#### Marijn

##### Active member

Perhaps someone has already figured this out and could help me with this.

The example below is the (simplified) html for asteroid Ryugu. I am trying to calculate the numbers for drawing the ellipse based on the orbital elements as displayed below the diagram on the Asterank home page.

The semi-major axis, a, is given. The semi-minor axis b can be calculated using e. These numbers need to be multiplied by 50 (pixels) in order to get the values as in the example below.

W is used for the first param of the transform function.

So I am close. But I do not understand how cy is calculated. Also, I need to fit the inclination in somehow.

Can anybody help me to complete this calculation?

svg width="300" height="170"

ellipse rx="58.39395781893142"

ry="59.48004109924875"

cx="150"

cy="86.31463562865277"

transform="rotate(211.4258497031505, 150, 75)"