View at EarthSky Community Photos. | Susan Kelley in Chatfield State Park, Colorado, took this image of the sunset, crepuscular and anticrepuscular rays and the Earth’s shadow on February 19, 2022. Susan wrote: “Saturday evening’s sunset (3-photo panorama) with crepuscular and anticrepuscular rays arcing over the sky. West (left side of image) sunset crepuscular rays appearing to converge on the sun. East (right side of image) much more dramatic anticrepuscular rays appearing to converge in the sky directly opposite the sun. Photo was taken from Chatfield State Park facing north toward Denver, Colorado.” Thank you, Susan!
We’ve all seen crepuscular rays, or sunrays, converging on the sun. They appear as pillars of sunlight, all meeting at a single point, streaming up from the horizon or down through gaps in clouds. Next time you see them … turn around. You may get a glimpse of the more elusive anticrepuscular rays.
Jenney Disimon in Sabah, North Borneo, caught these anticrepuscular rays and a rising moon – and posted them to EarthSky Facebook – on June 4, 2015.
Tips for seeing anticrepuscular rays
To see anticrepuscular rays, you need to turn your back on the sunset. These rays appear to converge toward the antisolar point – that is, the point on the sky opposite the sun. If you want to see them, remember these three tips:
1. When you’re gazing at a beautiful sunset and see crepuscular rays, remember to look behind you to see if there are also anticrepuscular rays.
2. Look carefully, and wait a few minutes to see if they appear over time. Remember that anticrepuscular rays are generally fainter and more elusive than crepuscular rays.
3. You can see them at sunset, but you also can see them at sunrise. Just turn your back on the sun in either situation.
Like crepuscular rays, they are parallel shafts of sunlight from holes in the clouds, and their apparently odd directions are a perspective effect. Think of a long straight road; it converges toward the horizon, but turn around and it also converges to the opposite horizon. Crepuscular and anticrepuscular rays behave in the same way.
Anticrepuscular rays are not rare, but they must be sought carefully. When ordinary crepuscular rays are visible, turn around and search for their opposite numbers.
Helio C. Vital caught these anticrepuscular rays from Saquarema, 50 miles (80 km) east of Rio de Janeiro, Brazil.
Photo gallery
Scott Kuhn captured anticrepuscular rays as the moon was rising over Fort Mountain in northern Georgia.Laura Bavetz wrote, “I have seen anticrepuscular rays before, but this is the first time that I have been able to capture them.”Photo taken by Karl Diefenderfer in Quakertown, Pennsylvania.Photo via Kenneth G. Smith.A moonset in 2014. The sun is about to rise in the east, and these rays are seen in the west. Photo by Ted Schultz of Titusville, Florida.Anticrepuscular rays seen in the east at sunset, in Bermuda, by our friend Le-ann Perry. Notice the rising moon. Also, look in the lower right of this photo, where you can see a bit of Earth’s shadow over the sea.Our friend Joe Randall caught these anticrepuscular rays in August 2014.View at EarthSky Community Photos. | Jo-Ann Hem Lee in the community of Trincity – in the Caribbean island country of Trinidad and Tobago – captured this image at sunrise on October 9. 2020.Anticrepuscular rays by Guillaume “Astro GuiGeek” Doyen.View at EarthSky Community Photos. | On June 1, 2020, Tracey Gray captured anticrepuscular rays over Narrabeen in New South Wales, Australia.
Bottom line: If you want to see anticrepuscular rays, look carefully opposite the direction of the sun. They are most often seen at sunrise or sunset.
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