Sunday, January 21, 2007

20070120 - Daytime Crescent paired with Venus

Session name: 20070120.1310

I stole away at lunch yesterday with Tak backpack to look for the young crescent moon. At this time she's already 1 day 14 hours past New Moon. Initially I thought this was to be a cinch. Since I am surrounded by buildings that rise, in some cases, to 60° ~ 70° in elevation, I went first to Cop Cot and then settled at Drip Rock. Since I couldn't see it naked eye I thought that the buildings were obstructing the view.

The Sun's apparent path across the northerner's winter sky is low, and so the ecliptic too is low. Shadows mute most of the cross streets and avenues can suffer the same. The Sun just can't peek high enough to shine his glory down.

I measured off from Sun with outstretched hand and then scan the sky with the handheld bins. In the handheld bins spotted the young crescent pretty quickly and was surprised by the low contrast. I would have thought the 3.3% illuminated crescent to be brighter and greater contrast with the sky. It was darker than passing clouds and in a queer sort of way provided contrast that kept it visible with thin filaments of clouds passing over.

In the field of view, Venus sat up around two o'clock and the Moon was around eight o'clock and LARGE. In spite of its size, its brightness did not contrast sharply with the pale bluish white background sky. On top of the clouds were passing through at as regular clip, sometimes thick enough to snuff out Venus.

As I observed, I couldn't help but think of those record holders who observe crescents as young as 15 hours - even younger! I'm under the impression that these sightings didn't have the advantage of having a bright planet nearby as a convenient landmark. One has to have this kind of experience where one can scan a field of view and allow the eye to find and focus across the field of view, just as repeated tennis lessons develop muscle memory. I looked away on occasion just so I would have to recover it - a kind of volley.

Two passersby took turns at the eyepieces of the Tak bins. I described what they would be looking for and each said after some time of closing one eye, moving their head about, squinting with both eyes that they saw the Moon. I had a feeling it was Venus because that is much brighter, and once resolved easiest to see in the field of view. I suggested that they look for a large, low contrast crescent on the other side. Soon enough they got it. They hadn't a previous mental experience to identify the crescent moon. They were both both shocked by its faintness and large size. Each had found it with a Eureka! feeling.

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