Tuesday, 15 March 2016

Oblique impact: Schiller


Is Schiller the best example of an oblique impact event anywhere in the solar system? Maybe. At 180km long it's an impressive sight. Gault and co-workers found in the 1970's that hollow projectiles could cause elongated complex 'divots' like this. Likely the 'object' was pretty irregular - based on recent views of asteroids and comet nucleii: and perhaps ~10km on one dimension. And impacted at an angle of <5 degrees. This C8 eyepiece log was rendered in ink-wash: slow, but rewarding!

Friday, 4 March 2016

Stellar Sensation NGC2516

Among my favourite groups: an NGC cluster and a larger star grouping produce a sensational 'vista'. Telescope users can miss it by using high powers. NGC2516 is the dense swarm of blue (type B) stars and maybe a couple of redder ones in the lower part of this sketch - with some wonderful 'tight' multiples in this cluster - hinted at in the sketch. It just happens that a larger, maybe closer, aggregation of  brighter stars provides a colourful setting for the small cluster. It was sketched with an old 4" Mak' in a big city. At my new darker site it never fails to delight : the most colourful field I know of! Other suggestions? In the 10"f5 a 32 e.p. gives the richest view. As the scale shows - its a wide field. Look at the 'foot' of the 'False Cross' in Carina.