1800 ⟶ William Herschel Discovers Infrared Radiation
William Herschel splits sunlight through a prism and with a ...
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🪐 William Herschel Discovers the Planet Uranus
Amateur astronomer William Herschel discovers the planet Uranus, although he at first mistakes it for a comet. Uranus is the first planet to be discovered beyond Saturn, which was thought to be the most distant planet in ancient times.⟶
AstronomyPlanetary ScienceSolar SystemDiscoveryTelescopeHerschel18th CenturyScientific Revolution
United Kingdom🌡️ William Herschel Discovers Infrared Radiation
William Herschel splits sunlight through a prism and with a thermometer, measures the energy given out by different colours. He notices a sudden increase in energy beyond the red end of the spectrum, discovering invisible infrared and laying the foundations of spectroscopy.⟶
PhysicsOpticsSpectroscopyInfrared RadiationElectromagnetic SpectrumHerschel19th Century
United Kingdom☄️ Giuseppe Piazzi Discovers Ceres, Later Classified as an Asteroid
Italian astronomer Giuseppe Piazzi discovers what appears to be a new planet orbiting between Mars and Jupiter, and names it Ceres. William Herschel proves it is a very small object, calculating it to be only 320 km in diameter, and not a planet. He proposes the name asteroid, and soon other similar bodies are being found. We now know that Ceres is 932 km in diameter, and is now considered to be a dwarf planet.⟶
AstronomyAsteroidCeresPlanetary ScienceHerschel19th CenturySolar System
ItalyUnited Kingdom💡 Thomas Young Proposes Wave Theory of Light
PhysicsOpticsWave Theory of LightYoungLight19th Century
United Kingdom☀️ Discovery of Helium
Astronomers notice a new bright emission line in the spectrum of the Sun's atmosphere during an eclipse. The emission line is caused by an element's giving out light, and British astronomer Norman Lockyer concludes that it is an element unknown on Earth. He calls it helium, from the Greek word for the Sun. Nearly 30 years later, helium is found on Earth.⟶
AstronomyPhysicsHeliumLockyerSpectroscopy19th CenturyElementsSolar System
United Kingdom🔢 Johannes Rydberg: Rydberg Formula
PhysicsAtomic PhysicsSpectroscopyRydberg FormulaJohannes RydbergQuantum Mechanics19th Century
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