Celestial-sphere sentence example
- The line of the equinoxes is the imaginary diameter of the celestial sphere which joins them.
- The ecliptic itself is the great circle in which this plane meets the celestial sphere.
- It is also defined, but not with absolute rigour, as the apparent path described by the sun around the celestial sphere as the earth performs its.
- The conception of the co-ordinates we have defined is facilitated by introducing that of the celestial sphere.
- Taking as origin the position of an observer, the direction of a heavenly body is defined by the point in which he sees it in the sky; that is to say, on the celestial sphere.Advertisement
- This line, extended upwards, meets the celestial sphere in the zenith.
- As the earth revolves from west to east the celestial sphere appears to us to revolve in the opposite direction, turning on the line j oining the Celestial Poles as on a pivot.
- I, the initial line OX is defined as directed toward the vernal equinox, at which point it intersects the celestial sphere.
- We determine the apparent position of an object near the pole on the celestial sphere at any moment, and again at another moment, twelve hours later, when, by the diurnal motion, it has made half a revolution.
- The equinoxes are the two points on the celestial sphere where the ecliptic intersects the celestial equator.Advertisement
- The earth's axis projected on to the celestial sphere defines astronomical north.
- Zones similar to those already drawn out for the celestial sphere were first introduced by the Pythagoreans.
- In astronomy, we are principally concerned with the orientation of points on a sphere - the so-called celestial sphere - with regard to certain planes and points within the sphere; this subject is treated in the article Astronomy (Spherical).
- But on the celestial sphere the great circles of these two planes are coincident, so that this distinction is not necessary (see Astronomy: Spherical).
- The earth 's axis projected on to the celestial sphere defines astronomical north.Advertisement