of one Neptune line or another. Narrower is more useful, and an accurate time most useful of all; the pre-filled map shows his real lines.