Ordinary meteors, in the region of the earth's orbit, appear to be separated by intervals of about 250 m.
Encke, the astronomer who first investigated its orbit and showed its periodicity.
It is now known to correspond to the actual orbit of the planet round the sun.
Another element is the time of revolution of the body in its orbit, called its period.
If a point be in motion in any orbit and with any velocity, and if, at each instant, a line be drawn from a fixed point parallel and equal to the velocity of the moving point at that instant, the extremities of these lines will lie on a curve called the hodograph.
Two elements define the position of the plane passing through the attracting centre in which the orbit lies.
We begin by considering the laws of motion in the orbit itself, regardless of the position of the latter.
This, and the inclination of the orbit being given, we have all the geometrical data necessary to compute the coordinates of the planet itself.
As the entire time required for light to pass over the radius of the earth's orbit is only about 500 seconds, this error is fatal to the method.
The plane of the joint orbit, in which no deviation from circularity has yet been detected, nearly coincides with the line of sight.
In astronomy the word denotes the angular distance of a body from the pericentre of the orbit in which it is moving.
The facial portion of the skull is generally shorter than the cranial; the orbit is freely open behind; and the premaxillae tend to be reduced and fused with the nasals.
The problem of determining an orbit may be regarded as coeval with Hipparchus, who, it is supposed, found the moving positions of the apogee and perigee of the moon's orbit.
Orbit in higher forms closed by bone; and ridges of lower cheek-teeth terminating in large loops.
We must conceive a time when the sun was swollen to such an extent that it filled up the entire space girdled by the orbit of Mercury.
The other element is the inclination of the plane of the orbit to the fundamental plane, called the inclination simply.
A sixth is the position of the planet in the orbit at a given moment, for which may be substituted the moment at which it passed the pericentre.
The skull is elongated, with the orbit not separated from the temporal fossa and the nasals, which may or may not carry horns, reaching at least as far forwards as the union of the premaxillae.
After the satellite reached the apogee, it continued in orbit, becoming closer to the center of Earth.
If the consolidation took place with comparative uniformity we might then anticipate the formation of a vast multitude of small planets such as those we actually do find in the region between the orbit of Mars and that of Jupiter.
The combined mass of the earth and moon admits of being determined by its effect in changing the position of the plane of the orbit of Venus.
She contemplated an alliance with Spain, a state quite outside the orbit of Sweden's influence, the firstfruits of which were to have been an invasion of Portugal.
I too would fain be a track-repairer somewhere in the orbit of the earth.