Organic Molecules Discovered On Saturn's Moon

Discovery of Organic Molecules

Scientists recently confirmed the presence of complex organic molecules in the icy plumes of Enceladus, the sixth largest moon of Saturn. These molecules, some of which are considered precursors to amino acids, the harbingers of life, were detected in ice particles ejected from fissures near the moon’s south pole. This suggests that the moon has the chemical ingredients necessary to support intelligent life.

Why Organic Molecules Support Life

Organic molecules are compounds primarily made of carbon, hydrogen, oxygen, and nitrogen, forming the building blocks of life, such as amino acids, sugars, and lipids. Their presence is crucial because they are the raw materials from which living organisms construct cells, proteins, and DNA. Without organic molecules, life as we know it cannot exist.

How Astronomers Found the Molecules

Astronomers analyzed data collected by the Cassini spacecraft, which flew directly through Enceladus’s geysers. Using onboard instruments, scientists examined the composition of ice grains and vapor, detecting carbon-rich molecules to their surprise. By studying the freshly ejected particles, they ensured that the molecules came from Enceladus’s subsurface ocean rather than being altered by space radiation.

The Cassini spacecraft, launched in 1997 as a joint mission by NASA, ESA, and the Italian Space Agency, spent 13 years exploring Saturn and its moons, studying the planet’s rings, atmosphere, and magnetic field. This discovery by Cassini is a huge success towards finding places in our own solar system which can support extraterrestrial life.

About Enceladus and Its Relation to Saturn

Enceladus is a small, icy moon orbiting Saturn and is famous for its bright, reflective surface. Compared to our Moon, diameter ~3500 km, Enceladus measures small, about only 500 kilometers in diameter and harbors a hidden ocean beneath its icy crust. The moon shoots geysers of water vapor and ice into space, which were studied by scientists through Cassini spacecraft. Enceladus’s relation to Saturn is not just orbital... its geysers feed particles into Saturn’s ring system.

What Scientists Have Said

Scientists have expressed excitement about the findings. One researcher noted, “These organic molecules are some of the freshest we’ve seen in the solar system, and they likely originate from Enceladus’s hidden ocean.” Another added, “Discoveries like this bring us closer to understanding whether life could exist beyond Earth.” 

Existence of Extraterrestrial Life

For life to exist beyond Earth, astronomers believe three main ingredients are necessary: liquid water, organic molecules, and a source of energy. Enceladus has all three, thanks to its subsurface ocean, detected organics, and heat from tidal forces. Scientists emphasize that while this doesn’t prove life exists, it makes Enceladus a prime candidate for habitability studies.

How Gold, Platinum And Uranium Formed?

The most remarkable discovery in all of astronomy is that the stars are made of atoms of the same kind as those on the earth: Richard Feynman.

Water makes up nearly 70% of human body by weight. The components - hydrogen is the most abundant element in the universe and oxygen was forged in the interiors of collapsing stars. While the body is this or that many years old the components are nearly as old as the universe itself!

The first atoms were made approximately 380,000 years after the big bang. Prior to this, the universe was a hot soup of ions and subatomic particles. But as the universe continually expanded, it became less dense and colder allowing the simple atoms of Hydrogen.

Humongous clouds of hydrogen were clumped together under the force of gravity and ancient stars began shaping up. Just like a cotton candy is spun from sugar solution, a star is spun from an uncountable number of Hydrogen atoms. How does a star continually burn? Its source of energy is nuclear - by converting Hydrogen to heavier elements, like Helium - the second most abundant element in the universe.

At the end of a star's life, its main fuel Hydrogen ran out and Helium is converted to further heavier elements like Oxygen and Carbon - building blocks of life. Thus, we can say that we are the children of stars. It is a profound realization that only few can truly appreciate. We are made of star stuff, said astronomer Carl Sagan. The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of dying stars.

In the same capacity, physicist Lawrence M Krauss said - Every atom in your body came from a star that exploded. And, the atoms in your left hand probably came from a different star than your right hand. It really is the most poetic thing I know about physics: You are all stardust. 

Question is, where do rare elements like Gold, Platinum come from?

The answer is rare occurrences - supernova and neutron star mergers. That's what makes these elements so precious! An ordinary star, like our sun, will die a slow death by becoming a white dwarf first and it will gradually cool to a black dwarf.

On the contrary, stars which are 8 times heavier than the Sun will explode in a supernova, flinging debris miles around, destroying themself, leaving behind a crushed reactor core (a neutron star or black hole). Some heavy elements like iron, nickel, and a bit of gold/platinum can be formed during the core-collapse phase of a Type II supernova.

Even heavier elements - Uranium, which is extremely rare, is formed by the merger of neutron stars, a scarce event called kilonova. Also, most of the gold and platinum in the universe are forged during violent neutron star mergers, where extreme gravity and neutron-rich environments trigger rapid nucleosynthesis — in fact, a single merger can produce hundreds of Earth-masses worth of gold.

This was confirmed in 2017 with the gravitational wave event GW170817, when astronomers observed a neutron star merger producing huge amounts of gold and platinum!

And now the data from the James Webb Space Telescope is helping astronomers identify the infrared signatures of freshly formed gold and platinum in distant kilonovae, offering real-time evidence of heavy metal birth in the early universe.

Summing up, everything we are made of, and whatever we have here on Earth, all life, magic and rare wonder, has come straight from the star factories. We are the universe. We are the successor of starry nights, catastrophic explosions and violent mergers.

7 Myths People Have About Quantum Physics

1. Quantum physics means everything is random

While uncertainty principle by Werner Heisenberg plays a key role in the field of quantum mechanics, the ability to predict other aspects of the atomic world, and that too with a great degree of accuracy is astounding. In other words, the quantum world is chaotic, mostly probabilistic, but not entirely driven by chance.

2. Quantum physics cannot be visualized

American physicist Richard Feynman once said, "Nobody understands quantum mechanics." The reason being, quantum physics is swamped by complex mathematical systems that very select people can comprehend. However, there are ways to visualize the mechanics of quantum world, like the wave function, and even Feynman diagrams are used to visualize the behavior of interacting subatomic particles.

3. Quantum physics supports mysticism

The spooky principles of quantum physics are often exaggerated by media and cause people to make wild claims. Due to a mix of misunderstanding and lack of evidence, people see quantum mechanics as a source of great spiritual and physical mystery. On the contrary, quantum mechanics is among the most well studied, predictable and accurate piece of sciences, and partly responsible for amazing technologies like the microprocessor on your cell phone, LASER, etc. The right thing to say would be, quantum physics supports modern and future technologies.

4. Quantum physics can explain everything in the universe

Some people think that quantum physics is the new golden religion. That quantum physics has answers to the origin of the universe, consciousness, life and God. Truth is, no one has answers to these big questions. The word "quantum" means "small", and quantum mechanics is a system of governing principles in the world of atoms, molecules and elementary particles. There are metaphysical regions beyond the empirical scope of quantum physics. So no, quantum mechanics cannot explain everything.

5. Particles can exist in two places at once

The square of the wave function's magnitude gives the probability of finding the particle in a specific location. While it is numerically true, that the wave function is spread over space, meaning, the particle could be at several places at one time. But in the end, this is not literal truth. Wave function is only a mathematical device, a number, or probability. Ultimately, the particle exists at only one location, we do not know which for sure. When measured (e.g., detected at a specific position), the wavefunction “collapses” to  that one state.

6. Einstein was an enemy of quantum physics

Not really. Albert Einstein used the quantum model of energy, as proposed by Max Planck, to explain the photoelectric effect, which is a phenomenon used in modern day solar panels. In fact, Einstein was awarded the Nobel Prize in physics for this very groundbreaking work. Nowadays, people generally quote Einstein's famous saying - "God does not play dice." The quote is nothing more than a reflection of Einstein's discomfort with quantum mechanics. Because in classical Newtonian mechanics, which everyone got attached to, everything was determined, and predictable. But in the atomic scales, which are beyond our imagination, predictability is our enemy. Randomness rules, because of Heisenberg's glorious uncertainty principle.

7. Particles switch between wave and particle nature

Actually, the microscopic world is so bizarre that we need pictures of macroscopic world, a ball (particle) or a ripple in water (wave), to comprehend what's really going on. Feynman quipped - "Electrons act like waves.. No they don't exactly. Electrons act like particles... No they don't exactly." It is a myth that subatomic particles morph back and forth between wave particle duality. But the electrons, protons, neutrons and other such "things" are neither particles nor waves. The particle and wave models are used by us because our human brain can think easily in that regard.

10 Unknown Facts About Physicist Max Born

Max Born (1882 - 1970) was a German British physicist and mathematician who was one of the pioneers in quantum mechanics. Born was also a great teacher and was doctoral advisor to physicists like Robert Oppenheimer and Maria Goeppert Mayer.

Born's work involving wave function is cool because it shows how the universe can be unpredictable and mysterious at its smallest scales, yet we can still make sense of it with mathematics. Born rule opened the door to discoveries that power modern gadgets like laser, LED and microprocessors.

10 hidden facts about Max Born

⚛️ 1. Max Born started his academic journey with mathematics. He was more interested in abstract mathematical ideas than physics. However, this changed when the quantum revolution began in Europe and Max went on to work on wave function, a key element in quantum physics.

🎓 2. Max Born was classmates with Albert Einstein's future wife and mathematician, Mileva Maric, who is said to have collaborated with Einstein on special relativity. Born and Mileva studied together at ETH Zurich.

💡 3. Max Born co-invented matrix mechanics with physicist Werner Heisenberg, but rarely gets credit for his work. Born was the first to realize the mathematics involved was non commutative matrices.

🏆 4. Max Born won the Nobel prize in 1954, for work he did in 1920s. It took nearly 25 years for the scientific community to recognize Born rule, which provides the probability of finding a particle in a specific state when a measurement is made.

Born is second from the right in the second row, between Louis de Broglie and Niels Bohr.

✈️ 5. Being a Jewish, Max Born fled Nazi Germany as he was politically vocal against the government. He escaped to Cambridge, with only one suitcase.

🎵 6. Born was a talented painter and musically gifted. He used to collab with other scientists including Albert Einstein. They played sonatas together, Einstein on violin and Born on piano.

📜 7. Born wrote letters to Einstein challenging determinism. He defended quantum indeterminacy, while Einstein famously replied, “God does not play dice with the universe.”

☮️ 8. Max Born was a strong advocate of peaceful use of science. After world war 2, he became a critic of nuclear weapons and signed Russel Einstein manifesto aiming for global disarmament.

🧳 9. Born never returned to Germany even after the second world war was over. He became a British citizen and chose to stay in the UK.

🧬 10. Musical genius ran in the family as Max Born's granddaughter is British Australian singer Olivia Newton-John, who sold over 100 million records.

5 quotes of Max Born

🔬 1. I am now convinced that theoretical physics is actually philosophy.

🧪 2. In science, we are in a jungle and find our way by trial and error, building our road behind us as we proceed.

🌍 3. The belief that there is only one truth and that oneself is in possession of it, seems to me the deepest root of all that is evil in the world.

🪐 4. Science is not only the basis of technology but also the material for a sound philosophy.

🧠 5. Physics as we know it will be over in six months.

Politicians Should Listen To Carl Sagan FAST!

Carl Sagan was an American astronomer who actively campaigned against nuclear weapons and pointed out the potential dangers, like a nuclear winter. Given that Israel and Iran are at war, while Russia and Ukraine have been going at it since years now, it is important for politicians to set aside their egos and read this wonderful, humanizing speech by Carl Sagan.

Background

The Pale Blue Dot is an image that was taken by NASA at Carl Sagan’s suggestion. The astonishing picture came from Voyager 1, a spacecraft launched in 1977 to study the outer solar system. When Voyager was about to exit the solar system, it turned around one last time to take a farewell photo. Earth appears as a very small stage in a vast cosmic arena, Sagan quipped.

The picture is evidence enough of our tininess in the universe. The enormity of space cannot be comprehended from our comfortable air conditioned rooms, but when you look at a picture like Pale blue dot, something moves you from the inside. That yearning to find our place in the Cosmos and persistent urge to "make it big" in Earth lingo, are challenged by this point of pale light.

Significance

Sagan used this image to challenge arrogance and nationalism. He pointed out that there is no hope that help will come from elsewhere to save us from ourselves. We have to protect our fragile planet, which is the only place we know of in the universe that supports life in all its glory.

In gaming terms, Earth is a checkpoint, a reminder that life happened here. The problem is, our intelligence has become quite dangerous in modern times. Blinded by power and ego. Therefore, politicians must find a few seconds from their busy schedules and take a look at Pale blue dot.

According to Carl Sagan, astronomy is a humbling experience and presents a possibility of peace. When we recognize how small our disputes look from the perspective of the universe and that earth is the only home we will ever know we will cherish it more perhaps. Sagan once said: "If a human disagrees with you, let him live. In a hundred billion galaxies, you will not find another."

Technicals

Pale blue dot was taken in February, 1990 from a staggering distance of 6 billion km. Of the 640,000 individual pixels in the image, Earth appears as a tiny pixel suspended in a ray of sunlight. A narrow angle camera aboard Voyager 1 was used to capture Earth's location. Earth looks blue in the photograph primarily because of Rayleigh scattering of sunlight in its atmosphere.

Excerpt

Here is a small excerpt from pale blue dot speech by Carl Sagan which every politician should read: The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot.

There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known.

Where Are Wormholes: Shortcuts In Space?

Just like there are clever shortcuts on Earth to beat the traffic, what if there were "shortcuts in space" to bypass the enormous distances in the universe? That’s basically what a wormhole is - a theoretical tunnel through space and time.

Wormhole history

Technically, a wormhole is called Einstein-Rosen bridge.

The concept began with Albert Einstein and Nathan Rosen in 1935. They discovered that theory of general relativity made strange structures to link distant places in the universe possible. The term wormhole for such a structure was coined by physicist John Wheeler in the 1950s.

Physicists were fascinated. Wormholes soon became a favorite tool in science fiction. But the only problem with Einstein-Rosen bridge or wormhole is that the kind of wormhole described by Einstein and Rosen equations would collapse too soon for anything to pass through.

Picturing wormhole

Imagine space as a giant flat sheet of paper. If you draw two dots on opposite sides, the shortest way to connect them is a straight line, right? But what if you could fold the paper in half so the dots touched? Now you can connect the dots instantly - no long journey needed. That’s the basic idea behind a wormhole.

Wormhole literally

Now the wild thing is wormholes do not just connect space. They are also portals in time. If one end of a wormhole moves faster than the other, time would pass differently at each end. Therefore it is theoretically possible to use wormhole for time travel.

Math of wormhole

The math behind wormholes comes from Einstein’s field equations, which describe how mass and energy shape space and time. Massive objects bend space and time — like a bowling ball on a trampoline. If space can bend, maybe it can also fold too — bringing two distant points closer.

When scientists solve Einstein's equations under special conditions, wormholes are one possible result. Most solutions show wormholes collapsing before anything can use them. To keep wormhole open for long time, we need to create matter with negative energy, which is not quite possible.

Wormhole in media

Writers are fascinated by wormholes as they allow characters to hop across galaxies in seconds, which keeps stories moving without spending 1,000 years in a spaceship. Shows like "Dark" and "Doctor Who" have made use of wormholes in their plot.

Movies like Interstellar, Contact and Thor use wormholes in their storylines. Interstellar uses a scientifically inspired wormhole near Saturn to allow humans to explore other galaxies. In Contact, an alien-built machine creates a wormhole for interstellar communication and travel.

Do wormholes exist?

Have we ever discovered a wormhole, like we discovered a black hole? Math allows wormhole existence but astronomers have yet to identify one. Some scientists believe that wormholes might be hidden inside black holes. Others say they probably don’t exist at all.

Wormholes sit at the intersection of science and imagination. Wormholes offer a hopeful vision of overcoming the vastness of space — or even time. Whether practical or not, wormholes inspire stories, dreams, and real scientific questions.

Who knows? Maybe someday, wormholes will go from sci-fi fantasy to part of our cosmic travel plans. Until then we will have to thank Einstein and Rosen for empowering our writers community.

10 Fantastic Ways In Which Snails Use Physics

Nowadays, courtesy of early monsoon in Delhi, snails big and small, fast and slow, greeted the lawns of India Habitat Center one evening. In some cultures, observation of snails in abundance represents slow but steady progress and good luck. Furthermore, snails are also bio monitors and indicate the quality of environment - temperature, pollution, etc.

What I was more fascinated by was the physics of a snail. How snail was defying gravity and climbing up the wall without second thoughts. How the mucus left behind by Snail's muscular foot must have helped it reduce friction, but also slowed it down and so on.

It was a magical day to say the least and more than a dozen snails showing up was no less than a happy serendipity. Snails might seem simple, but they rely on a surprising range of physical principles in their everyday life. Following are 10 ways in which a snail uses physics for its survival:

1. Surface tension: Snails secrete a mucus to create a slimy track. Because of surface tension, the mucus acts like elastic membrane. The snails use wave like muscle movements to glide forward efficiently.

2. Friction control: The mucus is a non Newtonian fluid. Its viscosity or thickness changes depending on the stress applied to it. This allows snails to control friction on surfaces as per their wish.

3. Adhesion: Snails can also move vertically and upside down, like a spider. This is possible due to adhesive force between their mucus and and surfaces.

4. Stress distribution: Shells of snails are logarithmic spirals. The shell closely resembles Fibonacci sequence and is a thing of mathematical beauty. The structure distributes stress and protects snail's life.

5. Thermal regulation: Snails also use their skin and shells for heat transfer. Surface of the shell and skin is highly reflective and shiny and reduces absorption of heat, keeping snails cool.

6. Moisture retention: In dry conditions, the mucus of snail is useful in controlling evaporation of water. Snails drink water by absorbing it through their slimy skin.

7. Vibration sensitivity: Snails do not have ears but respond to vibrations quickly. Snails detect external threat by vibrations as they are firmly attached to the surfaces.

8. Optics: Snails do not have very sharp eyes. Snails can only distinguish between bright and dark. Snails cannot see colors and only use elementary optics for movement.

9. Torsion: Snail's shell is coiled in such a way that it helps the snail stay balanced while moving. Some shells can grow very large and heavy over time, but the center of mass is shifted gradually keeping the snail perfectly healthy.

10. Viscoelasticity: Snail mucus is not just slippery, it is viscoelastic. Thus, the mucus can be used both as liquid and solid. This allows snails to hold on to surfaces, and defend itself against attack.

What Is the Twin Paradox? A Simple Guide to Einstein’s Theory of Relativity

Did you know that NASA conducted a study of the effects of spaceflight on twins. This was done to test Einstein's famous twin paradox experiment which is a result of relativity. Identical twins Scott Kelly and Mark Kelly were chosen and while Mark stayed on Earth, Scott spent a year aboard the international space station. You can read the results here.

What exactly is twin paradox? Let us understand Einstein's original idea first.

Time machine

Surely the idea of time machine takes our mind on a wild imaginary ride when we attempt to understand it. Time travel is a kind of travel not in space (which we know has three dimensions, length, width and height) but it is the travel in the fourth time dimension. Is it possible to travel in the past or in the future?

In non-relativistic or classical physics, the concept of time is that of absolute time, which is independent of any observer and is same throughout the universe. Same time flow on Jupiter as on Earth. This was thought of first by English scientist Sir Isaac Newton back in the day... who proposed that time progressed at consistent pace for everyone everywhere and is essentially imperceptible and mathematical in nature.

But in Einstein's relativity, time is not absolute. Meaning that time is perceivable and is not the same everywhere and for everyone. And we now know that the rates of time actually run differently depending on relative motion for different observers; time effectively passes at different paces so it might not be the same flow of time on Jupiter.

So, making a time machine might be possible if we can control the flow of time.

Twin paradox

There are two types of time travel: to the future and to the past. We already are moving into the future all the time at the tick of the seconds hand, but we're doing so at a regular rate. Could we make it so that this pace of time going forwards is increased, such that we go into the unseen future?

There is a way. Sending elementary particles on round trips in a particle accelerators at 99% of light speed is routine. The result is that the inner clock of such a travelling particle, say electron, runs much slower than that of a particle of the same species that remains at rest. Time slows for the fast moving particle.

Can this result from subatomic particles extend to larger human bodies? Einstein thought so... in his famous experiment "twin paradox" while he was working on the theory of relativity. In this, a hypothetical astronaut returns from a near-light speed voyage in space only to find his stay-at-home twin many years older than him, because travelling at high speeds has allowed the astronaut to experience only, let's say, one year of time, while ten years have gone by on the Earth.

The real paradox happens from the fact that there is "no favourable reference frame" in relativity. Why can’t the twin in the spaceship define himself as being at rest, let's say? And everyone on Earth is moving in that frame, oppositely. The Earth moves away at high speeds before returning to the still spaceship.

And if that is the frame, couldn’t the travelling twin apply time-dilation to everyone who stay on the Earth? By that argument, shouldn’t it be the humans of earth that remain younger once the twins are reunited? We all must eventually agree though that only one of the twins' perspective has to be the correct one. Which one is it then? So this is the actual "twin" or "dual" paradox of time dilation as put forth by Einstein in the 20th century.

Mind bending.

From general relativity, we can say that time passes more slowly for objects in strong gravitational fields than for the objects which stay far from such fields. There are all kinds of space and time distortions near black holes, where the gravity can become very intense. Thus if one of the twins is orbiting around a black hole and the other's orbiting around the earth the question of the paradox, "which twin is older" is answerable.

Back to the past

We have all watched "Back to the Future" and wondered how messed up it could get if we too did actually move backwards in time? And many scientists say the very premise of pushing a button and going back to yesterday violates the law of causality. However there are also some who think otherwise. Professor Michio Kaku has said, "Time is a river. It speeds up, meanders, and slows down. It can also have whirlpools and even fork into two rivers."

That last bit, "fork into two rivers," is important because then moving backwards in time could become at least thinkable. Because as soon as we push the button we go back into an alternate world or reality. We do not cause harm to our previous reality as in the case of "grandfather paradox". The idea was first proposed by British physicist David Deutsch who used the terminology of multiple universes to solve the grandfather paradox. Deutschian time travel involves the time traveler emerging in a different universe other than his own but very similar to his own.

Time travel will remain only conceptual and debatable except if we are able to develop enough advanced technology for it to become achievable. Until then we will use our earth bound telescopes as time machines. Because when you look into one you'd actually be looking into the past stages of the universe.. meaning that the star you observe today might not even exist in the first place. Turns out that if aliens knew exactly where to point their telescopes they could see dinosaurs at least in principle.

What Physics Tells Us About a Hypothetical Nuclear War Between India and Pakistan

India and Pakistan were recently involved in fresh tensions resulting in military actions by both countries. World leaders called for maintaining peace as any further escalation could potentially lead to a nuclear war in south Asia.

What impacts would a hypothetical nuclear war between India and Pakistan have on the world? Let us explore the physics behind the potential consequences of nuclear war in South Asia.

1. Blast destruction: Nuclear explosions release immense energy (E=mc²), causing blast waves and thermal radiation that kill millions instantly. The explosion can release energy as much as ~10²³ joules, causing a shockwave, flattening structures.

2. Underground or surface detonations release energy as mechanical waves, causing artificial localized earthquakes (seismic waves).

3. Thermal radiation from the fireball (~several million °C) ignites flammable materials, leading to large-scale fires. Shockwaves (pressure >10 psi) destroy buildings and critical infrastructure.

4. Radioactive isotopes (e.g., Cs-137, Sr-90) from fission reactions decay, emitting gamma rays and contaminating air, water, and soil. Post nuclear war, it would be impossible for any species to survive in the place.

5. High-altitude detonations produce gamma rays that ionize the atmosphere, generating electromagnetic pulses (EMPs) that disable electronics.

6. Soot from the explosions absorbs sunlight, reducing surface temperatures by 5-10°C for years due to aerosol scattering. This would lead to an unbearable nuclear winter.

7. Nitrogen oxides from high-temperature explosions catalyze ozone breakdown, increasing UV radiation exposure. This would not only impact the south Asia region but also the rest of the world for decades to come.

8. Reduced sunlight and temperature from nuclear winter disrupt photosynthesis, leading to crop failures.

9. Radiation sickness follows. Ionizing radiation (alpha, beta, gamma) disrupts cellular structures and DNA, causing acute and chronic health effects.

10. The nuclear war would speed up global disarmament efforts. Countries would volunteer to destruct their nuclear arsenal because people around the world could clearly see how dangerous nuclear weapons are.

credit: Geralt on pixabay