Matches in DBpedia 2016-04 for { <http://wikidata.dbpedia.org/resource/Q1195520> ?p ?o }
Showing triples 1 to 26 of
26
with 100 triples per page.
- Q1195520 subject Q7033720.
- Q1195520 subject Q7144650.
- Q1195520 abstract "Diurnal motion is an astronomical term referring to the apparent daily motion of stars around the Earth, or more precisely around the two celestial poles. It is caused by the Earth's rotation on its axis, so every star apparently moves on a circle, that is called the diurnal circle. The time for one complete rotation is 23 hours, 56 minutes and 4.09 seconds (1 sidereal day). The first experimental demonstration of this motion was undertaken by Léon Foucault.Direction of the motion in the Northern hemisphere: Looking to the north, below the North Star: left-right, west-east Looking to the north, above the North Star: right-left, east-west Looking to the south: left-right, east-westThus northern circumpolar stars move counterclockwise around the North Star.At the North Pole, north, east and west are not applicable, the motion is simply left-right, or looking vertically upward, counterclockwise around the zenith.For the southern hemisphere, interchange north/south and left/right, and replace North Star by southern celestial pole. The circumpolar stars move clockwise around it. East/west are not interchanged.At the equator the two celestial poles are at the horizon and motion is counterclockwise (i.e. to the left) around the North Star and clockwise (i.e. to the right) around the southern celestial pole. All motion is from east to west, except for the two stationary points.The daily path of an object on the celestial sphere, including the possible part below the horizon, has a length proportional to the cosine of the declination. Thus the speed of the diurnal motion of a celestial object is this cosine times 15 °/hr = 15'/min = 15"/s, i.e. (compare angular diameter): Up to a Sun or Moon diameter every two minutes ca. four seconds for the largest planet 2000 diameters of the largest stars per secondDiurnal motion can be seen in stop motion photography. Circumpolar stars close to the celestial pole move only slowly. Conversely, following the diurnal motion with the camera, to eliminate it on the photograph, can best be done with an equatorial mount, which requires adjusting the right ascension only; a telescope may have a motor to do that automatically (sidereal drive).".
- Q1195520 wikiPageWikiLink Q1061971.
- Q1195520 wikiPageWikiLink Q12115.
- Q1195520 wikiPageWikiLink Q12119.
- Q1195520 wikiPageWikiLink Q12134.
- Q1195520 wikiPageWikiLink Q1303849.
- Q1195520 wikiPageWikiLink Q13442.
- Q1195520 wikiPageWikiLink Q16726164.
- Q1195520 wikiPageWikiLink Q187966.
- Q1195520 wikiPageWikiLink Q191747.
- Q1195520 wikiPageWikiLink Q2.
- Q1195520 wikiPageWikiLink Q23538.
- Q1195520 wikiPageWikiLink Q308876.
- Q1195520 wikiPageWikiLink Q333.
- Q1195520 wikiPageWikiLink Q4213.
- Q1195520 wikiPageWikiLink Q523.
- Q1195520 wikiPageWikiLink Q662656.
- Q1195520 wikiPageWikiLink Q7033720.
- Q1195520 wikiPageWikiLink Q7144650.
- Q1195520 wikiPageWikiLink Q76287.
- Q1195520 wikiPageWikiLink Q79782.
- Q1195520 wikiPageWikiLink Q82806.
- Q1195520 comment "Diurnal motion is an astronomical term referring to the apparent daily motion of stars around the Earth, or more precisely around the two celestial poles. It is caused by the Earth's rotation on its axis, so every star apparently moves on a circle, that is called the diurnal circle. The time for one complete rotation is 23 hours, 56 minutes and 4.09 seconds (1 sidereal day).".
- Q1195520 label "Diurnal motion".