Science on This Day: December 17 | The First Powered Flight, Nuclear Fission and Humphry Davy
December 17 brings together three important stories from the history of science: the Wright brothers’ first successful powered flights in 1903, the experimental evidence that revealed nuclear fission in 1938, and the birth of chemist Humphry Davy in 1778. Each event shows a different way scientific knowledge develops, from testing an engineering design to interpreting unexpected experimental results and applying chemistry to practical problems.
For middle and high school science teachers, these events offer useful connections to forces and motion, atomic structure, chemical reactions, energy and the relationship between science and technology. They also provide a reminder that discoveries rarely happen in isolation. Progress often comes from repeated experiments, careful measurements and people building on earlier work.
December 17, 1903: The Wright brothers achieve powered flight
At 10:35 in the morning on December 17, 1903, Orville Wright took off in the Wright Flyer at Kitty Hawk, North Carolina. His flight lasted just 12 seconds and covered approximately 120 feet (37 metres). The aircraft flew only a short distance, but the achievement marked a major milestone: the first successful, sustained and controlled flights of a powered, heavier-than-air aircraft.
Orville and his brother Wilbur had spent years investigating how flying machines could be designed and controlled. They were not simply trying to attach an engine to something that could glide. They needed to solve several connected problems, including generating enough lift, producing forward thrust, keeping the aircraft balanced and giving the pilot control over its movement.
Their earlier experiments with kites and gliders were particularly important. Rather than relying only on calculations or copying existing designs, the brothers tested their ideas and used the results to improve their aircraft. They also built a wind tunnel to investigate wing shapes and compare how different designs behaved in moving air. Their experience repairing and building bicycles gave them useful mechanical skills, but their careful testing was central to their success.
The Wright Flyer used a small petrol engine to drive two propellers. The brothers also developed a system of controls that allowed the pilot to influence the aircraft's movement around three axes. This was a crucial advance: a flying machine needed not only to get into the air but also to remain controllable while responding to changing conditions.
The first flight was only the beginning. The brothers completed four flights that day, taking turns at the controls. On the final flight, Wilbur travelled 852 feet (about 260 metres) in 59 seconds. Their aircraft was damaged by a gust of wind after the flights, but the experiments had demonstrated that controlled powered flight was possible.
Classroom connection: forces, motion and engineering design
This event works well as an introduction to the forces acting on an aircraft. Students can consider how lift, weight, thrust and drag interact, and why an aircraft needs both propulsion and control. A useful question is: What would happen if an aircraft could generate enough lift to leave the ground but its pilot could not control its direction?
For a practical activity, students could design and test paper gliders, changing one variable at a time, such as wing shape or wing area. They can measure flight distance, record results and use evidence to decide which design performs best. This mirrors an important part of the Wright brothers' approach: test a design, analyse what happened and make improvements.
You could also connect the story to the wider development of flight, from early gliders to modern aircraft and spacecraft. My space exploration reading comprehension activity offers a further way for students to explore the science and technology involved in travelling beyond Earth's atmosphere.
December 17, 1938: Experiments reveal nuclear fission
In December 1938, chemists Otto Hahn and Fritz Strassmann conducted experiments in Berlin that produced a result they had not expected. They had been bombarding uranium with neutrons while investigating the products of nuclear reactions. When they analysed the resulting material, they found evidence of barium, an element much lighter than uranium.
This was a surprising finding. Scientists had been investigating whether bombarding heavy atomic nuclei with neutrons might produce new, heavier elements. The presence of barium suggested that something very different had happened: the uranium nucleus had split into smaller parts.
Hahn and Strassmann's results provided crucial experimental evidence for nuclear fission. The physicist Lise Meitner, who had previously worked with Hahn, had fled Nazi Germany and was living in Sweden. Working with her nephew, physicist Otto Frisch, she developed the physical explanation for the result. They recognised that the uranium nucleus could divide into two smaller nuclei and release a substantial amount of energy. Frisch helped introduce the term fission, borrowing a word used for the division of living cells.
This episode is a valuable example of how science works when observations do not fit expectations. Hahn and Strassmann's chemical analysis revealed an unexpected product. Meitner and Frisch helped explain what that result meant for the structure and behaviour of the atomic nucleus. Experimental evidence and theoretical interpretation played different but complementary roles.
Nuclear fission occurs when a heavy atomic nucleus splits into smaller nuclei. The process can release energy because the products have a different total nuclear binding energy from the original nucleus. In certain fission reactions, additional neutrons are also released. Those neutrons can trigger further fissions, potentially creating a chain reaction.
The discovery eventually contributed to technologies with very different consequences.
Nuclear reactors use controlled fission to produce heat, which can be used to generate electricity. Nuclear weapons exploit extremely rapid, uncontrolled energy release. Understanding fission is therefore important not only for physics but also for discussions about energy choices, safety, scientific responsibility and the impact of research on society.
Classroom connection: atomic structure and evidence
A strong starting question is: How could scientists know that a uranium nucleus had split if they could not directly see the nucleus? Students can examine how researchers identify reaction products and use indirect evidence to explain events at scales far smaller than a cell.
This can lead into lessons about protons, neutrons, isotopes, nuclear reactions and the difference between chemical and nuclear changes. In a chemical reaction, atoms are rearranged as bonds change. In a nuclear reaction, the nucleus itself changes, which can involve much larger energy changes.
For older students, the discovery also offers an opportunity to discuss how scientific credit is shared. Hahn and Strassmann made the key experimental observation, while Meitner and Frisch provided the theoretical interpretation. The subsequent history of nuclear physics raises questions about collaboration, recognition and the responsibilities that can accompany scientific discoveries.
If you are developing a lesson on energy or the social implications of science, you can browse my Teaching Astrophysicist resource store for additional science activities and classroom materials. Nuclear fission also provides a useful contrast with other ways of generating electricity, including chemical energy, solar power and wind energy.
December 17, 1778: Humphry Davy is born
Humphry Davy was born in Penzance, Cornwall, on December 17, 1778. He became one of Britain's most prominent chemists and made important contributions to electrochemistry, the study of how electrical energy and chemical change are connected.
At the beginning of the nineteenth century, scientists were exploring the capabilities of newly developed electric batteries. Davy used powerful batteries to pass electric currents through compounds, helping him isolate reactive elements that had not previously been obtained in pure form. In 1807, he isolated potassium and sodium from their compounds. He subsequently worked on other elements, including calcium and magnesium.
These experiments helped demonstrate that substances once thought to be indivisible or fundamental could be compounds made from different elements. They also showed that electricity could be used to bring about chemical changes, helping establish electrochemistry as an important field of science.
Davy's work was not limited to laboratory experiments. In 1815, he developed a miners' safety lamp in response to the danger of explosions caused by flammable gases in coal mines. One of the main hazards was firedamp, a gas mixture often containing methane. When methane mixes with air in suitable proportions, it can ignite or explode if exposed to a flame.
Davy's lamp surrounded the flame with a fine metal gauze. The gauze allowed air to enter and light to escape, but it also conducted heat away from the flame and helped prevent the flame from igniting flammable gas outside the lamp under appropriate conditions. This was an important application of scientific understanding to a serious workplace hazard.
The history is more complicated than a single inventor solving the problem. George Stephenson and William Reid Clanny also developed safety lamps, and the history of mining safety involved several competing designs. Davy's work nevertheless became particularly influential because it connected experiments with gases and heat to a practical engineering solution.
The lamp was not a complete answer to mining hazards. Safe ventilation, monitoring and wider workplace protections remained essential. Still, it demonstrates how scientific knowledge can help reduce risk when it is applied carefully to real conditions.
Classroom connection: electrolysis, elements and combustion
Davy's electrochemistry offers a natural introduction to electrolysis. Students can explore how an electric current can drive a chemical change that would not happen spontaneously under the same conditions. Depending on the age group and equipment available, this could involve a teacher demonstration or a suitable classroom investigation using a safe electrolyte.
His safety lamp provides another route into chemistry. Students can investigate the conditions needed for combustion, the role of oxygen and why methane presents an explosion risk when mixed with air. A model or diagram of the lamp can help them explain why a metal mesh changes the behaviour of a flame.
A useful discussion question is: How can the same scientific principle be useful in one setting but dangerous in another? Electricity can drive chemical reactions, for example, but electrical equipment also needs to be designed carefully around flammable gases. Students can use Davy's work to consider the connection between scientific understanding, engineering decisions and safety.
Bringing these three events into science lessons
The Wright brothers, the discovery of nuclear fission and Humphry Davy's work may appear to belong to separate areas of science, but they share a common theme: progress depends on combining evidence with explanation and practical problem-solving.
The Wright brothers used experiments to improve a machine. Hahn and Strassmann identified an unexpected reaction product, while Meitner and Frisch helped explain it. Davy used experimental chemistry to isolate elements and develop a lamp intended to make mining safer. Each story gives students an example of science as a process rather than simply a set of facts to memorise.
A short science-history activity can be used as a lesson starter, a discussion prompt or a way to connect a current topic with a real historical event. You might ask students to identify the problem each scientist or inventor was trying to solve, describe the evidence available and explain how the discovery changed what people could do or understand.
My December Science on This Day resource set makes this kind of activity easier to use throughout the month. It includes 132 STEM events across December in an interactive HTML resource, editable slides with discussion questions, a spreadsheet and a printable PDF. Teachers can select events by date or subject and use them as quick warm-ups or as introductions to a longer unit.
What else happened in science during December?
The rest of December offers more opportunities to connect science history with the curriculum. On December 18, the birth of physicist J. J. Thomson in 1856 provides a link to the discovery of the electron and changing models of atomic structure. Students can consider how new experimental evidence can force scientists to revise an accepted explanation of matter.
On December 20, the first electricity generated by a nuclear reactor at Experimental Breeder Reactor I in Idaho in 1951 offers a connection to nuclear energy and electricity generation. It provides a useful follow-up to the discovery of fission, helping students distinguish between a nuclear reaction and the systems used to turn released energy into electrical power.
On December 21, Apollo 8 launched on the first crewed mission to travel to the Moon and enter lunar orbit. The mission provides opportunities to discuss orbital motion, spacecraft navigation and the engineering challenges of sending people beyond low Earth orbit. The crew's famous Earthrise photograph also offers a way to consider how a change in perspective can influence how we view our planet.
Later in the month, December 25, 2021, marks the launch of the James Webb Space Telescope. Its journey and deployment provide examples of precision engineering, infrared astronomy and the challenges of building a telescope that must operate far from Earth.
From flight and nuclear physics to chemistry and space exploration, December's science history can help students see how scientific understanding develops through testing, collaboration and new evidence. One carefully chosen event can provide a memorable starting point for a lesson and show how the science studied in classrooms connects to discoveries that have shaped the world.
Thanks for reading
Cheers and stay curious
Oliver - The Teaching Astrophysicist
