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Ursa Astronomical Association
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Ursa Astronomical Association

Humboldtianumin allas - 3.4.2022 at 21.00 - 3.4.2022 at 21.10 Vantaa, Pähkinärinne Observation number 105996

Visibility II / V

Paula Wirtanen, Ursa (Helsinki)

The narrow crescent moon was quite invitingly visible in the courtyard. The weather was almost clear and yes the Moon was quite visible most of the time. But some kind of thin cloud seemed to be a nuisance. Still considering the shallowness of the sickle, it is no wonder that not much detail was distinguished.

However, in my time I admired the Moon so narrow and recognized the familiar craters. Gauss, Hahn, and Berosus stood out, but not as strange bumps. When I switched to a larger magnification, the telescope didn't really show anything at all: now the transparency and seeing would be pretty poor and I was thinking about the rationality of the whole observation thing tonight.

However, the Mare Humboildtianum was visible (without being able to even theoretically mess with the Endymion because it was still in the shadows waiting for sunrise) and yet separated the pool structures around it, I made a simple sketch of its visibility. Really simple, however, because the amount of detail now didn’t get to celebrate.

However, the mare area itself was somehow separated, as were the edges of the pool. They were not exactly seen, but were mostly seen as outlines, with light coming from a great direction to be seen. The crater that separates the inner edge of the lunar sickle is Endymion B.

As a nice additional information, it should be mentioned that Johannes Hevelius had named Mare Humboldtianum Palus Amadoca in his own monthly map. On Riccioli's map, it was called Zoroaster.

The sea named after Alexander von Humboldt became on Mädler's monthly map and that name was then formalized in 1935.

For the sake of certainty, I also took a photo of the area, but it doesn't differ much from that when the weather is what it is. This will have to be tried again in better conditions sometimes.

#Lunar100: 070

Additional information
  • Observation target
    • Moon surface feature
  • Name of the observation target
    • Humboldtianumin allas
  • Seeing
    • Mediocre
Technical information

M127 / 1500 & 25 mm.

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