# How to estimate the inclination of a galaxy between edge on and face on?

I have the images of a galaxy and the field of view and I would like to determinte the inclination of a galaxy between edge-on and face-on. Would that information be enough to do the calculation? Or what other details would be needed?

• Possibly more than you've provided in this question... Details are required. – ProfRob Apr 7 at 22:21
• I have the images of a galaxy and the field of view. Would that be enough to do the calculation? Or what other details would be needed? – andi Apr 7 at 23:57
• @andi Welcome to astronomy SE. I included your comment to your question, and as far I as I can tell, it looks like a valid question, so I voted to keep it open. – B--rian Apr 8 at 7:11

If we define $$0^\circ$$ to be face-on, then when tilted at an angle $$i$$ away from face-on, the shorter axis will appear to be decreased in length by a factor of $$\cos i$$. Thus, assuming that the galaxy is circular in cross-section, you can determine its inclination from $$\cos i = \frac{\rm short\ axis}{\rm long\ axis}$$.