Science on This Day: November 20 | Edwin Hubble, Fractal Geometry and the International Space Station
November 20 brings together some very different stories from science and technology. It is the birthday of an astronomer whose observations changed our understanding of the universe, a mathematician who helped us recognise patterns across different scales, and the anniversary of a launch that began the assembly of the International Space Station. It is also the date Windows 1.0 was released, an early milestone in the development of personal computing.
These events offer science teachers opportunities to connect astronomy, mathematics, engineering and computing to the people, ideas and technologies that shape our world. They also make useful short starters, discussion prompts or introductions to longer investigations.
Edwin Hubble: Discovering a Universe Beyond Our Galaxy
On November 20, 1889, Edwin Hubble was born in Marshfield, Missouri, in the United States. His astronomical observations would help transform humanity’s understanding of the size and structure of the universe.
In the early twentieth century, astronomers were still working to establish the true scale of the cosmos. Some cloudy objects visible through telescopes, known as nebulae, were thought to be relatively nearby features within the Milky Way. Hubble used observations from powerful telescopes, including the 100-inch Hooker telescope at Mount Wilson Observatory, to investigate these objects.
By studying stars within certain nebulae, Hubble helped establish that some of these objects were separate galaxies far beyond the Milky Way. The universe was much larger than many people had imagined.
Hubble also contributed to the evidence that the universe is expanding. By examining the light from distant galaxies and comparing their distances with their apparent movement away from us, astronomers found a broad relationship: more distant galaxies tend to recede faster. Hubble's work helped persuade the scientific community of this expanding-universe picture, although the story also depended on observations and theoretical work by other scientists.
This is an excellent opportunity to explore how scientific knowledge changes when new evidence becomes available. Students can compare an older model of a universe contained within the Milky Way with the modern understanding of billions of galaxies. What observations would be needed to distinguish a distant galaxy from a cloud of gas inside our own?
For a classroom discussion, ask students: How can scientists establish that something is far beyond the limits of what they can directly visit? This question connects astronomy with measurement, inference and the limits of scientific instruments.
NASA's biography of Edwin Hubble provides a useful starting point for further reading. His legacy also lives on in the Hubble Space Telescope, which has allowed astronomers to study galaxies, stars and distant objects across the universe.
Benoît Mandelbrot: Finding Patterns Across Different Scales
November 20, 1924, marks the birth of Benoît Mandelbrot, the mathematician closely associated with the development and popularisation of fractal geometry.
A fractal is a mathematical pattern or structure that can show similar features at different scales. Some fractals contain repeating shapes that remain recognisable as you zoom in, although the exact properties depend on the pattern being studied. Fractal ideas have helped scientists and mathematicians describe forms that are difficult to represent using simple shapes such as circles, squares and straight lines.
Think about the branching structure of a tree, the outline of a coastline, the shape of a snowflake or the branching pattern of blood vessels. These examples are not all perfect mathematical fractals, but they help introduce the idea that nature often contains patterns repeated across different sizes.
Mandelbrot's work helped bring fractal geometry into wider use, including in the study of complex shapes and irregular structures. It also offered a new way to think about mathematical patterns that traditional geometry could struggle to describe neatly.
This topic works particularly well across mathematics and science. Students can investigate branching patterns in plants, compare the outlines of coastlines at different map scales, or generate a simple fractal using repeated geometric steps. They can then consider whether the pattern is genuinely repeating, approximately similar, or simply looks irregular.
A useful discussion question is: Why might a scientist need a different kind of mathematics to describe a coastline than to describe a football? Students can explore how scale affects measurement and why the length of a coastline may depend on the size of the measuring unit used.
For younger learners, start with photographs of ferns, trees, river networks or snowflakes and ask students to identify repeating features. Older students can explore iterative patterns and use mathematical rules to generate their own designs.
Mandelbrot's story is a reminder that mathematics is not only about solving equations. It also gives us tools for describing the complexity of the natural world.
Zarya: The First Building Block of the International Space Station
On November 20, 1998, the Zarya module launched from Baikonur Cosmodrome in Kazakhstan aboard a Russian Proton rocket. This was the first component launched for the International Space Station (ISS), beginning the orbital assembly of one of the most ambitious engineering projects ever undertaken.
Zarya, whose name is often translated as “sunrise” or “daybreak,” was built in Russia with funding from the United States. It provided early power, propulsion and control functions for the developing station. It was not a complete space station on its own. Instead, it was the first part of a much larger structure that would be assembled piece by piece in orbit.
The next major component, the Unity module, was launched aboard the space shuttle Endeavour in December 1998. Astronauts used the shuttle's robotic arm to connect the modules. More elements were added over subsequent years, creating a large orbital laboratory where crews could live and conduct research.
The ISS is a useful example of engineering as a process rather than a single invention.
Every module must be designed to work with the others. Connections, power supplies, life-support systems, communications, temperature control and orbital operations all need to function together. Engineers also have to consider how equipment will be launched, connected and maintained in an environment where mistakes can be difficult or dangerous to correct.
The station also illustrates international cooperation. Its development involved multiple countries, space agencies, contractors and research teams. Such cooperation brings together expertise and resources, but it also creates challenges involving shared standards, logistics, communication and decision-making.
For a classroom activity, ask students to design a small modular space station. Each group could develop one module, such as living quarters, a laboratory, power generation or communications. The class must then agree on how the modules will connect and what each part needs from the others.
This can lead to a valuable question: What makes a collection of separate pieces into one functioning system? Students can apply the same thinking to ecosystems, electrical circuits, transport networks or the human body.
NASA's overview of the Zarya module explains its role in the station's assembly, while its history of International Space Station construction provides further context.
Another November 20 milestone: Windows 1.0
On November 20, 1985, Microsoft released Windows 1.0, introducing a graphical interface for personal computers running MS-DOS. It was an early step in the development of the Windows environment that would become familiar to computer users around the world.
Instead of relying only on typed commands, users could interact with on-screen windows, menus and a mouse. The first version was limited compared with modern computers, but it helped develop the idea that people could interact with software through visual elements.
This event is a useful connection between computing, design and human behaviour.
Students can compare a command-line interface with a graphical interface and consider how design choices affect accessibility, efficiency and the way people learn to use technology.
It also creates an opportunity to discuss how technological change builds on earlier inventions. Modern computers did not appear fully formed. They developed through many changes in hardware, software and interface design.
How to use November 20 in your science classroom
Science history can be more than a date and a name on the board. These events can act as short introductions to bigger ideas, giving students a real-world reason to think about evidence, patterns and engineering decisions.
For a quick starter, display one event and ask students to write down what they already know, what they would like to find out and what evidence could help answer their questions. You could also ask students to connect each event to a topic they are currently studying: galaxies and evidence in astronomy, patterns and scale in mathematics, systems engineering in physics, or interfaces and design in computing.
For a longer activity, students could select one event and create a short explanation of why it mattered, supported by evidence from a reliable source. They could then compare how scientific discoveries, mathematical ideas and technological inventions affect society in different ways.
If you want ready-to-use examples throughout the month, my November Science on This Day resource set contains 109 STEM stories across the 30 days of November. It includes an interactive HTML version with filters and classroom display features, editable Google Slides with discussion questions, a filterable spreadsheet and a PDF version. You can choose a single event for a warm-up or use the collection to build a regular science-history routine.
You can also explore the wider Teaching Astrophysicist resource store for free and paid science teaching materials in different formats.
Looking ahead: November 21 and beyond
November 21 offers more opportunities to connect science with everyday life. In 1783, Jean-François Pilâtre de Rozier and the Marquis d'Arlandes made an early untethered human balloon flight in a Montgolfier hot-air balloon, providing a way to explore buoyancy, density and the behaviour of heated air. On the same date in 1877, Thomas Edison announced the phonograph, a device that recorded and reproduced sound. This is a natural link to sound waves, vibrations and how information can be stored.
November 21 also marks the publication of Albert Einstein's 1905 paper on the relationship between mass and energy, offering a route into one of the most important ideas in modern physics: the relationship expressed as (E = mc^2).
On November 22, the birth of physicist Louis Néel in 1904 provides another opportunity to discuss magnetism and how the arrangement of magnetic moments inside a material affects its properties.
Whether you are teaching astronomy, physics, biology, chemistry, mathematics or computing, science history gives students a way to see how ideas develop and how discoveries connect to the world around them. A short event can become a question, a question can lead to an investigation, and an investigation can help students build a deeper understanding of the science behind the story.
Thanks for reading
Cheers and stay curious
Oliver - The Teaching Astrophysicist
