Crepuscular Rays Seen From Space

[/caption]

Seeing crepuscular rays on Earth is a somewhat rare event, as conditions have to be just right at either sunset or sunrise for the Sun’s rays to appear as though they are diverging outward from the Sun. But seeing them from space is even more rare.

This picture taken by an astronaut on the International Space Station provides an unusual viewing perspective from above of crepuscular rays. Why are they parallel in this picture instead of radiating in an outward fashion like they appear to us on Earth? This image shows the true nature of crepuscular rays: they really are parallel!

The word crepuscular means “relating to twilight,” and they occur when objects such as mountain peaks or clouds partially shadow the Sun’s rays, when the Sun is low on the horizon. These rays are visible only when the atmosphere contains enough haze or dust particles so that sunlight in unshadowed areas can be scattered toward the observer.

The light rays are actually parallel, but appear to converge to the Sun due to “perspective,” the same visual effect that makes parallel railroad tracks appear to converge in the distance.

In the images taken from the ISS, the sun was setting to the west (image left) on the Indian subcontinent, and cumulonimbus cloud towers provided the shadowing obstructions. The rays are being projected onto a layer of haze below the clouds.

Here’s an image taken by UT reader Stephano De Rosa of crepuscular rays as seen from a more Earthly perspective:

Crepuscular Rays. Credit: Stefano De Rosa

Sources: NASA Earth Observatory, University of Illinois

Nancy Atkinson

Nancy has been with Universe Today since 2004, and has published over 6,000 articles on space exploration, astronomy, science and technology. She is the author of two books: "Eight Years to the Moon: the History of the Apollo Missions," (2019) which shares the stories of 60 engineers and scientists who worked behind the scenes to make landing on the Moon possible; and "Incredible Stories from Space: A Behind-the-Scenes Look at the Missions Changing Our View of the Cosmos" (2016) tells the stories of those who work on NASA's robotic missions to explore the Solar System and beyond. Follow Nancy on Twitter at https://twitter.com/Nancy_A and and Instagram at and https://www.instagram.com/nancyatkinson_ut/

Recent Posts

Juno Reveals a Giant Lava Lake on Io

NASA's Juno spacecraft came within 1,500 km (930 miles) of the surface of Jupiter’s moon…

15 hours ago

What’s the Most Effective Way to Explore our Nearest Stars?

It was 1903 that the Wright brothers made the first successful self-propelled flight. Launching themselves…

22 hours ago

Radiating Exoplanet Discovered in “Perfect Tidal Storm”

Can tidal forces cause an exoplanet’s surface to radiate heat? This is what a recent…

1 day ago

The Giant Planets Migrated Between 60-100 Million Years After the Solar System Formed

Untangling what happened in our Solar System tens or hundreds of millions of years ago…

2 days ago

Artemis Astronauts Will Deploy New Seismometers on the Moon

Back in the 1960s and 1970s, Apollo astronauts set up a collection of lunar seismometers…

3 days ago

Ice Deposits on Ceres Might Only Be a Few Thousand Years Old

The dwarf planet Ceres has some permanently dark craters that hold ice. Astronomers thought the…

3 days ago