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Paolo Palma
Naples - Italy
08/25/2023
11:30 am

Equipment Details:

Dobson telescope 18" - smartphone A51

Post-processing Details:

Collage

Image Details:

Venus crescent roll over

Day after day, straddling its inferior conjunction, it is possible to notice in Venus a rotation of its crescent as partially summarised in these two shots.

If before 13th August the planet was seen to the East of the Sun and its profile tended to narrow as it approached it, after that date it appears to the West of our star and its profile now tends to grow as it moves away from it.

If this change in perspective - to the naked eye - results in the transition from the 'Evening Star' to the 'Morning Star' traditionally also referred to as the Hesperus and Lucifer, to the telescope it results in what is called a 'Venus crescent roll over', because the apparent 'D-shape' it showed in the Decrescent phase has now become 'a C' in the Crescent phase.

The images published here are taken through a dobsonian telescope, so the planet is captured 'upside down' relative to reality, or we could say rotated 180°.

In the descending phase then, Venus really does show the belly of a D; and in the rising phase it takes on the exact shape of a C. Because unlike the Moon, that during a Crescent phase looks like a D and during the Decrescent phase looks like a C, it is NOT a "liar" at all, at least from boreal hemisphere.