Supermoon of September 28, 2015

October 01, 2015



Photographers: Top - Miguel Claro; Bottom - Chris Kotsiopoulos
Summary Authors: Miguel Claro; Chris Kotsiopoulos; Jim Foster

The total lunar eclipse of September 28, 2015, coincided with a lunar perigee (supermoon). The two views above show the sequence of this eclipse as observed from a rugged volcanic ridge on La Palma, Canary Islands, Spain and from a natural limestone arch (Durdle Door) on the Jurassic Coast near Lulworth, England, respectively.

Because it's closer to Earth than other full Moons, a supermoon passes slightly deeper into the Earth's shadow and hence its color can appear redder than non-supermoon eclipses -- see close-up in the top image. At closest approach the Moon is 225,291 mi (362,570 km) distant. It's 251,910 mi (405,410 km) away at its furthest approach. Thus, the difference in distance results in the perigee full Moon being about 25 -30 percent brighter than the apogee full Moon. However, it may only be less than 10 percent brighter than a normal full Moon. Note that the dates of apogee and perigee don't match the phases of the Moon, so only occasionally (about once a year) will the nearest Moon be in the full phase.