The sunrise point (azimuth) along the eastern horizon changes slightly from day to day. This is due to the tilt of Earth's axis of rotation with respect to the plane of its orbit around the Sun. In both hemispheres, the sunrise azimuth moves northward from the first day of the December solstice until the first day of the June solstice, then returns southward until the first day of the December solstice.
The angular distance between sunrise azimuths at the solstices depends on latitude. At the equator, the angular distance is about 47° (twice Earth's axial tilt). The farther north or south from Earth's equator, the greater the angular distance. The angular distance increases dramatically as the latitude increases on either side of the equator, maxing out at 180° at the polar circles (about 66.5° N/S latitude). A good explanation of the math involved is here:
stevekluge.com/...
and a good visualization tool is here:astro.unl.edu/...
In 2023/24, I organized a group of 13 photographers to capture sunrise near the June solstice and the December solstice, at the equator, and north and south of the equator, to illustrate the angular distance between solstice sunrises as a function of latitude.
The goal was to capture 13 sunrise images near the June 2023 solstice and 13 sunrise images near the December 2023 solstice, near selected latitudes. Some difficulties delayed two of the shoots which forced extending the project to the June 2024 solstice. The selected latitudes were the equator and six latitudes about 10° apart north and south of the equator, to about 60°.
The image capture brief was simple:
- Photograph sunrise at a given latitude near the June solstice and near the December solstice.
- Use a camera sensor/lens combination that yields a very wide field or shoot a panorama.
- Choose a location with a view of the eastern horizon.
- The skyline and foreground are at the photographer's discretion.
- Aim the camera as close as possible to due East.
- Shoot sunrise with the Sun visible as low as possible above the horizon.
The project execution was a bit more complicated. Two factors had to be addressed when assembling the final composite image while still yielding a faithful photographic representation of the solstice sunrise azimuths. (1) Differences in camera lens/sensor combinations yielded different horizontal fields of view and pixel scales. (2) Differences in camera position and aiming between the solstices yielded different frames. In addition, not all photographers were able to shoot at the widest horizontal field of view which would mean some parts of the final composite image would be blank.
This video is the final result of combining 13 June solstice sunrise images and 13 December solstice sunrise images, to visually depict the angular distance between solstice sunrises as a function of latitude.
Composite Image
The final composite image and full details about how it was created is here:
www.flickr.com..."
Photographer Credits
The following people generously provided the images for the movie composite image. Thank you all for your efforts in obtaining the photos!
+60.0, Fort Smith CA, Mike Couvrette
www.tawbas.ca/
+53.5, Edmonton CA, Luca Vanzella
www.flickr.com...
+40.8, Manhattan US, Stan Honda
stanhonda.com/
+29.8, Houston US, Chris Prazak
www.cmpimage.com/
+20.7, Maui US, Rob Ratkowski
+10.6, Guanacaste CR, Luis Murillo Castillo
www.instagram....
- 0.2, Quito EC, Henri Leduc
www.henrileduc...
-12.4, Darwin AU, Geoff Whalan
www.flickr.com...
-23.7, Antofagasta CL
Farid Char austrinus.com/
Maglio Cordero ruhiscos.cl/
-29.0, Cambara do Sul BR, Egon Filter
/ egonfilter
-43.5, Christchurch NZ, Chris Pegman
capturingthesp...
-50.4, El Calafate AR, Alejandro Capelli
/ alejandro_capelli
-54.8, Ushuaia AR, Esteban Daniels
www.birdingush...
Негізгі бет Sunrise Solstice Across the Planet
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