The Gould's Belt Distances Survey (GOBELINS) III. The distance to the
  Serpens/Aquila Molecular Complex
  We report on new distances and proper motions to seven stars across the
Serpens/Aquila complex. The observations were obtained as part of the Gould's
Belt Distances Survey (GOBELINS) project between September 2013 and April 2016
with the Very Long Baseline Array (VLBA). One of our targets is the
proto-Herbig AeBe object EC 95, which is a binary system embedded in the
Serpens Core. For this system, we combined the GOBELINS observations with
previous VLBA data to cover a total period of ~8 years, and derive the orbital
elements and an updated source distance. The individual distances to sources in
the complex are fully consistent with each other, and the mean value
corresponds to a distance of $436.0\pm9.2$~pc for the Serpens/W40 complex.
Given this new evidence, we argue that Serpens Main, W40 and Serpens South are
physically associated and form a single cloud structure.
