paraxial image

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Middle East bee locator map

Are the Middle East and the Near East the Same Thing?

An ancient egyptian hieroglyphic painted carving showing the falcon headed god Horus seated on a throne and holding a golden fly whisk. Before him are the Pharoah Seti and the goddess Isis. Interior wall of the temple to Osiris at Abydos, Egypt.

11 Egyptian Gods and Goddesses

Close up of praying mantis walking on stone ground against a blurred background in Japan

6 Animals That Eat Their Mates

Dancers at a Cinco de Mayo festival at the Mission District, San Francisco, California. (Photo dated 2019.) holidays

Is Cinco de Mayo Mexico's Independence Day?

Artist interpretation of space asteroids impacting earth and moon. Meteoroids, meteor impact, end of the world, danger, destruction, dinosaur extinct, Judgement Day, Doomsday Predictions, comet

Major Mass Extinctions

Lake Mead (the impounded Colorado River) at the Hoover Dam. The light-coloured band of rock above the shoreline shows the decrease in water level in the first few years of the 21st century.

6 Lakes That Are Drying Up

Demystified - Do Lemmings Really Commit Mass Suicide? illustration

Do Lemmings Really Commit Mass Suicide?

paraxial image

optics

Learn about this topic in these articles:

optical ray-tracing

In optics: Paraxial, or first-order, imagery
In a lens that has spherical aberration, the various rays from an axial object point will in general intersect the lens axis at different points after emerging into the image space. By tracing several rays entering the lens at different heights…
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