Crater Triesnecker and its Rilles

Sketching: For this sketch I used: black Strathmore 400 Artagain paper, white and black Conte’ pastel pencils and blending stumps, white Pearl eraser. Telescope: 10 inch f/ 5.7 Dobsonian on a drive platform and 6mm and 4mm ortho eyepieces 241x and 361x Date: 8-20-2011 05:00-07:10 UT Temperature: 26° C (77° F) Partly to mostly cloudy, 80% relative humidity Waning gibbous phase Seeing: Antoniadi III Colongitude: 164 ° Lunation: 20.4 days Illumination: 66.3 % Frank McCabe