Search results
Results from the WOW.Com Content Network
The velocity structure of the Earth. The red line is the P-wave velocity, the blue line is the S-wave velocity, and the green line density. (Data was adopted from the RockHound Python library.) Seismic velocity structure is the distribution and variation of seismic wave speeds within Earth's and other planetary bodies' subsurface.
A zero-velocity surface is a concept that relates to the N-body problem of gravity. It represents a surface a body of given energy cannot cross, since it would have zero velocity on the surface. It represents a surface a body of given energy cannot cross, since it would have zero velocity on the surface.
Where f is specific force, is angular rate, a is acceleration, R is position, ˙ and V are velocity, is the angular velocity of the earth, g is the acceleration due to gravity, , and h are the NED location parameters. Also, super/subscripts of E, I and B are representing variables in the Earth centered, inertial or body reference frame ...
A satellite ground track may be thought of as a path along the Earth's surface that traces the movement of an imaginary line between the satellite and the center of the Earth. In other words, the ground track is the set of points at which the satellite will pass directly overhead, or cross the zenith, in the frame of reference of a ground observer.
For example, as the Earth's rotational velocity is 465 m/s at the equator, a rocket launched tangentially from the Earth's equator to the east requires an initial velocity of about 10.735 km/s relative to the moving surface at the point of launch to escape whereas a rocket launched tangentially from the Earth's equator to the west requires an ...
The angular velocity of the Earth is defined to be ω = 72.921 15 × 10 −6 rad/s. [ 11 ] This leads to several computed parameters such as the polar semi-minor axis b which equals a × (1 − f ) = 6 356 752 .3142 m , and the first eccentricity squared, e 2 = 6.694 379 990 14 × 10 −3 .
Due to the very slow pole motion of the Earth, the Celestial Ephemeris Pole (CEP, or celestial pole) does not stay still on the surface of the Earth.The Celestial Ephemeris Pole is calculated from observation data, and is averaged, so it differs from the instantaneous rotation axis by quasi-diurnal terms, which are as small as under 0.01" (see [6]).
Difference in longitude of the points on the auxiliary sphere; α 1, α 2: forward azimuths at the points; α: forward azimuth of the geodesic at the equator, if it were extended that far; s: ellipsoidal distance between the two points; σ: angular separation between points: σ 1: angular separation between the point and the equator: σ m