Catching Element Formation In The Act ; The Case for a New MeV Gamma-Ray Mission: Radionuclide Astronomy in the 2020s

Gamma-ray astronomy explores the most energetic photons in nature to address some of the most pressing puzzles in contemporary astrophysics. The unique information provided by MeV gamma-ray astronomy to help address frontiers makes now a compelling time for the community to advocate for a new mission to be operational in the 2020s and beyond.