On 27 November 1755 a strong earthquake occurred in Morocco. The seismic event had an estimated magnitude 6.5 to 7.0.
The estimated primary trigger of this seismic event is a quadruple conjunction with Venus, the Sun, Mercury and Mars on 27 November 1755.
On 27 November 1755 a rare near perfect quadruple conjunction occurred with Venus, the Sun, Mercury and Mars, resulting in four conjunctions involving these celestial bodies within 2.5 hours (from 05:48 to 08:15 UTC). A convergence of critical planetary geometry first occurred on 23-25 November when a planetary conjunction with the Sun, Mercury and Earth was followed by a pair of planetary right angles with Mercury and Venus involving Uranus. In addition, a series of lunar conjunctions occurred from 23 to 27 November involving all outer planets, but Jupiter.
Venus-Mercury-Earth 1755-11-21, 08:04:55 68°12'09" Sun-Mercury-Earth 1755-11-23, 21:52:50 64°46'35" Mercury-Sun-Venus 1755-11-27, 05:48:50 265°46'33" Sun-Mercury-Mars 1755-11-27, 06:16:18 85°53'46" Venus-Mercury-Mars 1755-11-27, 06:39:35 85°52'52" Venus-Sun-Mars 1755-11-27, 08:15:32 85°56'14" Sun: Mercury-Neptune 1755-11-20, 06:36:37 90°00'00" Earth: Venus-Mars 1755-11-20, 07:37:19 135°00'00" Venus: Mars-Saturn 1755-11-21, 11:23:30 135°00'00" Sun: Mercury-Jupiter 1755-11-21, 20:25:08 135°00'00" Sun: Venus-Uranus 1755-11-22, 01:06:14 90°00'00" Sun: Venus-Saturn 1755-11-22, 05:45:19 45°00'00" Earth: Mercury-Mars 1755-11-22, 08:16:47 135°00'00" Mercury: Venus-Saturn 1755-11-24, 02:53:13 45°00'00" Mercury: Venus-Uranus 1755-11-24, 04:52:29 90°00'00" Mercury: Mars-Neptune 1755-11-24, 19:52:07 45°00'00" Venus: Mercury-Uranus 1755-11-25, 04:34:10 90°00'00" Earth: Venus-Saturn 1755-11-25, 13:00:47 45°00'00" Venus: Mercury-Saturn 1755-11-25, 13:37:26 135°00'00" Mercury: Saturn-Uranus 1755-11-25, 18:15:50 45°00'00" Sun: Mercury-Uranus 1755-11-25, 22:40:42 90°00'00" Sun: Mercury-Saturn 1755-11-26, 00:07:20 135°00'00" Earth: Venus-Uranus 1755-11-26, 14:05:18 90°00'00" Earth: Mercury-Jupiter 1755-11-27, 02:32:02 45°00'00" Venus: Mercury-Neptune 1755-11-27, 12:30:34 45°00'00" Sun: Mercury-Neptune 1755-11-27, 12:44:39 45°00'00" Mercury: Venus-Neptune 1755-11-27, 23:39:24 135°00'00" Venus: Mars-Neptune 1755-11-28, 04:01:53 45°00'00" Sun: Venus-Neptune 1755-11-28, 09:28:11 135°00'00" Venus: Mercury-Jupiter 1755-11-28, 14:51:51 90°00'00" Sun: Mercury-Jupiter 1755-11-29, 03:00:42 90°00'00" Moon-Earth-Mercury 1755-11-20, 01:07:45 249°42'10" Earth-Moon-Mars 1755-11-23, 12:47:29 111°52'11" Moon-Earth-Saturn 1755-11-24, 01:22:12 298°21'19" Earth-Moon-Neptune 1755-11-25, 07:52:01 134°19'40" Moon-Earth-Uranus 1755-11-27, 15:40:33 344°48'06" Earth-Moon-Jupiter 1755-11-29, 21:19:46 196°07'13" Earth: Moon-Saturn 1755-11-20, 07:50:34 135°00'00" Earth: Moon-Uranus 1755-11-20, 11:20:03 90°00'00" Earth: Moon-Neptune 1755-11-21, 16:26:17 45°00'00" Earth: Moon-Jupiter 1755-11-22, 23:15:39 90°00'00" Earth: Moon-Sun 1755-11-23, 07:31:43 135°00'00" Earth: Moon-Mercury 1755-11-23, 10:02:00 135°00'00" Earth: Moon-Venus 1755-11-23, 21:38:01 135°00'00" Earth: Moon-Uranus 1755-11-24, 04:07:57 135°00'00" Earth: Moon-Jupiter 1755-11-26, 14:02:21 45°00'00" Earth: Moon-Mercury 1755-11-26, 15:12:16 90°00'00" Earth: Moon-Mars 1755-11-27, 01:04:47 45°00'00" Earth: Moon-Sun 1755-11-27, 03:37:32 90°00'00" Earth: Moon-Saturn 1755-11-27, 13:39:15 135°00'00" Earth: Moon-Venus 1755-11-27, 18:16:41 90°00'00" Earth: Moon-Neptune 1755-11-28, 16:58:45 45°00'00" Earth: Moon-Mercury 1755-11-29, 16:34:47 45°00'00"