Band of very faint light in the night sky. It is thought to be sunlight reflected from interplanetary dust grains lying mostly in the plane of the zodiac, or ecliptic. Seen in the west after twilight and in the east before dawn, it is most clearly visible in the tropics, where the ecliptic is approximately perpendicular to the horizon. In midnorthern latitudes it is best seen evenings in February and March and mornings in September and October (vice versa in midsouthern latitudes). The light can be followed visually to a point about 90° from the Sun. It continues to the region opposite the Sun, where a slight enhancement, the gegenschein, is visible.
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Distance traveled by light moving in a vacuum in one year, at its accepted speed of 186,282 mi/second (299,792 km/second). It equals about 5.9 trillion mi (9.5 trillion km), 63,240 astronomical units, or 0.307 parsec.
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Semiconductor diode that produces visible or infrared light when subjected to an electric current, as a result of electroluminescence. Visible-light LEDs are used in many electronic devices as indicator lamps (e.g., an on/off indicator) and, when arranged in a matrix, to spell out letters or numbers on alphanumeric displays. Infrared LEDs are used in optoelectronics (e.g., in auto-focus cameras and television remote controls) and as light sources in some long-range fibre-optic communications systems. LEDs are formed by the so-called III-V compound semiconductors related to gallium arsenide. They consume little power and are long-lasting and inexpensive.
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That portion of the electromagnetic spectrum visible to the human eye. It ranges from the red end to the violet end of the spectrum, with wavelengths from 700 to 400 nanometres and frequencies from 4.3 × 1014 to 7.5 × 1014 Hz. Like all electromagnetic radiation, it travels through empty space at a speed of about 186,000 mi/sec (300,000 km/sec). In the mid-19th century, light was described by James Clerk Maxwell in terms of electromagnetic waves, but 20th-century physicists showed that it exhibits properties of particles as well; its carrier particle is the photon. Light is the basis for the sense of sight and for the perception of colour. Seealso optics; wave-particle duality.
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Visible is billed as a not-for-profit, free, quarterly magazine dedicated to the history of the lesbian, gay, bisexual, and transgender community. See also LGBT history.
The first issue was scheduled for December 2005 but due to delays in funding the magazine has not been published yet. Although an electronic version was planned through a dedicated website, the official website domain the website points to the website of Design for Diversity.
Tony Malone, Publisher.
Tony is a graphic designer and typographer specialising in accessibility and diversity in design. He is a founding partner of the design consultancy Marsh and Malone He is a member of the steering committee of the LGBT History Month(UK) as artistic director.
Nicolas Chinardet, Editor.
Nicolas was born and bred in France. He moved to London in 2000. He has been a member of the London Gay Men’s Chorus since 2002 and is currently one of its directors and trustees (in charge of Marketing and PR). He is a founding member and the moderator of the London Gay Reading Group He is co-chair of the Southwark LGBT Network
The editorial team are volunteer contributors.