꧁༺≣|| Heya , Here is your answer ||≣༻꧂
↓ ↓

↦ The refraction of light caused by the earth’s atmosphere is called atmospheric refraction. The physical conditions of the refracting medium (air) are not stationary.

⇒ Some of the optical phenomena in nature which take place due to the atmospheric refraction of light are as follows:

• TWINKLING OF STARS:
The twinkling of stars is due to the atmospheric refraction of star’s light.

• PLANETS DO NOT TWINKLE:
The planets are much closer to the earth and are thus considered as the collection of infinite point sources of energy.

• THE APPARENT POSITION OF THE STARS IS HIGHER THAN THEIR ACTUAL POSITION:
The apparent position of the stars is higher than their actual position due to the atmospheric refraction. The upper layers of the atmosphere act like a rarer medium whereas the lower layers which are close to the earth acts like a denser medium.

• ADVANCED SUNRISE AND DELAYED SUNSET:
The sun is visible to us about 2 minutes before the actual sunrise and 2 minutes after the actual sunset because of atmospheric refraction. The actual sunrise takes place when the sun is just above the horizon.

• SCATTERING OF LIGHT:
When light falls on tiny particles then diffused reflection takes place and light spreads in all possible direction. This phenomenon is known as scattering of light.

• TYNDALL EFFECT:
The earth’s atmosphere is a heterogeneous mixture of minute particles. These particles include smoke, tiny water droplets, suspended particles of dust and molecules of air.

• DANGER SIGNALS ARE RED
Out of all the colours of visible light, red colour has the longest wavelength. Therefore red colour is least scattered.

♯ S⃠t⃠a⃠y⃠ S⃠a⃠f⃠e⃠ ♯

༉ T̸h̸a̸n̸k̸ Y̸o̸u̸ S̸o̸ M̸u̸c̸h̸ ༊

What is Atmospheric Refraction?
Atmospheric refraction refers to the bending of light as it passes through the Earth's atmosphere. This phenomenon occurs because the atmosphere is made up of layers with varying densities, primarily due to changes in temperature and pressure.
Key Points of Atmospheric Refraction:
- Change in Medium: When light travels from space into the denser atmosphere, it slows down and bends towards the normal line. Conversely, when it exits the atmosphere, it speeds up and bends away from the normal.
- Impact on Visibility: Atmospheric refraction plays a crucial role in how we perceive objects in the sky, particularly celestial bodies. For instance, stars appear higher in the sky than their actual position due to refraction.
- Twinkling of Stars: The twinkling effect observed in stars is a direct result of atmospheric refraction. As light from stars passes through turbulent air layers, it gets bent in different directions, causing the star’s brightness to fluctuate.
Phenomena Related to Atmospheric Refraction:
- Sunrise and Sunset: The sun appears to rise earlier and set later than it actually does due to refraction. The light from the sun bends as it enters the Earth's atmosphere, making it visible even when it is below the horizon.
- Mirage Formation: In hot environments, light bends due to temperature differences in the air layers. This bending creates the illusion of water on the ground, known as a mirage.
- Green Flash: A rare event that occurs just before sunrise or right after sunset, where a green spot is visible above the sun, caused by the atmospheric refraction of light.
In summary, atmospheric refraction is a fascinating optical phenomenon that significantly influences our perception of the sky and celestial objects.