| Total eclipse | |||||||||||||||||
 Totality as viewed from Lomita, California | |||||||||||||||||
| Date | 31 January 2018 | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Gamma | −0.3014 | ||||||||||||||||
| Magnitude | 1.3155 | ||||||||||||||||
| Saros cycle | 124 (49 of 74) | ||||||||||||||||
| Totality | 76 minutes, 4 seconds | ||||||||||||||||
| Partiality | 202 minutes, 44 seconds | ||||||||||||||||
| Penumbral | 317 minutes, 12 seconds | ||||||||||||||||
| |||||||||||||||||
A total lunar eclipse occurred on 31 January 2018. The Moon was near its perigee on 30 January and as such may be described as a "supermoon", when the Moon's distance from the Earth is less than 360,000 km (223,694 miles). The previous supermoon lunar eclipse was in September 2015.[1]
During the total lunar eclipse of Wednesday, 31 January 2018, the Moon was 360,202 km (only 202 km to be a Super Full Moon) (223,819 mi) from the Earth. A blue moon occurs because there are 2 full moons in the same calendar month, or if there are 4 full moons in the same season (third of four is blue moon). As this supermoon was also a blue moon (the second full moon in a calendar month), it was referred to as a "super blue blood moon"; "blood" refers to the typical red color of the Moon during a total lunar eclipse. The 31 January 2018 lunar event was called 'Trifecta'.[2] This coincidence last occurred on 30 December 1982 for the eastern hemisphere,[3] and otherwise before that on 31 March 1866.[4][5] The next occurrence will be on 31 January 2037, one metonic cycle (19 years) later.
- ^ Cite error: The named reference
earthskywas invoked but never defined (see the help page). - ^ "'Super Blue Blood Moon' Coming Jan. 31, 2018". NASA. 18 January 2018. Retrieved 1 February 2018.
- ^ Blue moon, based on the previous full moon, was either on November 30 or December 1, 1982, based on time zones.
- ^ Rare 'Super Blue Blood Moon' Coming—First in 35 Years, National Geographic, January 29, 2018
- ^ Mathewson, Samantha (30 January 2018). "The Super Blue Blood Moon Wednesday Is Something the US Hasn't Seen Since 1866". Space.com. Retrieved 1 February 2018.