Henize2-111 & Alpha Centauri
Copyright: Marco Lorenzi
Blazing brightly in the southern sky, the supergiant binary Alpha Centauri is the host of an expansive starscape sprinkled with numerous deep sky objects in this telescopic view.
The most visually striking of its retinue of glittering jewels is the exotic and unique planetary nebula Hen 2-111, which is one of 468 planetary nebulae that were catalogued by Karl Henize in 1967. The main central part of Hen 2-111 is a bright peanut shaped core that measures only 29 x 15 arcseconds.
However, its most visually striking aspect is a faint giant ionized halo that spans 10 x 5 arcminutes! This extreme structure was discovered by B. Louise Webster in 1978 in deep photographic plates taken with the (at the time) Anglo-Australian Observatory. Also barely visible in the glare of Alpha Centauri is a round broken roughly circular shell, which can be seen to the north of the halfway point between Alpha Centauri and Hen 2-111.
This is the supernova remnant G315.4-0.3, which was discovered in a radio continuum survey by Anne Green in 1974 and identified as a supernova remnant in 1975. However, its extremely dim optical shell was discovered recently in 2011 in a search for new supernova remnants in SuperCOSMOS Ha Survey (SHS) images by Milorad Stupar and Quentin Parker.