Exit Help
## 3D ORBIT VIEWER

Help File

HELP. Displays this help screen. To exit, click one of the
Exit Help buttons
located at the top and bottom of this screen.
PERICENTER DISTANCE. This parameter defines the distance between
the point in the orbit that is closest to the body whose force determines
the orbit, and the body itself. This distance is measured in
Astronomical Units (AU). One AU is the mean distance from the Earth to
the Sun.
SEMIMAJOR AXIS. This parameter is defined as half the length of the
maximum dimension of an ellipse. This is measured in Astronomical Units
(AU).
ECCENTRICITY. This parameter is a dimensionless number that ranges
from 0 to 1. It is a measure of how much an ellipse deviates from a
circle, whose eccentricity is 0. An ellipse with an eccentricity of 1
would essentially be a straight line with a length equal to the twice the
semimajor axis of the ellipse.
INCLINATION. This parameter is only used in 3-D space and it specifies
how much the 3-D orbit is inclined out of the reference plane, this is measured
in degrees. In situations dealing with the Sun, the reference plane is
the ecliptic. In 2-D, the orbit lies in the reference plane and, therefore,
the inclination is 0 degrees. Inclination can have a value from -360 to 360
degrees.
LONGITUDE OF NODES. This parameter is only used in 3-D space. A
node is the position in the orbit where the plane of the orbit crosses
the reference plane. The Longitude of Nodes is measured from a reference
point to the Ascending Node. The Ascending Node is the node where the
orbit crosses the reference plane heading north.
ARGUMENT OF PERICENTER.
LONGITUDE OF PERICENTER. In 2-D, the longitude of pericenter is the
angle measured from a reference point to the pericenter of the orbit with
the Sun being the vertex of the angle. In 3-D, the longitude of
pericenter is the angle previously mentioned plus the angle of the
ascending node which is measured from the same reference point, also
having the Sun as the vertex of the angle.
TRUE ANOMALY. This parameter specifies the angle between
pericenter (the place along the planet's orbit where the planet-Sun
distance is smallest) and the starting position of the planet along
its orbit. The valid range is 0 to 360 degrees.
ECCENTRIC ANOMALY. The Eccentric Anomaly is used to describe the
variable length of the radius vector **r**. The relationship between
the eccentric anomaly (E) and **r** can be seen through the following
equation: **r**=a(1-e cos E), where a is the semi-major axis and e is
the eccentricity of the ellipse.
MEAN ANOMALY. The mean anomaly is the angle formed between a line
drawn from the Sun to the pericenter of the ellipse and a line from the
Sun to a hypothetical object that has the same orbital period as the real
object being studied, but has a constant angular speed.
TRUE LATITUDE.
MEAN LATITUDE.
TRUE LONGITUDE.
MEAN LONGITUDE.

SUBMIT FORM. Send the parameters that you have chosen to the
orbital viewer program!

Exit Help