MONTHLY OBSERVER’S CHALLENGE

Compiled by:

Roger Ivester, North Carolina 

&

Sue French, New York

September 2020

Report #140 

The Veil Nebula has long been modeled as the remnant of a supernova explosion that occurred within an interstellar cavity created by the progenitor star. However, a recent study by Fesen, Weil, and Cisneros (2018MNRAS.481.1786F ) using multi-wavelength emission maps indicates that the large-scale structure of the Veil Nebula is due to interaction of the remnant with local interstellar clouds. Employing Gaia DR2 data, the team determined an distance of 735±25 pc. 

This beautiful nebula bears several NGC designations. Its western arc, NGC 6960, runs through the naked-eye star 52 Cygni and is commonly called the Witch’s Broom. The tantalizingly intricate western arc is called NGC 6992 in the north, while the tattered southern reaches comprise NGC 6995. The brightest part of Pickering’s Triangular Wisp, which claims no NGC number, lies between the northern tips of the two great arcs. The discoverers of NGC 6974 (Lord Rosse) and NGC 6979 (William Herschel) gave these pieces positions that don’t correspond to anything obvious, but the names have been popularly tagged onto the northern and southern parts of the nebulosity just east of Pickering’s Triangular Wisp. As good a guess as any.

September 2020 OBSERVERS CHALLENGE _Veil Nebula