A total solar eclipse occurred at the Moon's descending node of orbit on Wednesday, July 18, 1860, with a magnitude of 1.0500. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. A total solar eclipse occurs when the Moon's apparent diameter is larger than the Sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with the partial solar eclipse visible over a surrounding region thousands of kilometres wide. Occurring about 2.2 days before perigee (on July 20, 1860, at 19:15 UTC), the Moon's apparent diameter was larger.[1]
The path of totality was visible from parts of modern-day northwestern Oregon, Washington, northern Idaho, northwestern Montana, Canada, Spain, Algeria, Tunisia, Libya, Egypt, Sudan, and Eritrea. A partial solar eclipse was also visible for parts of North America, Europe, West Asia, North Africa, and West Africa.
The first coronal mass ejection may have been observed as coronal loops progressing during this total eclipse.[2]
Shown below are two tables displaying details about this particular solar eclipse. The first table outlines times at which the moon's penumbra or umbra attains the specific parameter, and the second table describes various other parameters pertaining to this eclipse.[3]
| First Penumbral External Contact | 1860 July 18 at 11:54:56.3 UTC | |
| First Umbral External Contact | 1860 July 18 at 12:57:13.1 UTC | |
| First Central Line | 1860 July 18 at 12:58:21.9 UTC | |
| First Umbral Internal Contact | 1860 July 18 at 12:59:31.0 UTC | |
| Equatorial Conjunction | 1860 July 18 at 14:09:18.4 UTC | |
| Ecliptic Conjunction | 1860 July 18 at 14:20:40.8 UTC | |
| Greatest Duration | 1860 July 18 at 14:24:54.3 UTC | |
| Greatest Eclipse | 1860 July 18 at 14:26:24.2 UTC | |
| Last Umbral Internal Contact | 1860 July 18 at 15:53:26.2 UTC | |
| Last Central Line | 1860 July 18 at 15:54:37.2 UTC | |
| Last Umbral External Contact | 1860 July 18 at 15:55:48.0 UTC | |
| Last Penumbral External Contact | 1860 July 18 at 16:57:54.9 UTC |
| Eclipse Magnitude | 1.05000 | |
| Eclipse Obscuration | 1.10249 | |
| Gamma | 0.54871 | |
| Sun Right Ascension | 07h52m23.3s | |
| Sun Declination | +20°56'51.5" | |
| Sun Semi-Diameter | 15'44.4" | |
| Sun Equatorial Horizontal Parallax | 08.7" | |
| Moon Right Ascension | 07h53m03.2s | |
| Moon Declination | +21°28'15.4" | |
| Moon Semi-Diameter | 16'18.0" | |
| Moon Equatorial Horizontal Parallax | 0°59'49.1" | |
| ΔT | 7.7 s |
See also: Eclipse cycle. This eclipse is part of an eclipse season, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by a fortnight.
The partial solar eclipses on March 4, 1859 and August 28, 1859 occur in the previous lunar year eclipse set, and the partial solar eclipse on November 21, 1862 occurs in the next lunar year eclipse set.
| Solar eclipse series sets from 1859 to 1862 | |||||||
|---|---|---|---|---|---|---|---|
| Ascending node | Descending node | ||||||
| Saros | Map | Gamma | Saros | Map | Gamma | ||
| 109 | February 3, 1859 Partial | −1.5659 | 114 | July 29, 1859 Partial | 1.2598 | ||
| 119 | January 23, 1860 Annular | −0.8969 | 124 | July 18, 1860 Total | 0.5487 | ||
| 129 | January 11, 1861 Annular | −0.1766 | 134 | July 8, 1861 Annular | −0.2231 | ||
| 139 | December 31, 1861 Total | 0.5187 | 144 | June 27, 1862 Partial | −1.0252 | ||
| 149 | December 21, 1862 Partial | 1.1633 | |||||
