September 2015 lunar eclipse


A total lunar eclipse occurred at the Moon’s descending node of orbit on Monday, September 28, 2015, with an umbral magnitude of 1.2774. A lunar eclipse occurs when the Moon moves into the Earth's shadow, causing the Moon to be darkened. A total lunar eclipse occurs when the Moon's near side entirely passes into the Earth's umbral shadow. Unlike a solar eclipse, which can only be viewed from a relatively small area of the world, a lunar eclipse may be viewed from anywhere on the night side of Earth. A total lunar eclipse can last up to nearly two hours, while a total solar eclipse lasts only a few minutes at any given place, because the Moon's shadow is smaller. Occurring only about 5 hours after perigee, the Moon's apparent diameter was larger.
This lunar eclipse is the last of a tetrad, with four total lunar eclipses in series, the others being on April 15, 2014; October 8, 2014; and April 4, 2015.
The Moon appeared larger than normal, because the Moon was just 1 hour past its closest approach to Earth in 2015 at mid-eclipse, sometimes called a supermoon. The Moon's apparent diameter was larger than 34' viewed straight overhead, just off the coast of northeast Brazil.
The total lunar eclipse was darker than expected, possibly due to ash left behind from eruptions of the Calbuco volcano in April 2015.

Background

A lunar eclipse occurs when the Moon passes within Earth's umbra. As the eclipse begins, Earth's shadow first darkens the Moon slightly. Then, the shadow begins to "cover" part of the Moon, turning it a dark red-brown color. The Moon appears to be reddish because of Rayleigh scattering and the refraction of that light by Earth's atmosphere into its umbra.
The following simulation shows the approximate appearance of the Moon passing through Earth's shadow. The Moon's brightness is exaggerated within the umbral shadow. The northern portion of the Moon was closest to the center of the shadow, making it darkest, and most red in appearance.

Supermoon

This eclipsed Moon appeared 12.9% larger in diameter than the April 2015 lunar eclipse, measured as 29.66' and 33.47' in diameter from Earth's center, as compared in these simulated images.
A supermoon is the coincidence of a full moon or a new moon with the closest approach the Moon makes to the Earth on its elliptical orbit, resulting in the largest apparent size of the lunar disk as seen from Earth. This was the last supermoon lunar eclipse until January 31, 2018.

Visibility

The eclipse was completely visible over eastern North America, South America, west Africa, and western Europe, seen rising over western North America and the eastern Pacific Ocean and setting over east Africa, eastern Europe, and west and central Asia.

Timing

† The Moon was not visible during this part of the eclipse in this time zone.
* The penumbral phase of the eclipse changes the appearance of the Moon only slightly and is generally not noticeable.

Eclipse details

Shown below is a table displaying details about this particular lunar eclipse. It describes various parameters pertaining to this eclipse.
ParameterValue
Penumbral Magnitude2.23071
Umbral Magnitude1.27744
Gamma−0.32960
Sun Right Ascension12h17m08.9s
Sun Declination-01°51'20.9"
Sun Semi-Diameter15'57.6"
Sun Equatorial Horizontal Parallax08.8"
Moon Right Ascension00h17m33.6s
Moon Declination+01°32'03.6"
Moon Semi-Diameter16'44.5"
Moon Equatorial Horizontal Parallax1°01'26.6"
ΔT67.8 s

Eclipse season

This eclipse is part of an eclipse season, a period, roughly every six months, when eclipses occur. Only two eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months 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.
September 13
Ascending node
September 28
Descending node
Partial solar eclipse
Solar Saros 125		Total lunar eclipse
Lunar Saros 137

Related eclipses

Eclipses in 2015

Saros 137

Tritos series

Inex series

Half-Saros cycle

A lunar eclipse will be preceded and followed by solar eclipses by 9 years and 5.5 days. This lunar eclipse is related to two annular solar eclipses of solar saros 144.
September 22, 2006October 2, 2024