Umbra & penumbra

The penumbra (Latin for mid-shadow) is the portion of a shadow that results from the source of illumination being only partially blocked. Penumbras only occur when the source of light is not a point-source. As the sun is a visible disc, solar shadows have penumbras. The penumbra part of a shadow is contrasted with the umbra part of the shadow in which the light source is completely blocked. Image File history File links Umbra & penumbra. ... Image File history File links Umbra & penumbra. ... Latin is an ancient Indo-European language originally spoken in the region around Rome called Latium. ... Shadows on a pavement A shadow is a region of darkness where light is blocked. ... Architect lamps Dark lighting in a concert hall allow laser effects to be visible In the 2005 Classical Spectacular performance, a state-of-the-art lighting system was used to accompany the music Lighting refers to the devices or techniques used for illumination, usually referring to artificial light sources such... For other uses, see Sun (disambiguation). ... A different sense of the word umbra, used in mathematics, is explained in the article titled umbral calculus. ...

The part of the penumbra where an annular eclipse is visible is called the antumbra. For Solar Eclipse, the alien friend of the rubber doll Betty Spaghetty, see Betty Spaghetty Photo taken by John Walker during the Zambia 2001 eclipse A solar eclipse occurs when the Sun, Moon and Earth are on a single line with the Moon in the middle. ... The text or formatting below is generated by a template which has been proposed for deletion. ...

Also, the penumbra is the lighter, fuzzier outer edge of a shadow. The shadow is darkest at the umbra, near the object, and weakest at the penumbra, at the edge.

Other meanings

• The penumbra is also the ring-shaped semi-bright region of a sunspot that surrounds the darker umbra.
• The Penumbra is also a region in the Umbra, the spirit world of the World of Darkness line of role-playing games.
• "Penumbra" is an episode of Star Trek: Deep Space Nine.
• An area in which something exists to a lesser or uncertain degree: "The 4th Amendment has a penumbra where privacy is protected from governmental intrusion.”
• There is a cycle of cards in the game Magic: The Gathering that creates a shadow-like token of itself upon death.

A sunspot is a region on the Suns surface (photosphere) that is marked by a lower temperature than its surroundings and intense magnetic activity, which inhibits convection, forming areas of low surface temperature. ... A different sense of the word umbra, used in mathematics, is explained in the article titled umbral calculus. ... Categories: Stub | World of Darkness | Werewolf: The Apocalypse | Mage: The Ascension ... This articles content is specific to the fictional setting known as the World of Darkness. ... This article does not cite its references or sources. ... The World of Darkness is the name given to two distinct fictional universes developed by White Wolf Game Studio. ... A role-playing game (RPG) is a type of game in which players assume the roles of characters and collaboratively create narratives. ... Penumbra is an episode from the seventh season of Star Trek: Deep Space Nine, the first of the ten final chapters. ... Space station Star Trek: Deep Space Nine (ST:DS9 or STDS9 or DS9 for short) is a science fiction television series produced by Paramount and set in the Star Trek universe. ... Amendment IV (the Fourth Amendment) of the United States Constitution, which is part of the Bill of Rights, guards against unreasonable searches and seizures. ... Magic: The Gathering (colloq. ...

See also

• eclipse