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Updates from the Project Manager
 SIM Lite Project Manager James Marr 8 November 2010
As most know by now, the Astro2010 Decadal Survey (available at http://sites.nationalacademies.org/bpa/BPA_049810) did not recommend SIM Lite for development this decade. The EOS Program Prioritization Panel did recommend SIM Lite as a candidate for consideration in competition with other exoplanet mission concepts at a suggested mid-decade concept consideration opportunity that is yet to be defined in detail.
Given the Astro2010 recommendation, NASA’s Director for Astronomy and Astrophysics, Dr. Jon Morse, sent the project a letter on September 24, 2010 withdrawing NASA sponsorship of SIM Lite and directing the project to discontinue Phase B activities immediately or as soon as practical.
The SIM Lite project is currently in the process of implementing this direction: archiving project information; disposing of testbeds and prototype hardware; and reassigning personnel. These activities will be completed no later than December 31, 2010.
I would like to take this opportunity to thank those in the community who have supported SIM for the past 20 years (or more) and those dedicated engineers and scientists who have dedicated a significant portion of their working careers trying to make SIM a reality. Your support and efforts have been deeply appreciated.
The SIM team has made enormous progress over the past 14 years. These accomplishments include:
- Advancement of all required technologies for micro-arcsecond astrometric measurements to flight readiness;
- Demonstration of flight designs for all major instrument system assemblies, including demonstration of the ability to withstand the rigors of launch and operation over required flight temperature ranges;
- Development of a very mature mission and system design that was ready to proceed to implementation and would have achieved all performance and science recommendations of the 1990 and 2000 Astronomy and Astrophysics Decadal Surveys.
While this will be the last Project Manager’s update, it is anticipated that the SIM Lite website will remain available for external access for at least one year (to December 31, 2011), and quite possibly longer.
The ExoPlanet Exploration Program’s web site, http://exep.jpl.nasa.gov/, and the PlanetQuest web site (http://planetquest.jpl.nasa.gov/) will remain active sites for readers to follow progress in the exploration of extra-solar worlds.
May 25, 2010
Assembly of the brassboard Astrometric Beam Combiner (ABC) continues.
Over the past couple of months, several additional ABC subassemblies were integrated into the ABC Bench: (1) the Fringe Tracker Assembly (FTA), (2) the Fringe Tracker Camera (FTC), and (3) several Fold and Alignment Mirrors & Mechanisms.
Two photos of the partially assembled ABC are shown below.
Two new papers on the synergy of SIM Lite and direct imaging have recently been published on astro-ph. The first of these (http://arxiv.org/abs/1003.4702) discusses the benefit of asrometry to any direct imaging mission and the second (http://arxiv.org/abs/1005.2391) specifically addresses the benefit of astrometry to a mission with JWST with an external occulter.
Seventeen papers on SIM Lite will be presented at the upcoming SPIE Astronomical Instrumentation Conference in San Diego to be held from 6/27/10 to 7/2/2010. Links to these papers will be available on the SIM Lite web site (this site) following the conference.
Copyright 2010 California Institute of Technology. Government sponsorship acknowledged.
March 19, 2010
Assembly of the brassboard Astrometric Beam Combiner (ABC) is now well under way with several subassemblies already integrated into the bench. By the way, a brassboard is form, fit, and function to flight and has been tested to flight qualification levels of vibration (simulating launch) and thermal (simulating the range of temperatures over which the equipment is required to survive).
The figure to the right shows where the ABC fits into the SIM Lite instrument. There is one ABC for each of the two Michelson Stellar Interferometers (MSI) in SIM Lite (the science MSI and the Guide-1 MSI). Each ABC consists of about two-dozen subassemblies. For a description of the ABC and its subassemblies, see Section 20.3 of the 2009 SIM Lite book in Chapter 20: SIM Lite Flight System Design.
Over the past month, two additional ABC subassemblies were delivered: (1) the Fringe Tracker Assembly (FTA) and (2) the Fringe Tracker Camera (FTC). Drawings for these are shown in Figure 20-9 of the 2009 SIM Lite book (link above). Photos of the actual tested and delivered brassboard hardware for these two assemblies appear to the right. Both of these assemblies are now integrated into the ABC bench.
February 19, 2010
For a broad overview of SIM Lite science, science opportunities, technology, construction, and operations, refer to the SIM Lite book at: http://planetquest.jpl.nasa.gov/SIM/keyPubPapers/simBook2009/.
SIM Lite is currently under review by the National Academies’ Astronomy and Astrophysics Decadal Survey (Astro2010), with report release expected in September 2010. This report will make recommendations to NASA regarding priorities for the coming decade (2010 to 2020). At this point in time, it is not clear whether the Survey will in fact rank specific mission concepts or just specific science objectives. Visit the Astro2010 web site, http://sites.nationalacademies.org/bpa/BPA_049810, to track the progress of the Survey.
SIM Lite’s future progress towards launch will depend upon both the Astro2010 Survey recommendations and the ability of NASA’s Astronomy and Astrophysics Division to provide funding. There is also growing interest in SIM Lite within the European community that might eventually lead to European participation in the development of SIM Lite.
While the project waits for the Astro2010 survey results and subsequent direction from NASA, progress continues to be made on reducing instrument risk through building and testing brassboard instrument assemblies. These assemblies match form, fit and function of the SIM Lite flight hardware and are built using standard JPL flight hardware practices. After they are built, these assemblies are subjected to performance testing, then qualification-level environmental testing (vibration and thermal), followed by performance retesting. While a number of these assembly brassboards have been successfully built and tested over the past several years (including the picometer metrology assemblies), the project has just recently (Feb 2010) completed the successful build and test of three optical path control assemblies: the Fine Steering Mechanism (FSM), Modulation Optical Mechanism (MOM), and the Pathlength-control Optical Mechanism (POM). A brassboard Astrometric Beam Combiner (ABC), a large and complex assembly with many subassemblies, is currently under construction with expected completion by May 2010, at which time testing will begin. Descriptions of these assemblies can be found in Chapter 20 of the SIM Lite book located at http://planetquest.jpl.nasa.gov/SIM/keyPubPapers/simBook2009/.
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