Why are snowflakes like this?

Veritasium
30 Nov 202118:49
EducationalLearning
32 Likes 10 Comments

TLDRThe video script details the fascinating process of snowflake formation, led by Dr. Ken Libbrecht, a renowned snowflake expert. It begins with the creation of snowflakes in a lab by manipulating conditions such as temperature and humidity to control the growth and branching of ice crystals. The unique hexagonal symmetry of snowflakes is attributed to the molecular structure of water. The script also delves into the history of snowflake study, referencing Wilson A. Bentley's pioneering work and the Nakaya Diagram, which illustrates how temperature and super saturation levels affect snowflake types. Dr. Libbrecht's experiments with 'identical twin snowflakes' showcase the potential for creating similar snowflakes under controlled conditions. The video unravels the mystery behind the varying shapes of snowflakes, proposing that nucleation barriers, influenced by temperature, determine the growth of ice crystals into plates or columns. This insightful exploration of snowflake physics not only satisfies scientific curiosity but also highlights the beauty and complexity of these natural wonders.

Takeaways
  • 🔬 Dr. Ken Libbrecht, a physicist and snowflake expert, creates snowflakes in the lab by manipulating temperature and humidity to control their growth.
  • 🌡️ The growth of snowflakes is influenced by the temperature and humidity conditions, which can be used to predict and control their shape.
  • ❄️ Snowflakes exhibit six-fold radial symmetry due to the molecular structure of water, which forms a hexagonal lattice when freezing.
  • 🎨 Snowflakes come in various forms such as plates, columns, needles, cups, and bullets, each resulting from different environmental conditions during their formation.
  • 📈 The Nakaya Diagram illustrates how different snowflake shapes are associated with specific temperature and super saturation levels.
  • 🔍 Wilson A. Bentley was the first to photograph a snowflake up close in 1885 and proposed that no two snowflakes are alike due to their unique growth conditions.
  • 🧬 Despite the lack of a physical blueprint, snowflakes form spontaneously from water vapor freezing into ice, resulting in a variety of shapes.
  • 🧊 Snowflakes are flat structures, usually millimeters in diameter but only micrometers thick, with edges as narrow as razorblades.
  • 🤔 The mystery of why snowflakes have intricate and differing designs, yet maintain perfect symmetry, is due to the uniform conditions experienced by both sides of a snowflake as it grows.
  • 🧞‍♂️ Dr. Libbrecht's experiments with 'identical twin snowflakes' in the lab show that under controlled conditions, snowflakes can grow to be very similar.
  • 🌟 The study of snowflakes is not just for scientific curiosity but also has practical applications, such as in understanding the physics of ice formation.
Q & A
  • What is the first step in creating snowflakes in the lab as described in the transcript?

    -The first step in creating snowflakes in the lab involves turning on 2000 volts.

  • What is the diameter of the tips of the needles used in the lab to create snowflakes?

    -The tips of the needles used in the lab to create snowflakes are about a hundred nanometers in diameter.

  • What is Dr. Ken Libbrecht's claim to fame in relation to snowflakes?

    -Dr. Ken Libbrecht is known as the 'snowflake guy' and was the snowflake consultant for the movie 'Frozen'. He also had his pictures of snowflakes used for the US Post Office snowflake stamps.

  • How does Dr. Libbrecht describe his process of creating snowflakes?

    -Dr. Libbrecht describes his process as designing 'designer snowflakes' on the fly, without the use of a computer, which results in each snowflake being slightly different.

  • What is the significance of the temperature and humidity control in the snowflake creation process?

    -Temperature and humidity control are crucial as they determine the growth conditions and the formation of branches in the snowflakes. By adjusting these factors, Dr. Libbrecht can influence the shape and structure of the snowflakes.

  • What is the historical significance of Wilson A. Bentley in the study of snowflakes?

    -Wilson A. Bentley was the first to take a close-up photograph of a snowflake in the wild in 1885. He originated the idea that no two snowflakes are alike, taking over 5,000 photos of snowflakes throughout his life.

  • What is the typical thickness of a snowflake?

    -Snowflakes are typically a few micrometers thick, despite being millimeters in diameter.

  • What are the different forms that snowflakes can take?

    -Snowflakes can take various forms such as hollow columns, needles, cups, bullets, and capped columns.

  • How many different types of snowflakes has Dr. Libbrecht identified?

    -Dr. Libbrecht has identified 35 different types of snowflakes, although other charts have listed more.

  • What is the role of super saturation in the formation of snowflakes?

    -Super saturation occurs when there are more water molecules in the air than would be in equilibrium at a given temperature. This excess provides the necessary conditions for water molecules to condense onto dust particles, forming the initial droplets that can freeze and grow into snowflakes.

  • What is the Nakaya Diagram and how does it help in understanding snowflake formation?

    -The Nakaya Diagram is a tool that summarizes the findings of Ukichiro Nakaya, showing how different types of snowflakes form under various temperature and super saturation conditions. It helps in understanding the rough history of any snowflake by revealing the conditions under which it grew.

  • How does Dr. Libbrecht's hypothesis explain the formation of different snowflake structures at various temperatures?

    -Dr. Libbrecht's hypothesis suggests that nucleation barriers, which are known to vary with temperature, affect the growth of different facets of a snowflake. He proposes that narrow facets have different nucleation barriers than large flat ones, leading to the formation of plates and columns at specific temperatures.

Outlines
00:00
🔬 Snowflake Creation and Design

Dr. Ken Libbrecht, known as the 'snowflake guy,' demonstrates the process of creating snowflakes in a lab setting by applying 2000 volts. He discusses the precision of the needles used and shares his experience as a consultant for the movie 'Frozen.' Ken also talks about his work with the US Post Office on snowflake stamps and his books on snowflakes. He describes himself as a 'designer snowflake' artist, manually creating each unique snowflake by adjusting conditions like temperature and humidity to control the growth and branching of the snowflake. The process involves growing the snowflake at -13 Celsius, then lowering the temperature and increasing humidity to encourage branching. Ken also explains how adjusting these conditions can lead to different snowflake structures and how he can predict the growth patterns, comparing his creations to those found in nature.

05:02
❄️ The Science of Snowflake Formation

The video delves into the scientific explanation of snowflake formation, starting with water evaporating into vapor and rising to form super-saturated conditions where water molecules condense on dust particles. The unique hexagonal shape of snowflakes is due to the molecular structure of water, which forms a lattice held together by hydrogen bonds. As the snowflake grows, the rough surfaces of the crystal facets allow water vapor molecules to stick more readily, leading to the development of a faceted shape. The growth of a snowflake is influenced by temperature and humidity, with different structures forming at various temperatures, as illustrated by the Nakaya Diagram. The video also highlights the work of Ukichiro Nakaya and how his research has helped understand the relationship between snowflake shape and the environmental conditions during its formation.

10:07
🌡️ Snowflake Shapes and Ken's Hypothesis

Ken explores the idea that snowflakes can reveal the conditions under which they grew, suggesting that weather patterns and temperature changes can lead to different snowflake structures like capped columns. He explains the concept of nucleation barriers and how they vary for different facets of a growing snowflake, leading to the formation of plates or columns. Ken's hypothesis addresses the mystery of why snowflakes form plates and columns at specific temperatures, proposing that narrow facets have different nucleation barriers than large flat ones, causing dips in the barriers at certain temperatures. His experiments support this theory, providing insight into the molecular physics of ice and the diverse shapes of snowflakes.

15:07
🎓 The Drive to Understand Snowflakes

The video concludes with Ken's personal motivation for studying snowflakes, driven by the desire to understand the complex processes behind their formation. He compares his work to other scientific fields, such as astronomy, where the practical applications are not always immediately apparent. Ken's passion for discovering how snowflakes work is fueled by the scientific curiosity to solve a mystery. The video also includes a sponsorship message for Brilliant, an interactive learning platform that allows users to explore and master various topics, including math, science, and computer science, through problem-solving and engaging courses.

Mindmap
Keywords
💡Snowflake
Snowflakes are ice crystals that form in the atmosphere under specific conditions, characterized by their unique and intricate six-fold radial symmetry. In the video, snowflakes are the central theme, illustrating the natural phenomenon of their formation and the scientific inquiry into their complexity and variety. The video discusses how snowflakes grow under different temperature and humidity conditions, leading to their diverse shapes.
💡Super Saturation
Super saturation refers to a state where the air contains more water molecules than would typically be present at a given temperature, leading to the formation of tiny droplets that can freeze and form snowflakes. In the context of the video, super saturation is a critical condition for snowflake formation, as it is mentioned when discussing the controlled environment for creating snowflakes in the lab.
💡Hexagonal Crystal
A hexagonal crystal is a type of crystal structure that has six sides, which is common in snowflakes due to the molecular structure of water. The video explains that water molecules naturally form a hexagonal lattice because of the polarity of the molecule, leading to the characteristic shape of snowflakes. This shape is fundamental to understanding how snowflakes grow and why they have six-fold symmetry.
💡Nucleation Barriers
Nucleation barriers are the energy hurdles that must be overcome for a substance to form a stable nucleus that can grow into a larger structure, such as a snowflake. The video discusses how these barriers vary depending on the temperature and the facets of the growing ice crystal, which in turn affects the shape of the snowflake. The concept is central to understanding Ken Libbrecht's hypothesis about the formation of different snowflake structures.
💡Sapphire Substrate
A sapphire substrate is a smooth surface, made of sapphire, on which ice crystals can grow in a laboratory setting. In the video, Dr. Ken Libbrecht uses a sapphire substrate to create snowflakes under controlled conditions. The substrate allows for the growth of snowflakes with minimal interference, enabling the study of their formation and structure.
💡Wilson A. Bentley
Wilson A. Bentley was an American meteorologist who is known for his pioneering photographs of snowflakes, taken in 1885. He is credited with the idea that no two snowflakes are alike, having captured over 5,000 snowflake images throughout his life. His work is highlighted in the video as foundational to the study and appreciation of snowflake diversity and complexity.
💡Nakaya Diagram
The Nakaya Diagram is a chart that illustrates the relationship between temperature and super saturation levels with the types of snowflakes that form. It was developed by Ukichiro Nakaya in the 1930s and is used to predict the shapes of snowflakes based on environmental conditions. The video discusses how the diagram helps scientists understand the conditions under which different snowflake types form.
💡Hydrogen Bond
A hydrogen bond is a type of dipole-dipole interaction that occurs between a hydrogen atom covalently bonded to an electronegative atom and another electronegative atom. In the context of the video, hydrogen bonds are what create the hexagonal molecular lattice structure of ice, which is the basis for the formation of snowflakes. The video explains how the polarity of water molecules leads to the formation of these bonds, resulting in the characteristic hexagonal shape of snowflakes.
💡Identical Twin Snowflakes
Identical twin snowflakes refer to two snowflakes that are grown next to each other in a laboratory under identical conditions, resulting in very similar structures. In the video, Dr. Ken Libbrecht experiments with growing such snowflakes to test the commonly held belief that no two snowflakes are alike. The creation of identical twin snowflakes challenges this notion and showcases the precision with which snowflake growth can be controlled in a lab.
💡Capped Column
A capped column is a type of snowflake that begins its growth as a column but then develops plates at the ends due to changes in temperature. The video describes this as one of Dr. Libbrecht's favorite kinds of snowflakes. It illustrates the impact of temperature changes on the growth patterns of snowflakes and contributes to the overall diversity of snowflake shapes.
💡Brilliant
Brilliant is an interactive learning platform mentioned in the video that offers courses in math, science, and computer science. It is highlighted as a resource for those who want to delve deeper into topics like geometry, which is related to the study of snowflake shapes. The platform is used as an example of how interactive learning can help individuals master complex subjects, such as the physics behind snowflake formation discussed in the video.
Highlights

Dr. Ken Libbrecht creates snowflakes in the lab using a unique process involving voltage and precise environmental conditions.

The snowflakes created in the lab are real and must meet high standards for public acceptance, as seen in the movie 'Frozen' and on US Postage stamps.

Dr. Libbrecht has authored books on snowflakes, contributing to the popular and scientific understanding of these natural wonders.

Snowflake designing is an on-the-fly process without computer assistance, resulting in unique, handcrafted designs.

Snowflake growth can be manipulated by adjusting temperature and humidity to produce different branch structures.

Snowflakes exhibit six-fold radial symmetry due to the molecular structure of water and the formation of hydrogen bonds.

Wilson A. Bentley was the first to photograph a snowflake up close and proposed that no two snowflakes are alike.

Snowflakes come in various forms such as hollow columns, needles, cups, and bullets, each with its unique growing conditions.

Dr. Libbrecht has identified 35 distinct types of snowflakes, noting the challenge in defining a type due to their variability.

Snowflake formation is influenced by the temperature and super saturation levels, as illustrated in the Nakaya Diagram.

The shape of a snowflake can reveal its history, showing the conditions it grew under.

Snowflakes are intricate because the temperature and humidity at each moment of their growth determine the structures formed.

In the lab, identical twin snowflakes can be created by controlling the growth conditions.

Dr. Libbrecht's experiments have shed light on the nucleation barriers of ice and how they affect snowflake formation at various temperatures.

The hypothesis that narrow facets have different nucleation barriers, which explains the variety of snowflake forms at different temperatures, has been supported by Ken's lab experiments.

Dr. Libbrecht's research may have finally explained the molecular physics behind the diverse shapes of snowflakes after 85 years since Nakaya's introduction of his diagram.

The study of snowflakes is driven by scientific curiosity and the desire to understand the underlying mechanisms of their formation.

The video is sponsored by Brilliant, an interactive learning platform that helps users master topics through problem-solving.

Transcripts
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