Boxing Science and Cosmic Fights
Inspired by the artistic reproductions of the first pictures from the James Webb Space Telescope, the astrophysicist Mia guides Leo, Ren and Zoe across a unique training unveiling the forces behind terrestrial and space phenomena.
A few weeks ago the world had the privilege to look at the deep Cosmos and its undeniable beauty. Bright sources in the sky have been touching humans’ souls, still inspire poets and philosophers and challenge scientists looking for something beyond their comfort zone of knowledge.
The Stephan’s Quintet is the main subject of one of those first mesmerising pictures that JWST gifted us with. A postcard from the Cosmos showing a group of galaxies in the Constellation of Pegasus, a few hundred light years from Earth.
Stop Motion in a Fairy Tale of Destruction
What makes this picture so important is that it clearly shows the dynamical interactions between galaxies. And makes a stop motion in their secular evolutionary path.
☍ We are used to think about galaxies as ensembles of stars with an ordered structure: either elliptical or spirals. But they are like human beings: their appearance changes in time.
☍ Elliptical and spiral morphologies are just the final body galaxies reach in their adult-life. They are the result of multiple interactions with other galaxies, and each encounter makes them either a bit or dramatically different from before.
✅ Why those encounters take place? Because each galaxy has a mass, and so a gravitational field. The latter is the name physicists use to refer to the influence that a certain massive object can either exert on surrounding massive objects or feels from them.
✅ Why are those encounters so crucial for Galaxy Evolution? Because when two or more galaxies gravitationally affect each other, they produce forces acting on each other. Such interactions can disturb and change their morphologies.
In the Stephan’s Quintet the interactions are clearly visible through the tidal tales extended well beyond the body of the galaxies.
Another famous encounter
When the subject of interest is galaxy interaction, there is another, more famous example of this violent yet informative phenomenon: the Antennae Galaxy.
Characterised by a unique hearth-shape, the Antennae is formed by two merging galaxies with approximately equal mass. The outcome is the formation of one single galaxy with tidal tails and a peculiar morphology, and home for bursting star clusters!
A Cosmic Fight
To summarise our learning so far, we can say that galaxies interact like in a boxing match governed by the gravitational force.
This force, driver of monstrous cosmological phenomena, is actually something familiar to us. It is the force binding together our solar system, and on our planet we know it as the force acting on falling objects.
And we enter this picture, too! Since have mass, like galaxies, we generate a gravitational field!
Just a (lot!) little smaller.
This means that when we move, we are able to carry a force depending from our mass and from how fast we are moving.
For example, when we play soccer or volleyball, we we hit the ball exerting a force using and moving our body.
Having this piece of knowledge, we can now link the cosmic fights mentioned above to… boxing science!
Boxing Science
Boxing is like a problem-solving activity. You study your opponent and with for their error to counterattack.
🥊 However, you also need to learn how to move your body to maximise the impact of punches and minimise the damage when being hit!
🎯 We can fulfil these goals training our body and mind, so that we can use our mass and speed to become better fighters.
Impulse and Momentum
As we said earlier, we have mass. While moving at a certain speed, we can carry an amount of motion named momentum: m = mv.
✅ To change it, we need to vary our motion.
✅ What is the cause of motion? The Force!
✅ It is possible to vary our momentum by exerting a force in a certain amount of time. This quantity is called impulse: Ft.
So we can write the following relation: Ft = mv.
The impulse is a very important concept that we experience in our daily life. And we can learn about it in an intuitive way.
✅ Let’s make an example. Impulse is a force exerted in a certain amount of time. Let’s choose a long time interval and just an instant. The same force will be more effective if released in a blink of an eye than prolonged in time.
Let’s visualise an example in the pictures below. A truck can be stopped by an haystack without any damage. Also a wall can stop it, but in a destructive way, because the force the wall opposes to the truck goes through a sudden release.
From the example above is clear that time is key to reduce the impulsive effect of the force. The same concept applies when we need to defend ourself in a boxing match.
Exactly! In a boxing match:
✅ If you wait from the punch or you move towards it, you will receive its full force in an instant of time;
✅ If you move away from the punch, you will receive it in a prolonged time interval, making your opponent’s effort much less effective!
We can do better using hip-rotation!
Given the formula Ft = mv, we notice that the faster we move, the higher is the chance to land an effective jab.
But there is something else we can do.
We can involve more mass in the punch!
✅ We just need to throw our front-jab using not only our arm and shoulder, but the whole body!
By doing hip-rotation, we activate a kinetic chain where we use the full mass of our body. Let’s make an example.
Mia’s friend, Zoe, can throw a front-jab accelerating her arm up to 3.5 m/s².
✅ What is the force she produces using only her fist?
✅ And how much does the force change is she adds hip-rotation?
Let’s answer these questions applying the formula for the Newton’s Law of Dynamics, where any force is quantified in terms of the product between the mass and the acceleration: F = ma.
✅ In the first case (no hip rotation) Zoe uses only her arm, which weights 5 kg. So the exerted force is: F = 5 kg ⋅ 3.5 m/s² = 15.5 N, where N means Newton and is the unit for the force.
✅ Adding hip-rotation, Zoe uses her whole body, so she moves 55 kg. The force is F = 55 kg ⋅ 3.5 m/s² = 193.5 N, that is 11 times more!
With the simple of of adding hip-rotation, we can punch more than 10 times harder!
And what about shadow boxing?
Shadow boxing is a very good cardio training for the whole body, and the reason is because more energy is expended in missing a punch than landing a punch!
When you land a punch on your opponent during a match or on your punching bag, they stop it, exerting the same force you throw at them, but in the opposite direction.
Such dynamics describe the Third Principle of Dynamics, the principle of Action and Reaction. Each action is counterbalanced by an equal and opposite reaction.
When you miss a punch nobody is there to receive it… you need to stop it!
The take-home message is…
Physics is that nerd and mathy discipline studying the laws of nature and the phenomena governed by them. And those laws we observe in the Universe, in an infinite, mysterious cosmic lands… we find them here on Earth, at school, at home, at the gym.
✨ We are stardust and still connected with the Universe.
✨ Fight with a strong body and a smart mind.
✨And remember: the stars are not so far away!
Thank you for reading!
AstroFederica
💫 Text and comics by AstroFederica. Discover more on Social Media, Patreon and Webtoon: https://linktr.ee/astrofederica .
