in the astronomy is the scan time the time, in which a heavenly body full-leads a complete orbiting to its point of reference. Here it is to be noted that there can be several points of reference. So can e.g. the scan time of the moon with or without inclusion of the simultaneous movement that Earth around the sun to be indicated. Normally the scan time is indicated against as static a reference system as possible, for which usually the starlit sky serves. Such a scan time is called “siderisch” (relative to the stars).
In addition, the purchase can be (apparent) the sun position (Synodi period), thatKnot of individual planet courses (“drakonitisch”), the emphasis entire solar system or of two its body (baryzentrisch) or the “remainder of the universe “(inertial system) its.
The siderischen scan times of the moon and the planets of our solar system amount to:
Moon: 27,32 days Merkur: 87,97 days Venus: 224,70 daysEarth: 365,256 days (tropical 365.242 days) Mars: 686,98 days (1 year 322 days) Jupiter: 11.869 years (11 years 317 days or 4334 days) Saturn: 29.628 years (29 years 229 days) Uranus: 84.665 years (84 years 243 days) Neptun: 165.49 years (165 years and 5-6Months) Pluto: 247.7 years (247 ½ until 248 years).
Dengegenüber are clearly longer, shorter starting from Jupiter however increasingly the synodischen scan times with moon, Merkur, Venus and Mars (1.092 to 1.004 years).
also technical plants have a rotating running time, e.g. Lichtzeichenanlagen.