Google trend - Moon halo

A moon halo, also known as a lunar halo or a moon ring, is a fascinating atmospheric phenomenon that occurs when there are ice crystals present in the Earth's atmosphere. It creates a stunning ring of light around the moon, often resembling a halo or a circle.

The formation of a moon halo begins with the presence of high-altitude clouds, typically cirrus clouds, which are composed of tiny ice crystals. These ice crystals can take various shapes, such as hexagonal plates or columns, and they are responsible for the refraction and reflection of light.

When the moonlight passes through these ice crystals, it undergoes a process called refraction. Refraction occurs when light changes direction as it passes from one medium to another, in this case, from the air to the ice crystals. The hexagonal shape of the ice crystals causes the light to bend at a specific angle, typically 22 degrees, resulting in the formation of a halo.

The 22-degree halo is the most common type of moon halo observed. It forms a complete circle around the moon, with the moon situated at its center. The circle is often pale in color and can be quite large, spanning up to 44 degrees in diameter. The size of the halo depends on the size and shape of the ice crystals, as well as their orientation in the atmosphere.

In addition to the 22-degree halo, other types of moon halos can also occur. For example, a 46-degree halo is less common but can be observed under certain atmospheric conditions. This halo is larger and fainter than the 22-degree halo, extending further away from the moon. There can also be other secondary halos, such as a 9-degree halo or a 46-degree halo, which are caused by more complex interactions between light and ice crystals.

Moon halos are often accompanied by other optical phenomena, adding to their beauty and intrigue. One such phenomenon is the presence of lunar corona, which appears as a series of colored rings around the moon. The corona is caused by diffraction, where light waves are bent and scattered by the ice crystals, creating a colorful display.

Moon halos can be observed from various locations around the world, and they are not limited to specific seasons or climates. However, they are more commonly seen in colder regions, where ice crystals are more likely to form in the upper atmosphere. They can occur during any phase of the moon, but they are particularly striking when the moon is full or nearly full, as the brightness of the moon enhances the visibility of the halo.

In conclusion, a moon halo is a captivating atmospheric phenomenon that occurs when moonlight passes through ice crystals in the Earth's atmosphere. The hexagonal shape of the ice crystals causes the light to bend at a specific angle, resulting in the formation of a halo around the moon. Moon halos can be observed worldwide and are often accompanied by other optical phenomena, such as lunar corona. They are a testament to the beauty and complexity of our atmosphere, providing a mesmerizing sight for those lucky enough to witness them.