EarthHuman World

Anticrepuscular rays: How to see them

Anticrepuscular rays: Panorama of mostly barren landscape and road with orange glow and higher dark blue sky.
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.

Wide white rays in a blue sky with small full moon halfway up in the sky and a pagoda on the right.
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.

Wide light rays through sinister dark clouds over a mountain landscape.
Anticrepuscular rays – seen in the east at sunset – in Nevada. Shreenivasan Manievannan posted this photo on EarthSky Facebook in July 2014. Visit Shreeniclix Photography.

What are anticrepuscular rays?

Les Cowley of the great website Atmospheric Optics says:

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.

See photo of crepuscular rays extending across the entire sky at Les Cowley’s website

Pink rays converging in twilight with a road going into the distance.
Helio C. Vital caught these anticrepuscular rays from Saquarema, 50 miles (80 km) east of Rio de Janeiro, Brazil.

Photo gallery

Faint pink rays converging to a point above low twilit hills.
Scott Kuhn captured anticrepuscular rays as the moon was rising over Fort Mountain in northern Georgia.
Blue and pink rays converging to a dark line of twilight above brushy landscape.
Laura Bavetz wrote, “I have seen anticrepuscular rays before, but this is the first time that I have been able to capture them.”
White rays streaming through clouds with a flock of wild geese in flight.
Photo taken by Karl Diefenderfer in Quakertown, Pennsylvania.
Green and blue rays converging to horizon.
Photo via Kenneth G. Smith.
Pinky-gray rays converging on horizon with round bright full moon right in the center, all reflected in body of water.
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.
Pink rays converging over white buildings on a hilltop with small moon visible.
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.
Rays converging under storm clouds to the right with a partial rainbow in the middle of the photo.
Our friend Joe Randall caught these anticrepuscular rays in August 2014.
Twilight sky, divided diagonally into pink and blue.
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.
Slanted white rays converging to a pink and orange sunset.
Anticrepuscular rays by Guillaume “Astro GuiGeek” Doyen.
Blue sky over a town with rays emanating from the horizon.
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.

Posted 
February 22, 2022
 in 
Earth

Like what you read?
Subscribe and receive daily news delivered to your inbox.

Your email address will only be used for EarthSky content. Privacy Policy
Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.

More from 

Deborah Byrd

View All