This paper describes the current status of the technical program aiming to demonstrate the viability of a formation-flying mid-infrared nulling interferometer architecture for the Terrestrial Planet Finder (TPF) program. Until recently the TPF project was considering four architectures, with the goal of selecting one in the 2006 timeframe. In April 2004, the project office opted instead to follow a path leading to a small (4x6m) visible-light coronagraph, to launch around 2014, and a formation-flying interferometer (FFI), to launch before 2020. The FFI is proposed to satisfy the full TPF science goal to completely survey 150 stars for evidence of terrestrial planets similar to Earth, while the coronagraph will perform a survey of 30-50 stars at visible wavelength. FFI trade studies conducted since mid-2003 have focused on key factors driving overall flight segment mass and performance, including launch vehicle packaging, deployment approach, thermal design (particularly the thermal shield configuration), structural design, and formation flying approach. This paper summarizes the results of the recent design trades, with discussion of the primary requirements that drive the baseline design concept. Analyses supporting the baseline design are summarized, and areas for future study are discussed.
The Cold Interferometric Nulling Demonstration in Space (CINDIS) is a modest-cost technology demonstration mission, in support of interferometer architectures for Terrestrial Planet Finder (TPF). It is designed to provide as complete as possible a demonstration of the key technologies needed for a TPF interferometer at low risk, for a cost less than $300M. CINDIS foregoes scientific objectives at the outset, enabling significant cost savings that allow us to demonstrate important features of a TPF interferometer, such as high-contrast nulling interferometry at 10 μm wavelength, vibration control strategies, instrument pointing and path control, stray light control, and possibly 4-aperture compound nulling.
This concept was developed in response to the NASA Extra-Solar Planets Advanced Concepts NRA (NRA-01-OSS-04); this paper presents the results of the first phase of the study.