With a lot of advances in the field of sciences, the human race has come a long way from where it started. Today, researchers are not only active in inventing new mechanisms and objects but are also keenly interested in unleashing what is already known to us. Light is one such area. It is one of the phenomenon that we witness in our everyday lives but don’t really talk much about. Major discoveries have shaped our assumptions about it. But we always have that little something that still needs to be addressed and researched.
Here’s a list of the top 10 facts about light every one should know!
- We can see objects only when light enters the eye
Well, this one doesn’t really come as a shock to many. So here it is. People and many other creatures can only see objects when light enters their eyes, which is a fact everyone must know! The way our body works is very important in making us see the world around us. There are two known ways through which light enters our eyes are: number one is directly through a light source and the other one is reflected light. This further explains and justifies the reason why we only see black with our eyes closed!
2. Scientists weigh stars using light
Did you know the extended features of light? Apart from all it has done for us, light is even used by scientists to weigh stars. While looking through a telescope, a star’s observed position might as well be different from its real position. It is because the reason that when the light comes a bit too close to an enormous star, the star’s gravity bends it. Furthermore, using Albert Einstein’s Theory of relativity, scientists have even predicted the weight of stars because a massive star can easily curve space-time. In order to study a white dwarf star, scientists practically used this concept in 2017.
3. Light is an electromagnetic wave
Light is nothing but a wave. Well, indeed it is. But it is not just any wave, it’s an electromagnetic wave. This means that it is a wave that is created as an outcome of vibrations between an electric as well as a magnetic field. This, simply means that the light waves are made up of the oscillation between the electric and magnetic fields. Thus, in the case of light, it doesn’t necessarily need a medium to travel from one place to another. Other examples of electromagnetic waves include x-rays, radio waves, UV rays, microwaves, and many others.
4. Every object produces light
Light is not only produced by the objects that emit it but by every possible item, you could think of. Yes, it is not just a saying but a fact that every object produces light! Be it your bag, vegetables, clothes, or whatsoever, literally, everything has light. Coming to the possible reason for this…by now we already know that light is the primary reason that we are able to see objects. Right? Yes. And how exactly do we see an object? Possibly because it either produces light or reflects it. Thus, reflection is the name of the game. It makes things looking lit to our eyes.
5. Sonoluminescence- Bubbles can turn sound into light
As difficult as it is to pronounce the mechanism’s name, it is really simple to understand. Sonoluminescence is a technique that makes a bubble turn sound into light. The ultrasonic sound waves that are generated in a pool of water, further lead to the production of little bubbles, which eventually emit a tiny bit of light. Sonoluminescence was first uncovered in the year 1934 but didn’t really provide any clarity as to how it works. Today, scientists are devoted to developing several hypotheses while practically conducting experiments to find out the exact process.
6. The beautiful Auroras are a result of solar wind
Have you ever given a thought to the reason that makes the auroras a beauty of its own? Well, here is another must-know fact about light and its many functions. Solar winds generated from cosmic events including solar flares, interact with oxygen particles on reaching the earth’s surface. This causes them to emit what we call The Aurora Borealis (in the north) and The Aurora Australis (in the south). They are those stunning bluish-green lights that can only be witnessed in some parts of the earth. They are also believed to emit atmospheric nitrogen atoms.
7. Lasers can identify malaria
A fast-acting disease that even has the ability to kill people within hours if not acted upon immediately, Malaria can be detected using light. Although it can be detected using other traditional methods, lasers are believed to the fastest of them all. Usually, when the malaria-causing parasite enters a healthy human body, they tend to change the course of the red blood cells. When doctors figure out a change in the cell structure, they can immediately tell if the person is malaria-infected or not! And this laser light device that can microscopically point out malaria has an accuracy level of 85%.
8. The speed of light can be manipulated
Light is incredible and so are its properties. It can travel in a vacuum with a speed of around 3 x 10⁸ m/s, which is over 1 billion km/hr. However, the light speed can sometimes be manipulated! The infamous Bose-Einstein Condensates are believed to be its speed breakers. This is due to the reason that these condensates have the ability to store light waves, making them temporarily slow down. They have some super cool states of matter with almost no energy, where they begin to be in a quantum state.
9. The laser cooling technique
We probably know that atoms are sometimes heated to perform several processes, but cooling them is another technique that has some cool benefits of its own. Usually, when a ray of light hits an atom traveling in an opposite direction, its velocity is decreased. This process cools down the atom. Invented in 1985, the laser cooling technique is also referred to as Doppler Cooling. It makes the atoms cold after pointing a laser at a comparatively lower frequency, which altogether reduces the atom’s velocity. This is majorly related to the Bose-Einstein Condensates.
10. Bright light causes some people to sneeze
This one’s probably kept unknown to many. Bright light, including sunlight, has the ability to make some people sneeze in its presence. Moreover, it is believed that around 18% of the human population is actually affected by this sneezing problem. It is known as the photic sneeze reflex. Although researchers have observed the mechanism, they still are not quite sure about the reason behind it. Maybe it’s a cranial nerve that is responsible for some facial sensation, or it’s just about the optic nerve situated in its close proximity.