Go to the Select menu, and select Transform Selection. You can then edit the selection by dragging top & bottom or side edges of the bounding box to size the shape any way you want.
It allows you to make selections in the form of various ovals and circles. By default it is free form ovals but hold shift while you make the selection and it will do a perfect circle.
They are not perfect spheres. If they were, they would have been called spherical, not elliptical!
earth
Mars has the most elliptical orbit. The earth's is almost a perfect circle
Variable, as an ellipse is not a perfect circle.
painters
Yes, every orbit is slightly elliptical ... see - nothings perfect!
A circle is an ellipse, so it's elliptical either way.However, the orbit of Mars is not a perfect circle.
About the same shape as an egg, or oblong. Not a perfect circle.
It's an orbit that is not a perfect circle, it has some elongation to it.
Nothing is perfect.
Oval or elliptical shaped. (Not a perfect circle)