1. Diamond dust consists of very small ice crystals that form at sufficient humidity and extremely low temperature (below −30°C). In the sun, the ice crystals in the air sparkle better than diamonds, hence the name.
2. Sunset is a colorful optical phenomenon produced by the rays of the setting sun that have to go through a thicker layer of the atmosphere. As a result, we see more of the red light instead of the blue light.
3. Crepuscular rays are a phenomenon that occurs at sunrise or sunset, when sunlight is scattered by clouds, forming narrow beams.
4. Polar stratospheric clouds are similar to cirrus clouds in terms of shape and get an iridescent glow when the sun is a few degrees below the horizon.
5. Dew is very small droplets of water that form in calm weather due to air cooling. They gradually merge and become larger on the grass and leaves.
6. Frosty patterns are the result of water vapor crystallization when the temperature of the surface drops below 0°C (they are usually found on window panes in winter). The pattern depends on temperature and humidity.
7. Rainbow is an optical phenomenon in the atmosphere caused by the processes of refraction, reflection and diffraction of light in water droplets.
8. Snowflakes are hexagonal ice crystals falling out of clouds. Every snowflake is unique because they collide, stick together, attract supercooled droplets, and are constantly changing.
9. Heart-shaped clouds. Clouds can have almost any shape. Sometimes they inspire familiar images and can look like a heart.
10. Halo is an optical phenomenon that appears around the Sun or Moon. It is caused by refraction and reflection of light in ice crystals.