Historical Events tagged with "light"

Turns out history loves a label—battles, breakthroughs, and the occasional disaster, all neatly tagged for your browsing pleasure. Because sometimes you just need every weird invention in one place.

Science & Technology

Definition of Metre Standardized by Light Speed

October 21st, 1983 41 years ago

The meter is now defined based on the speed of light, a significant shift from previous physical prototypes. This change, made by the 17th General Conference on Weights and Measures in Paris, is based on the precise speed of light in a vacuum. The decision is aimed at improving scientific accuracy, marking a pivotal moment in metrology. The use of light as a constant for measurement offers greater precision for scientists and researchers worldwide. The new definition allows for a universal standard that is not subject to physical deterioration.

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Science & Technology

Francis Baily's Observation of Baily's Beads

May 15th, 1836 188 years ago

During an annular eclipse, Francis Baily observed a phenomenon now known as 'Baily's beads.' This effect occurs when the rugged lunar landscape allows beads of sunlight to shine through in some places while being blocked in others. Baily's observations took place from a location in the vicinity of the Path of Annularity, enabling him to bring attention to this unique visual occurrence caused by the eclipse.

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Science & Technology

James Bowman Lindsay's Electric Light Demonstration

July 25th, 1835 189 years ago

In Dundee, Scotland, James Bowman Lindsay showcased his remarkable constant electric light at a public meeting. This demonstration, attended by notable members of the community, was aimed at revealing the potential of electric lighting to transform everyday life. Lindsay’s invention utilized a simple apparatus that captivated the audience, presenting a clear and steady light source, contrasting with the flickering candles and gas lamps common at the time. The event sparked interest in electric lighting, paving the way for future advancements in the field.

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Science & Technology

Fresnel's Breakthrough on Light Diffraction

July 29th, 1818 206 years ago

Augustin Fresnel presented his groundbreaking memoir on light diffraction to the French Academy of Sciences. This work meticulously detailed the behavior of light as it interacts with obstacles, particularly the phenomenon of diffraction, wherein light seemingly spreads into shadows and around edges. Fresnel's research countered long-standing criticisms of the wave theory of light, providing compelling evidence that established the wave nature of light more clearly than ever before. His insights not only advanced the understanding of optical physics but also laid the groundwork for future innovations in this field.

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Science & Technology

Fresnel Signs Theory of Diffraction Note

April 19th, 1818 207 years ago

Augustin Fresnel, a prominent French physicist, signed a crucial preliminary note elucidating the theory of diffraction. This document, significant in understanding light behavior, was deposited the following day. The groundbreaking work culminates in what today is referred to as Fresnel integrals—a fundamental aspect of wave optics. His research opened pathways to advancements in both physics and engineering, particularly in optics.

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Science & Technology

Brewster Announces Biaxial Crystals Discovery

January 15th, 1818 207 years ago

David Brewster presented his findings on doubly-refracting crystals to the Royal Society, highlighting the biaxial class. Simultaneously, Augustin-Jean Fresnel prepared a supplement regarding the reflection of polarized light, demonstrating ongoing advancements in optics and light behavior, leading to significant developments in the field.

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Science & Technology

Ole Rømer Measures Speed of Light

November 21st, 1676 348 years ago

Danish astronomer Ole Rømer quantitatively measured the speed of light using observations of Jupiter's moon Io. He noted discrepancies in Io's orbital timing based on Earth's varying distance from Jupiter, leading to a groundbreaking calculation of light's speed at approximately 220,000 kilometers per second. His innovative approach established a foundation for future studies in optics and astronomy.

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