FIG. 2.

Schematic representation of the Milky Way Galaxy. The Sun is indicated by the cross. The galactic habitable zone is indicated by the dashed, gray circles, based on work of Gowanlock et al. (2011). The approximate galactic positions of the molecular clouds where formamide has been detected are indicated by filled circles. The circle size indicates the relative amount of formamide. The figure summarizes the current work and past observations (e.g., Cummins et al., 1986; Bisschop et al., 2007; Halfen et al., 2011). The distances are in kiloparsecs, or kpc (1 kpc ∼ 3259 light-years).