The Science of Sunsets:
Did you know that migrating birds
use sunsets to keep on course?

unsets are a lot more than just bright colors painted in the clouds. Did you ever wonder how they are created? Or what other uses in Mother Nature's plans they fulfill?

Let's first take a look at how sunsets are created. You've no-doubt seen a prism and how the sun's light is split into the colors of the spectrum.

A sunset is created based on the same principles. As the sun sets on to the horizon, the angle of light changes and any particulate matter in the atmosphere (dust, pollution, moisture, etc.) contributes to refracting the rays of light as they enter the atmosphere.

The various angles of reflection offered by varying sky and air quality conditions refract the sun's light just like a prism serving up the array of colors we see as the sun's rays pass through the atmosphere.

Since no day's conditions ever are identical, each sunset is an original work by the chief artist herself -- Mother Nature!

As with everything in nature, scientists are finding that sunsets have an important role in the workings of our natural universe. Recent studies have discovered that migrating birds use sunsets for navigational purposes to stay on their migratory path.

U.S. and German researchers made the connection between the effects of the setting sun and on-bird navigation systems while investigating how the winged creatures avoid getting lost when crossing the equator at night.

Scientists already knew that birds, just like ancient mariners, use stars, the sun and the earth's magnetic field to keep on course, but the latest research published in the journal, Science, indicates that birds take cues from sunsets to reset their internal compasses on a daily basis.

The research team made their findings by studying free-flying birds that were caught and outfitted with tiny radio transmitters. The scientists put some of the birds in an artificial magnetic field to confuse them, then released them.

Following the birds by car for up to 1,100 kilometers, the team found that the birds confused by the artificial magnetic field flew west, while the group not tricked by the artificial magnetic field flew north as usual.

The next day, after seeing the sun, all birds flew north, which lead the scientists to conclude that birds use twilight cues to re-calibrate their internal compasses on a daily basis.