Time Travel Tuesday #timetravel a look back at the Adafruit, maker, science, technology and engineering world

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1880 – Thomas Edison observes the Edison effect or Thermionic emission.

The effect was rediscovered again by Thomas Edison on February 13, 1880, while trying to discover the reason for breakage of lamp filaments and uneven blackening (darkest near the positive terminal of the filament) of the bulbs in his incandescent lamps.

Edison built several experimental lamp bulbs with an extra wire, metal plate, or foil inside the bulb that was separate from the filament and thus could serve as an electrode. He connected a galvanometer, a device used to measure current (the flow of charge), to the output of the extra metal electrode. If the foil was put at a negative potential relative to the filament, there was no measurable current between the filament and the foil. When the foil was raised to a positive potential relative to the filament, there could be a significant current between the filament through the vacuum to the foil if the filament was heated sufficiently (by its own external power source).

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1914 – The American Society of Composers, Authors and Publishers is formed.

The American Society of Composers, Authors, and Publishers (ASCAP /ˈæskæp/) is an American not-for-profit performance-rights organization (PRO) that protects its members’ musical copyrights by monitoring public performances of their music, whether via a broadcast or live performance, and compensating them accordingly.[1]

ASCAP collects licensing fees from users of music created by ASCAP members, then distributes them back to its members as royalties. In effect, the arrangement is the product of a compromise: when a song is played, the user does not have to pay the copyright holder directly, nor does the music creator have to bill a radio station for use of a song.

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1945 – British biologist Marian Dawkins is born.

Dawkins has written extensively on animal behaviour and issues of animal welfare. Along with other academics in the field, such as Ian Duncan,[8] Dawkins promoted the argument that animal welfare is about the feelings of animals.[9] This approach indicates the belief that animals should be considered as sentient beings. Dawkins wrote, “Let us not mince words: Animal welfare involves the subjective feelings of animals.

In 1989, Dawkins published a study in which she filmed hens from above while they performed common behaviours (e.g. turning, standing, wing-stretching). From these films, she calculated the amount of floor-space required by the hens during these behaviours and compared this to the amount of floor-space available in battery cages. She was able to show that many of these common behaviours were highly restricted, or prevented, in battery cages.

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1960 – Black college students stage the first of the Nashville sit-ins at three lunch counters in Nashville, Tennessee.

The Nashville sit-ins, which lasted from February 13 to May 10, 1960, were part of a nonviolent direct action campaign to end racial segregation at lunch counters in downtown Nashville, Tennessee. The sit-in campaign, coordinated by the Nashville Student Movement and Nashville Christian Leadership Council, was notable for its early success and emphasis on disciplined nonviolence. It was part of a broader sit-in movement that spread across the Southern United States in the wake of the Greensboro sit-ins in North Carolina.

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2004 – The Harvard–Smithsonian Center for Astrophysics announces the discovery of the universe’s largest known diamond, white dwarf star BPM 37093. Astronomers named this star “Lucy” after The Beatles’ song “Lucy in the Sky with Diamonds”.

BPM 37093 (V886 Centauri) is a variable white dwarf star of the DAV, or ZZ Ceti, type, with a hydrogen atmosphere and an unusually high mass of approximately 1.1 times the Sun’s. It is about 50 light-years from Earth, in the constellation Centaurus, and vibrates; these pulsations cause its luminosity to vary. Like other white dwarfs, BPM 37093 is thought to be composed primarily of carbon and oxygen, which are created by thermonuclear fusion of helium nuclei in the triple-alpha process.

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2012 – The first ever World Radio Day is held.

Following a request from the Spanish Radio Academy, on 20 September 2010 Spain proposed that the UNESCO Executive Board include an agenda item on the proclamation of a World Radio Day. UNESCO’s Executive Board approved the agenda item in its provisional agenda, for the proclamation of a “World Radio Day” on 29 September 2011. UNESCO carried out a wide consultation in 2011 with diverse stakeholders, i.e. broadcasting associations; public, state, private, community and international broadcasters; UN agencies; funds and programmes; topic-related NGOs; academia; foundations and bilateral development agencies; as well as UNESCO Permanent Delegations and National Commissions for UNESCO. Among the answers, 91% were in favour of the project, including official support from the Arab States Broadcasting Union (ASBU), the Asia-Pacific Broadcasting Union (ABU), the African Union of Broadcasting (AUB), the Caribbean Broadcasting Union (CBU), the European Broadcasting Union (EBU), the International Association of Broadcasting (IAB), the North American Broadcasters Association (NABA), the Organización de Telecomunicaciones Ibeoramericanas (OTI), BBC, URTI, Vatican Radio, etc. The results of this consultation are available in UNESCO’s document 187 EX/13.

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