Big Dipper and the Seasons

June 17, 2020

Composizione 4 stagioni inglese picc (002)

Photographer: Giorgia Hofer 
Summary Author: Giorgia Hofer 

Featured above are four photos that I took of the Big Dipper in order to highlight how this familiar asterism of Ursa Major rotates in the sky during the four seasons. All photos were taken from locations in Italy in 2019 (summer and fall) and 2020 (winter and spring), captured between 8:00 p.m. and 10:00 p.m. every 3 months. Because the stars continue to move overhead all night long (or, more accurately, Earth continues to spin), the Big Dipper will change appearance over the course of any given night.

Spring is the season when the Big Dipper is seen highest in the sky -- almost at the zenith and upside down as viewed looking north. During the summer, the Big Dipper presents itself with its handle facing upwards. In autumn, the Dipper is closest to the horizon. During winter, the Big Dipper begins to distance itself from the horizon, presenting the handle facing downwards.

Photo Details: Nikon D750 camera; Samyang 12 mm fisheye lens; 12 mm focal length. Spring: from Lorenzago di Cadore, Italy; 10 seconds exposure; ISO 5000; f/2.8. Summer: from Tre Cime di Lavaredo, Italy; 30 seconds exposure; ISO 1000: f/3.2. Fall: from Piana Mount, Italy; 15 seconds exposure; ISO 6400; f/2.8. Winter: from Misurina, Auronzo di Cadore, Italy; 4 seconds exposure; ISO 1600; f/2.8.