- #1
mattrix
- 14
- 2
Can someone please help me with this?
Epoch J2000.0 refers coordinate systems to the mean equinox and mean ecliptic of January 1, 2000, noon TT.
I have the following mean orbital elements for Earth with element date January 1, 2000 and referred to j2000.0 epoch.
a := 1.00000011 - 0.00000005 *cy
e := 0.01671022 - 0.00003804 *cy
p := 102.94719 + 1198.28/3600 *cy
L := 100.46435 + 129597740.63/3600 *cy
i := 0.00005 - 46.94/3600 *cy
O := -11.26064 - 18228.25/3600 *cy
a - semi-major axis
e - eccentricity
p - longitude of perihelion
L - longitude of planet
O - longitude of ascending node, of the intersection of the orbital plane and the plane of the ecliptic
i - inclination, angle between the plane of the ecliptic and the plane of orbit
as I understand it,
the Earth's orbital plane is synonomous with the ecliptic and
as these planes do not intersect the zero direction is taken to be the vernal equinox
I realize that these references move over time, hense epoch.
However I'm confused about how at the time of epoch the last 2 elements can have a value, not equal to zero?
Where is "O" measured from, and to?
I'm not sure about the use of "longitude" either, is this figurative or literal for these 3 elements?
thanks matt
PS does anyone have the Osculating elements for the solar system plants at January 1, 2000.
Epoch J2000.0 refers coordinate systems to the mean equinox and mean ecliptic of January 1, 2000, noon TT.
I have the following mean orbital elements for Earth with element date January 1, 2000 and referred to j2000.0 epoch.
a := 1.00000011 - 0.00000005 *cy
e := 0.01671022 - 0.00003804 *cy
p := 102.94719 + 1198.28/3600 *cy
L := 100.46435 + 129597740.63/3600 *cy
i := 0.00005 - 46.94/3600 *cy
O := -11.26064 - 18228.25/3600 *cy
a - semi-major axis
e - eccentricity
p - longitude of perihelion
L - longitude of planet
O - longitude of ascending node, of the intersection of the orbital plane and the plane of the ecliptic
i - inclination, angle between the plane of the ecliptic and the plane of orbit
as I understand it,
the Earth's orbital plane is synonomous with the ecliptic and
as these planes do not intersect the zero direction is taken to be the vernal equinox
I realize that these references move over time, hense epoch.
However I'm confused about how at the time of epoch the last 2 elements can have a value, not equal to zero?
Where is "O" measured from, and to?
I'm not sure about the use of "longitude" either, is this figurative or literal for these 3 elements?
thanks matt
PS does anyone have the Osculating elements for the solar system plants at January 1, 2000.