We are constantly faced with different events that are the result of certain characteristics of our world. For example, its rotation around itself gives us night and day. Thanks to its movement around the sun, we get the seasons. These characteristics also play a role in the clarification of other major events that pose a question mark in the mind.
For example, in this content, we will clarify the case of ‘stars appearing to blink’, which is one of the events in question and which has come to mind at least once for everyone who likes to watch the sky. Without further ado, let’s get straight to the point.
We see that pictures of stars taken through our telescopes in space are very clear.
The reason for this is that there is no obstacle between the light source in space and our telescopes in space, and thus the light reaches its target directly from its source.
So what is changing on earth?
Unlike the above situation, you cannot look directly at the light sources in the sky from the earth as we have just described.
Because unlike him this time, the Earth’s atmosphere enters between you and the light source. So what exactly does the atmosphere do to light?
The term we’re looking for to explain this is astronomical scintillation. Let’s explain simply
As we know, the Earth has an atmosphere with different layers. In addition, the temperature of the air in these layers is not stable.
One layer can usually be warmer or colder than the other, but even these degrees of temperature/coldness are constantly changing within itself.
With the effect of this, the rays that pass through long paths in the endless space are deteriorated in our atmosphere, which is their final destination.
As we mentioned, the temperature of the atmosphere is changing and its movement is constantly continuing.
For this reason, the rays coming from the outside are constantly changing their course on a small scale until they reach our eyes from the outermost part of the atmosphere. In the end, a zigzag-shaped route that changes continuously is obtained.
This situation continues even after the rays reach our eyes.
As a result, sometimes more rays are reflected in our eyes, sometimes less. As more light reaches us, the star that is the source of those rays looks brighter.
Likewise, when the rays are less directed towards our eyes, this brightness decreases. As a result, the stars seem to be winking at us.
When you look at the city lights in the distance, you experience this situation. The reason is the same
In fact, if you look around or slightly above a burning fire, you can still see this phenomenon.
There, too, the constant change in the temperature and movement of the air causes us to see the objects and objects behind us as if they are fluctuating.
Let’s add some interesting information.
- Flickering stars were a nightmare for astronomers at first. Later, with the use of adaptive optics in telescopes, this problem was overcome by following the light movements and more stable images were obtained.
- Planets are closer than stars and therefore appear larger both with the naked eye and with a telescope.
- In this context, if we think of the ray coming from the stars as a point, we do not notice that they vibrate because of the many point rays coming from the planets, which are next to them like a disk rather than a point. This is where the phrase “If it doesn’t vibrate, it’s a planet” originated.
- But everything outside the atmosphere is, to a certain degree, a victim of this degradation.
- Events such as mirages, which are mostly seen in deserts, are caused by the continuous refraction of the light direction by the atmosphere. In this context, a distant object appears as if it is reflecting off the water surface.
This was the reason why the distant star and city lights seemed to flicker. You can share your thoughts in the comment section.
Sources: The Hobart, Neil deGrasse Tyson,