Quote:
Originally Posted by ngcles
Hi Chris & All,
Has anyone been able to "resolve" the crescent shape naked-eye?
Les D
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I mostly doubt it. The maximum size is 1 arcmin (61 arcsec), which is about half the resolution of the naked eye. However, I only once (from about 9 attempts) thought I saw the crescent in the morning eastern sky just before sun-up - on the final day Venus was possibly visible. The eye saw what instead looked like two stars on the opposing cusps, though I could not see the crescent. In binoculars, the crescent was obvious, whose phase was about around 1%. Sadly, I had about one and a bit minutes before in was lost in the general haze caused by the solar rays just reaching the lower atmosphere. I did not earlier see Venus on the western side due to cloud cover and heavy rain (earliest I think was about 3% or 4%). Robert Price when he was in Cootamundra observed the crescent several times too - but the observation was either binoculars or telescopes.
A recommended trick is said to use a purple 35A Wratten filter, which darkens the field and improves contrast. It had something to do with the ultra-violet emission of the upper atmosphere of Venus - but for me it made minor differences. I eventually convinced myself it was simply bull from formal UV observations by one of the old Venus orbiter missions.
I'll dig up my notes and comments tomorrow, and look up my general text of Venus - but for now - I'm off to bed. I've got a drawing in my note book too. (Earlier really a terrible night's observing except for the widest of pairs - mixed with the moonlight. Yucky poo!)
Hope you guys did have some luck spotting the narrow crescent.
NOTE: In the old days I use to do drawings and visual observations of dichotomy for the B.A.A. Mercury and Venus section. Observations were made in daylight on the meridian, which was really punishing in the summer months. The practice of seeing the maximum crescent in daylight was considered to be too dangerous so near the Sun.
Venus (With VERY Skimpy Underwear)
