ephem: how to get tilt angle of Earth?

Question

I am using python's package ephem.

I can not locate function to get tilt angle between ecliptic plane and equatorial plane.

Hope some one can help me.

score 2 · Answer 1 · answered Jun 10 '16 at 00:21

2

Since 0° right ascension is defined as the point where the equatorial and ecliptic planes cross, they are farthest apart at 90° right ascension, where their distance from each other is the same as the Earth’s tilt on its axis:

from ephem import Equatorial, Ecliptic
p = Equatorial('90', '0', epoch='2000')
print Ecliptic(p).lat

The result is the Earth’s axial tilt at the beginning of the year 2000:

23:26:21.4

answered Jun 10 '16 at 00:21

Brandon Rhodes

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Thanks a lot. Hon-Jang – hjyanghj Jun 13 '16 at 01:05

score -1 · Answer 2 · answered Jun 06 '16 at 13:48

-1

Bit of Googling might give you your answer:

answered Jun 06 '16 at 13:48

Bernmeister

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Thanks. But what I want is: Use function in pyephem to get tilt angle. – hjyanghj Jun 07 '16 at 10:01
Those links I gave you should give enough to be able to calculate it yourself using a mixture of PyEphem and Python...or so I thought if I understand your question. I wanted to calculate the bright limb angle of the moon for a project I did and I used PyEphem for the location of the body (moon and earth) and Python, plus references to astronomical books! – Bernmeister Jun 07 '16 at 10:21

ephem: how to get tilt angle of Earth?

2 Answers2