The word light is probably most often used in the sense of visible light, or illumination, or concepts of that ilk where it is not meant to be the opposite of "heavy".  "Light", whatever it may be, is a chunk of the electromagnetic spectrum, which includes radio, TV, radar, microwaves, and hard radiation.  Beyond that, Schrödinger's wave equation extends it to particles, so it is somewhat universal and foundational.  Where light or other emf falls on the spectrum is determined by its frequency (f) or wavelength (λ), which are related by the formula λ = c/f where c is the "speed of light".  The visible spectrum typically runs from about 700 nanometers (RED) to around 380 nanometers (VIOLET).

So, why do we have an International Day of Light?  Damnfino.  Perhaps because the future appears so dark and bleak as to ecology, climate, poverty and all things socio-political?  Perhaps on the theory that shining a light into the dark corners will expose corruption and deceit, something unlikely in these times of unbridled censorship, even before the creation of MiniTruth, brought to us by those who gave us babies being tossed out of incubators, the Tonkin Gulf Incident, Weapons of Mass Destruction, and untold numbers of other fabulous tales and fictions.  Perhaps it is supposed to remind us of the light at the end of the tunnel, always there and ever receding, like Ahab, beckoning us to follow it?
 

On this day in 1918 1918 – The Sedition Act of 1918 was passed by the U.S. Congress, making criticism of the government during wartime an imprisonable offense. It was repealed less than two years later and then more recently gradually reinstated through various laws and edicts like the "Patriot Act" and section 1021 of the 2012 NDAA and the like and then even extended to include assassination of those living abroad.  Of course, probably the biggest change is that we somewhere along the way transitioned to an evidence free reality, where accusations and assertions, sometimes called "assessments" are deemed to be an adequate substitute for actual facts supported by actual evidence.

On this day in history:

11527 – The Florentines drove out the Medici for a second time and Florence became a republic

1532 – Sir Thomas More resigned as Lord Chancellor of England.

1739 – The Marathas defeated the Portuguese army at the Battle of Vasai.

1812 – The Treaty of Bucharest endied the Russo-Turkish War.

1832 – Juan Godoy discovered the rich silver outcrops of Chañarcillo sparking the Chilean silver rush.

1842 – The first major Oregon Trail wagon train heading for the Pacific Northwest left Elm Grove, Missouri, with 100 colonizers

1866 – The US Congress established the nickel.

1877 – The 16 May 1877 crisis occurred in France,

1888 – Nikola Tesla delivered a lecture describing the equipment that would allow efficient generation and use of alternating currents to transmit electric power over long distances.

1891 – The International Electrotechnical Exhibition opened in Frankfurt, Germany,

1916 – The UK and the French Third Republic signed the Sykes-Picot Agreement partitioning former Ottoman territories such as Iraq and Syria.

1918 – The Sedition Act of 1918 was passed by the U.S. Congress, making criticism of the government during wartime an imprisonable offense. It was repealed less than two years later.

1919 – A naval Curtiss NC-4 aircraft commanded by Albert Cushing Read left Trepassey, Newfoundland, for Lisbon via the Azores on the first transatlantic flight 

1943 – The Warsaw Ghetto Uprising ended.

1951 – The first regularly scheduled transatlantic flights between Idlewild Airport in New York City and Heathrow Airport in London began

1960 – Theodore Maiman operated the first optical laser

1961 – Park Chung-hee led a coup d'état to overthrow the Second Republic of South Korea.

1966 – The Chinese Communist Party issued the "May 16 Notice", starting the Cultural Revolution.

1969 – The Soviet space probe Venera 5 landed on Venus.

1988 – A report by the Surgeon General of the US stated that the addictive properties of nicotine were similar to those of heroin and cocaine.

2005 – Kuwait permitted women's suffrage

2011 – STS-134,  the final flight for Space Shuttle Endeavour, was launched from the Kennedy Space Center

Some people who were born on this day:

Children are to be guided to make a beginning in all the arts and sciences without interference with their spontaneity, the instinct of imitation being so used as to give them order without constraining them.

~~     Elizabeth Palmer Peabody

1606 – John Bulwer, doctor
1718 – Maria Gaetana Agnesi, mathematician and philosopher
1763 – Louis Nicolas Vauquelin, pharmacist and chemist
1804 – Elizabeth Palmer Peabody, educator who founded the first U.S. kindergarten
1821 – Pafnuty Chebyshev, mathematician and statistician
1831 – David Edward Hughes, physicist, co-invented the microphone 
1862 – Margaret Fountaine, lepidopterist and diarist
1876 – Fred Conrad Koch, biochemist and endocrinologist
1888 – Royal Rife, microbiologist and instrument maker
1890 – Edith Grace White, ichthyologist
1898 – Tamara de Lempicka, painter
 
1903 – Charles F. Brannock, inventor and manufacturer
1906 – Alfred Pellan, painter and educator
1906 – Margret Rey, author and illustrator
1910 – Olga Bergholz, poet and author
1912 – Studs Terkel, historian and author
1913 – Woody Herman, singer, saxophonist, and clarinet player
1914 – Edward T. Hall, anthropologist and author
1919 – Liberace, pianist and entertainer
1919 – Ramon Margalef, ecologist and biologist
1923 – Victoria Fromkin, linguist and academic
1924 – Barbara Bachmann, microbiologist
1925 – Nancy Roman, astronomer (
1929 – Betty Carter, singer and songwriter
1929 – Adrienne Rich, poet, essayist, and feminist
1930 – Friedrich Gulda, pianist and composer
1937 – Yvonne Craig, ballet dancer and actress
1938 – Ivan Sutherland, computer scientist and academic
1944 – Billy Cobham, drummer, composer, and bandleader
1946 – Robert Fripp, guitarist, songwriter and producer
1947 – Cheryl Clarke, writer
1950 – Georg Bednorz, physicist and academic
1950 – Ray Condo, singer, songwriter, and guitarist
1951 – Jonathan Richman, singer, songwriter, and guitarist
1953 – Richard Page, singer, songwriter, and bass player
1957 – Yuri Shevchuk, singer, songwriter, and guitarist
1964 – Boyd Tinsley, singer, songwriter,  and violinist
1965 – Krist Novoselic, bass player, songwriter, author, and activist
1965 – Tanel Tammet, computer scientist, engineer, and academic
1966 – Janet Jackson, singer, songwriter, dancer, and actress
1966 – Scott Reeves, singer, songwriter, and actor
1968 – Ralph Tresvant, singer and producer
1970 – Danielle Spencer,  singer, songwriter and actress
1971 – Rachel Goswell, singer, songwriter, and guitarist
1977 – Emilíana Torrini, singer and songwriter
1992 – Kirstin Maldonado, singer and songwriter

Some people who died on this day:

You've got to bear it in mind that nobody ever lived is specially privileged; the axe can fall at any moment, on any neck, without any warning or any regard for justice.

~~     James Agee

1620 – William Adams, sailor, navigator, and samurai
1669 – Pietro da Cortona, painter and architect, designed the Santi Luca e Martina 
1703 – Charles Perrault, author and academic
1818 – Matthew Lewis,  author and playwright
1830 – Joseph Fourier, mathematician and physicist
 
1910 – Henri-Edmond Cross, Neo-Impressionist painter
1938 – Joseph Strauss, engineer, co designed The Golden Gate Bridge 
1944 – George Ade, journalist, author, and playwright
1947 – Frederick Gowland Hopkins, biochemist and academic
1953 – Django Reinhardt, guitarist and composer
1955 – James Agee, novelist, screenwriter, and critic
1979 – A. Philip Randolph, union leader and activist
1981 – Ernie Freeman, pianist, composer, and bandleader
1984 – Irwin Shaw, playwright, screenwriter, novelist, and short story writer
1990 – Sammy Davis Jr., singer, dancer, and actor
1990 – Jim Henson, puppeteer, director, producer, and screenwriter, created The Muppets 
1993 – Marv Johnson,  singer, songwriter, and pianist
2010 – Ronnie James Dio, singer, songwriterand producer
2010 – Hank Jones, pianist, composer, and bandleader
2012 – Chuck Brown, singer, songwriter, guitarist, and producer
2013 – Heinrich Rohrer, physicist and academic

Some Holidays, Holy Days, Festivals, Feast Days, Days of Recognition, and such:

International Day of Light
Biographers Day
Love a Tree Day
National Mimosa Day

Today's Tunes

Woody Herman

Liberace

Betty Carter

Friedrich Gulda

Billy Cobham

Robert Fripp

Boyd Tinsley

Janet Jackson

Django Reinhardt

Ernie Freeman

Sammy Davis Jr.

Marv Johnson

Hank Jones

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