Technical implementation of the DESTINY mission concept

Abstract

The Dark Energy Space Telescope (DESTINY) is a proposed approach to the Joint Dark Energy Mission (JDEM). This paper describes its current design and trades of an on-going mission concept study. The DESTINY ~1.8-meter near-infrared (NIR) grism-mode space telescope would gather a census of type Ia and type II supernovae (SN) over the redshift range 0.5<Z<1.7 for characterizing the nature of dark energy. The central concept is a wide-field, all-grism NIR survey camera. Grism spectra with 2-pixel resolving power λ/Δλ≈ 100 will provide broadband spectrophotometry, redshifts, SN classification, as well as valuable time-resolved diagnostic data for understanding the SN explosion physics. DESTINY provides simultaneous spectroscopy on each object within the wide field-of-view sampled by a large focal plane array. The design combines the wide FOV coverage of a flat field, all-reflective three mirror anastigmat with spectroscopy using an optimized nonobjective "objective" grism located in the real exit pupil of the TMA. The spectra from objects within the resulting 0.25 square-degree FOV are sampled with 100 mas pixels by an 8k x 32k HgCdTe FPA. This methodology requires only a single mode of operation, a single detector technology, and a single instrument.