From the Latin for shade, it is the shadow area defining a total eclipse. or the dark central region of a sunspot.
The dark core or cores (umbrae) in a SUNSPOT with PENUMBRA, or a sunspot lacking penumbra.
HMS Umbra was a British Ursula Class submarine of 540 tons displacement launched in the early 1940s. She was armed with one small gun and six 21-inch torpedo tubes in the bow. She had a top speed of 11.25 knots surfaced and 10 knots submerged and carried a complement of 27.Found on http://www.probertencyclopaedia.com/browse/RU.HTM
Umbra is a cultivated variety of potato.Found on http://www.probertencyclopaedia.com/browse/QU.HTM
Umbra is a Toronto-based designer and manufacturer of houseware. (The name umbra means shade in Latin). The company was founded by two childhood friends in 1979. The company now sells more than 2,000 home products, sold through 25,000 retailers in 75 countries. The company`s products are recognized by a stylized `U` printed on eac...Found on http://en.wikipedia.org/wiki/Umbra_(company)
(Phytolacca) This group consists of hardy and tender perennials. They are found wild in North and South America, Asia and Africa. Very few kinds are in cultivation. P. dioica, the Umbra, is a quick growing tree that is grown for decoration in mild climates. It is an evergreen and grows up to 60 feet high. It produces white flowers. P. americana, Po...Found on http://www.encyclo.co.uk/local/10004
The dark central region of a sunspot.
Found on http://www.solarviews.com/eng/terms.htm
Latin, meaning: shade, shadow. Found on http://archives.nd.edu/uuu.htm
- a region of complete shadow resulting from total obstruction of lightFound on http://www.webdictionary.co.uk/definition.php?query=umbra
(1). The darkest part of the shadow cast by Earth into space. (2). The darker portion of a sunspot.
Found on http://www.encyclo.co.uk/local/20448
The darkest part of a shadow where no light from the source reaches.Found on http://www.diracdelta.co.uk/science/source/u/m/umbra/source.html
Origin: L, a shadow. ... 1. <astronomy> The conical shadow projected from a planet or satellite, on the side opposite to the sun, within which a spectator could see no portion of the sun's disk; used in contradistinction from penumbra. See Penumbra. The central dark portion, or nucleus, of a sun spot. ... The fainter part of a sun spot; now m...Found on http://www.encyclo.co.uk/local/20973
a region of complete shadow resulting from total obstruction of lightFound on https://www.encyclo.co.uk/local/20974
(um´brә) the part of a shadow in which there is no light from any light source. a sharp appearance to the edges of a structure on a radiograph.Found on http://www.encyclo.co.uk/local/21001
• (n.) The conical shadow projected from a planet or satellite, on the side opposite to the sun, within which a spectator could see no portion of the sun`s disk; -- used in contradistinction from penumbra. See Penumbra. • (n.) The fainter part of a sun spot; -- now more commonly called penumbra. • (n.) The central dark portion, or nu...Found on http://thinkexist.com/dictionary/meaning/umbra/
(from the article `Sun`)Found on http://www.britannica.com/eb/a-z/u/5
that part of a shadow in which all light from a given source is excluded. The shadow from a point source of illumination is essentially all umbra, ... [1 related articles]Found on http://www.britannica.com/eb/a-z/u/5
umbra (s), umbrae (pl) 1. A dark area, especially the blackest part of a shadow caused by light from all points of a source being prevented from reaching the area, usually by an opaque object. 2. In astronomy, the shadow region over an area of the earth where a solar eclipse is total. 3. The darkest region of a sunspot. 4. A shade; su...Found on http://www.wordinfo.info/words/index/info/view_unit/2224/2
Umbra is Latin for shadow.Found on http://www.probertencyclopaedia.com/YS.HTM
• The portion of a shadow cone in which none of the light from an extended light source (ignoring refraction) can be observed. • The dark core or cores in a sunspot with a penumbra, or all of a sunspot that lacks a penumbra. Plural is umbrae.Found on http://www.daviddarling.info/encyclopedia/U/umbra.html
umbra: see eclipse; sunspots.Found on http://www.infoplease.com/ce6/sci/A0919892.html
Umbra is the astrological term for the shadow cast by a planet or satellite.Found on http://www.probertencyclopaedia.com/browse/GU.HTM
Central region of a shadow that is totally dark because no light reaches it, and from which no part of the light source can be seen (compare penumbra). In astronomy, it is a region of the Earth from which a complete eclipse of the Sun can be seenFound on http://www.talktalk.co.uk/reference/encyclopaedia/hutchinson/m0030407.html
the darker, smaller shadow cast by the Moon during a total solar eclipse.Found on http://www.kidseclipse.com/pages/glossary.htm
The name given to the shadow cast by a celestial object that entirely blocks out illumination.Found on http://www.moonconnection.com/moon-glossary.phtml
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