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23 Sep 2016

The #Season has changed… but why? (#NASA)


Title: The #Season has changed… but why?.

Subject: Astronomy, movement of the Earth around its orbit.

Source: NASA, full page: (LINK). via Instagram.

Code: [ EDU ]



First Day of Fall 2016 One of the most frequently misunderstood concepts in science is the reason for Earth’s seasons. As we experience the September equinox today we thought we’d offer a space-based view of what’s going on. Around 6 a.m. local time each day, the Sun, Earth, and any geosynchronous satellite form a right angle, affording a nadir (straight down) view of the terminator, the edge between the shadows of nightfall and the sunlight of dusk and dawn. The shape of this line between night and day varies with the seasons, which means different lengths of days and differing amounts of warming sunshine. (The line is actually a curve because the Earth is round, but satellite images only show it in two-dimensions.) The Spinning Enhanced Visible and Infrared Imager (SEVIRI) on EUMETSAT's Meteosat-9 captured these four views of Earth from geosynchronous orbit. The images show how sunlight fell on the Earth between September 19, 2010 and September 19, 2011. Each image was taken at 6:12 a.m. local time. Credit: NASA images and animation by Robert Simmon, using data ©2010 EUMETSAT #equinox #fall #nasagoddard -- rebecca

Un video pubblicato da NASA Goddard (@nasagoddard) in data:


Keywords: NASA; Educational Materials; Earth; Astronomy.