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Lee Feinberg

Publications and source records attributed to Lee Feinberg.

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2026

The Habitable Worlds Observatory Technology Development Plan

The Habitable Worlds Observatory (HWO) is NASA’s next large space telescope, selected by the 2020 Decadal Survey in Astronomy and Astrophysics to search for and characterize habitable exoplanets while enabling a broad range of transformative astrophysics. In August 2024, the HWO Technology Maturation Project Office (TMPO) was formed to begin exploring the HWO science, technology, and mission architectures toward a Mission Concept Review (MCR) at the end of the decade. A primary deliverable of this effort is this technology development plan that identifies critical technologies that enable the mission, defines a process for assessing the readiness of those technologies, and outlines a strategy for developing those technologies to a Technology Readiness Level (TRL) of 5 before the MCR. This document covers technologies organized along three “tracks”: Coronagraph System technologies, Ultra-stable Telescope System technologies, and High-sensitivity Ultraviolet and Visible Instrumentation technologies. Additional emerging and enhancing technologies are also discussed.

technology development↗
NASA NTRS2022

Phasing the Webb Telescope

The James Webb Space Telescope (JWST) is a segmented deployable telescope, currently operating at L2. The telescope utilizes 6 degrees of freedom for adjustment of the Secondary Mirror (SM) and 7 degrees of freedom for adjustment of each of its 18 segments in the Primary Mirror (PM). After deployment, the PM segments and the SM arrived in their correct optical positions to within a ~1 mm, with accordingly large wavefront errors. A Wavefront Sensing and Controls (WFSC) process was executed to adjust each of these optical elements in order to correct the deployment errors and produce diffraction-limited images across the entire science field. This paper summarizes the application of the WFSC process.

JWST↗
NASA NTRS2015

A Future Large-Aperture UVOIR Space Observatory: Reference Designs

Our joint NASA GSFC/JPL/MSFC/STScI study team has used community-provided science goals to derive mission needs, requirements, and candidate mission architectures for a future large-aperture, non-cryogenic UVOIR space observatory. We describe the feasibility assessment of system thermal and dynamic stability for supporting coronagraphy. The observatory is in a Sun-Earth L2 orbit providing a stable thermal environment and excellent field of regard. Reference designs include a 36-segment 9.2 m aperture telescope that stows within a five meter diameter launch vehicle fairing. Performance needs developed under the study are traceable to a variety of reference designs including options for a monolithic primary mirror.

exo-planets↗
NASA NTRSDate not supplied

The James Webb Space Telescope Mission Status

The James Webb Space Telescope (Webb) is a large, infrared space telescope that recently completed its on-orbit commissioning activities and will now embark on the first year of approved science. Its architecture includes many first-of-its-kind innovations for space, including a segmented primary mirror that is 6.6 m in diameter and a 5-layer sunshield used to passively cool the telescope and its four science instruments. Although Webb had an extensive test program, the system-level performance often relied on predictions based on integrated modeling, using conservative factors for the model uncertainties and primarily focusing on evaluating the performance requirements at end of life. A set of commissioning activities were designed for a system-level characterization of the performance. This proceeding will provide the status of the mission, including a discussion of the major events, on-orbit system performance, and early science highlights.

Michael McElwain↗
NASA NTRSDate not supplied

Building JWST

Explore the source record for details and available documents.

Lee Feinberg↗
NASA NTRSDate not supplied

The Meteoroid Environment Encountered By the James Webb Space Telescope

All spacecraft run the risk of being damaged by meteoroids at a rate proportional to the spacecraft's surface area. The exceptionally large James Webb Space Telescope (JWST) has endured 20 impacts on its primary mirror in its first year of operation. While most of the impacts experienced were commensurate with pre-launch predictions, one particularly large impact in May 2022 prompted the program to take a fresh look at the meteoroid environment in order to determine whether potentially unaccounted-for meteoroid risks can be mitigated. In this talk, we present a directional model of the meteoroid environment encountered by the spacecraft and compare it with the observed impact rate. Because of JWST’s ability to measure nanometer-size changes to the primary mirror surface, our results indicate that meteoroids carrying as little as 1 Joule of kinetic energy can produce measurable effects. We also find that the impact rate is highest when JWST faces in the direction of orbital motion about the Sun. By implementing a "meteoroid avoidance zone" that discourages observations within 75° of the ram direction, we estimate that JWST has reduced the impact rate by more than half.

Althea Moorhead↗