NavList:

Dear Modris,

Nice to read from you again.

I think you are very close from the true position.

Let me explain how I have come to this conclusion.

From the picture, through an augmented horizontal semi-diameter computed at 16.574' the best I can measure is Limb to top star distance 5.801' and Limb to right star distance 3.315' . Again, such measurements can be made only to +/- 0.05' , and I am probably optimistic here ... I am well aware that the extra digits published do not carry any physical significance here.

As per the SIMBAD star catalog, for the TOP star, I am using Hipparcos 29264 B which is just a few arcseconds from 29364 A, and for the Star to the right I am using Hipparcos HD 283750 which is the same as yours.

I am not using the Moon Center because it is not singled out on the photo. And on top of that it is refracted, while the Moon is not exactly circular. Some significant differential refraction comes to play here, and its effect is quite measurable on the photo.

Starting from your own position , N33°34' / W111°39', I am computing:

- HIP 29264 B refracted distance to refracted limb : 5.886' (vs. 5.801' measured), and:

- HD 283750 / HIP 21482 refracted distance to refracted limb : 3.686' (vs. 3.315' measured).

Given the very small differences between the numbers here-above, your position used for such computations is quite close from the actual true position.

Well done Modris !

Kermit

antoine.m.couette@club-internet.fr