  For the first time in human history, technologies have matured sufficiently
to enable a mission capable of discovering and characterizing habitable planets
like Earth orbiting sunlike stars other than the Sun. At the same time, such a
platform would enable unique science not possible from ground-based facilities.
This science is broad and exciting, ranging from new investigations of our own
solar system to a full range of astrophysics disciplines.
  The Habitable Exoplanet Observatory, or HabEx, is one of four studies
currently being undertaken by NASA in preparation for the 2020 Astrophysics
Decadal Survey. HabEx has been designed to be the Great Observatory of the
2030s, with community involvement through a competed and funded Guest Observer
(GO) program. This interim report describes the HabEx baseline concept, which
is a space-based 4-meter diameter telescope mission concept with ultraviolet
(UV), optical, and near-infrared (near-IR) imaging and spectroscopy
capabilities.
  More information on HabEx can be found at https://www.jpl.nasa.gov/habex
