Search results
Results From The WOW.Com Content Network
For precise applications, many coordinate systems have been defined for the Moon, each with a slightly different prime meridian. The IAU recommends the "mean Earth/polar axis" system, [ 1 ] in which the prime meridian is the average direction (from the Moon's center) of the Earth's center.
The book covers topics such as time, coordinate systems, the Sun, planetary systems, binary stars, the Moon and eclipses. [1] The third edition features new sections on generalised coordinate transformations, nutation, aberration, and selenographic coordinates. The fourth edition, coauthored by Jonathan Zwart, adds "or Spreadsheet" to the end ...
In 1750, Johann Meyer produced the first reliable set of lunar coordinates that permitted astronomers to locate lunar features. [ citation needed ] Lunar mapping became systematic in 1779 when Johann Schröter began meticulous observation and measurement of lunar topography .
Language links are at the top of the page across from the title.
Lunar nearside with major maria and craters labeled. Lunar maria (singular mare) are large, dark, regions of the Moon.They do not contain any water, but are believed to have been formed from molten rock from the Moon's mantle coming out onto the surface of the Moon.
Lunar north polar region mosaic by LRO.The north pole is in the center. The lunar north pole is the point in the Northern Hemisphere of the Moon where the lunar axis of rotation meets its surface.
A planetary coordinate system (also referred to as planetographic, planetodetic, or planetocentric) [1] [2] is a generalization of the geographic, geodetic, and the geocentric coordinate systems for planets other than Earth. Similar coordinate systems are defined for other solid celestial bodies, such as in the selenographic coordinates for the ...
Finding Greenwich time while at sea using a lunar distance. The lunar distance is the angle between the Moon and a star (or the Sun). In the above illustration the star Regulus is used.