Posted in Science & Nature

Shooting Star

When an object from outer space enters the Earth’s atmosphere, it starts to burn up and creates a brilliant streak in the sky, which we call a meteor or shooting star. Contrary to popular belief, this is not due to friction with the air in the atmosphere.

An object entering the atmosphere is typically travelling at extraordinary speeds. Most meteors are travelling around 20km/s (or 72000km/h) when they hit the atmosphere. At these speeds, air molecules do not have a chance to move out of the way. The meteor will instead collide into the air molecules, pushing them closer and closer to each other, compressing the air in front of it.

As we know from physics class, compression increases temperature in gases as per the ideal gas law (PV=nRT). The impressive entry speed of these meteors result in so much air compression that their surface can heat up to 1650 degrees Celsius.

The heat boils and breaks apart the contents of the meteor, turning it into superheated plasma that gives off a glow. This is the streak of light that we see in the night sky when we wish upon a shooting star.

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Posted in Science & Nature

Constellation

To our ancestors, the night sky was not only useful for navigation and telling the seasons, but also for entertainment. Using the mind’s eye, they connected the dots to form a skeleton of a picture – a constellation.

Constellations became the basis of numerous tales and legends. The ancient Greeks told stories of mighty hunters fleeing from scorpions, of fair maidens chased by satyrs, and of noble animals who helped a hero in their quest. In the Far East, they tell a story of lovers who are punished by being placed on separate stars, only being allowed to meet once a year. Similar stories based on constellations can be found in almost every culture around the world.

Constellations are fascinating as they just look like a collection of bright dots to us, but in reality, they represent a spread of stars throughout the cosmos, unimaginably far from us and each other. Even though the stars may appear to be right next to each other, one star may be thousands or millions of light-years further from us than the other.

This is because a constellation is a two-dimensional picture representing three-dimensional space, meaning that depth is ignored. Because of the great distance, entire worlds appear to be simple points, while the vast emptiness of space flatten out to short gaps.

Mythologies and stories based on constellations teach us many pearls of wisdom, but perhaps this is the most valuable lesson the constellations have to teach us. When we look at something from a distance, we lose the fine details. Even the awe-inspiring beauty and size of the cosmos can be reduced down to a simple line drawing in the sky.

The same principle applies to people.
When we judge a person, we reduce a complex life full of stories, experiences, thoughts, feelings and circumstances down to a single stereotype, letting us objectify, criticise, belittle and dismiss people easily.
When we comment on a historical event, we focus only on big events and try to simplify the narrative to a few cause-and-effect stories, while conveniently forgetting the individual lives affected or the broader context that led up to that point.
When something bad happens in the world, we try to find meaning or something to blame, instead of trying to understand the numerous variables that factor into the situation.

Constellations are beautiful, but they don’t tell the full picture. If we want to truly understand the world we live in and the people we share that world with, we have to learn to consider the details and look at things from different points of view.

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Posted in History & Literature

Zodiac: Gemini

Gemini is the Zodiac sign for those born between May 21 and June 21. The symbol for Gemini is a pair of twin boys.

The model for Gemini is the twin sons of the Spartan queen, Leda – Pollux and Castor. The two, despite being twins, have different fathers, with a peculiar back-story. Zeus was in love with the beautiful queen Leda, so he transformed into a swan to seduce her. They made love, making Leda pregnant with Zeus’ son. However, she also slept with her husband the same night, leading to her being pregnant with another son. Thus, Pollux was born an immortal demigod with the blood of Zeus, while Castor was born a mere human. Despite this, the two had exceptional brotherly love for each other and would do everything together. Pollux possessed great physical strength, while Castor possessed great ingenuity. But one day, Castor died from a fight, causing great despair for Pollux. No matter how hard he tried, he could not kill himself due to his immortality. He cried out to Zeus: “If I cannot be with my brother, then I do not want to be immortal”. Zeus, taking pity on the two and admiring their love for each other, offered to halve Pollux’s immortality and share it with Castor. This is how they became a bright constellation in the night sky, side-by-side.

(Part of the Zodiac series: https://jineralknowledge.com/tag/zodiacs/?order=asc)

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Posted in Psychology & Medicine

Time Perception

What exactly is the present? The present is the middle point between the past and future, the world that we experience and perceive on a real-time basis. But would you believe it if the world you perceive is not the true “present”? To experience the world, we use our five senses. The brain collates all these sensory information and processes it to construct “the present”. This process takes about 80 milliseconds. Ergo, the world we experience is actually the world as it was 80 milliseconds ago. For a similar phenomenon, consider the stars. The stars we observe are not what they look like now, but what the stars looked liked when they emitted the light that we see. Thus, the star you are looking at may not even exist anymore.

But 80 milliseconds is a very short time; surely it has no impact on our everyday life? To prove that this delay has a critical impact on our understanding of cause and effect, neuroscientists designed the following experiment. The researchers would ask the participant to press a button that caused a light to blink after a short delay. After about ten tries, the participants reported that the delay had disappeared and the light flashed immediately after they pressed the button. This was due to their brain editing out the time delay and directly connecting the cause (button) and the effect (flash). But a much more peculiar phenomenon was seen when the researches removed the delay between the button press and the flash. Participants reported that they saw the light flash before they even pressed the button. The participant’s brain had become so used to the editing process that it was confusing the order of the cause and the effect.

The brain’s time-editing ability can be seen in the following simple experiment. If you touch your nose and toe at the same time, logic dictates that as the toe is further from your brain, the signal will have to travel further and it will be felt later. But in reality, you feel both at the exact same time. This is because your brain uses a map of the body to edit the relative time the signal takes to reach the brain to better construct a “real-time present”.

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