23 research outputs found
JWST Optical Telescope Element Center of Curvature Test
James Webb Space Telescope (JWST) is a large infrared observing space telescope which will launch in 2020. The observatory is comprised of 4 major subsystems; (1) Optical Telescope Element (OTE), (2) Integrated Science Instrument Module (ISIM), (3) Sunshield, (4) Spacecraft Bus. The OTE and ISIM are integrated together at Goddard Space Flight Center to form the OTIS assembly
JWST OTE Development Status
This slide presentation reviews the status of the optical telescope element (OTE) for the James Webb Space Telescope (JWST). Information about the cryotests that have been performed, and the test of the Primary Mirror Segment Assembly (PMSA) is included. Also views of the progress on the secondary, tertiary Mirror Segment Assembly and the fine steering motor are included. Information is included about the status of other structures. The critical design audit (CDA) of the OTE is scheduled for October of 2009
LISA Telescope Challenges
The LISA Mission proposal was selected by ESA's Science Program Committee (SPC) for the L3 Cosmic Visions launch opportunity, and is currently in a Phase A mission formulation study. An essential component of the instrument is a set of optical telescopes that make precision displacement measurements between pairs of proof masses that are flying drag-free in three separate satellites. We discuss the key requirements on the telescope, the current design, and discuss progress toward solving some of the key challenges for realizing the telescope designs
James Webb Space Telescope Optical Telescope Element/Integrated Science Instrument Module (OTIS) Status
The James Webb Space Telescope Optical Telescope Element (OTE) and Integrated Science Instrument Module (ISIM) are integrated together to form the OTIS. Once integrated, the OTIS undergoes primary mirror center of curvature optical tests, electrical and operational tests, acoustics and vibration testing at the Goddard Space Flight Center before being shipped to the Johnson Space Center for cryogenic optical testing of the OTIS. In preparation for the cryogenic optical testing, the JWST project has built a Pathfinder telescope and has completed two Optical Ground System Equipment (OGSE) cryogenic optical tests with the Pathfinder. In this paper, we will summarize optical test results to date and status the final Pathfinder test and the OTIS integration and environmental test preparation
James Webb Space Telescope Optical Telescope Element Integrated Science Instrument Module (OTIS) Status
The James Webb Space Telescope Optical Telescope Element (OTE) and Integrated ScienceInstrument Module (ISIM)are integrated together to form the OTIS. Once integrated, the OTIS undergoes primary mirrorcenter of curvatureoptical tests, electrical and operational tests, acoustics and vibration testing at the Goddard SpaceFlight Center beforebeing shipped to the Johnson Space Center for cryogenic optical testing of the OTIS. In preparationfor the cryogenicoptical testing, the JWST project has built a Pathfinder telescope and has completed two OpticalGround SystemEquipment (OGSE) cryogenic optical tests with the Pathfinder. In this paper, we will summarize opticaltest results todate and status the final Pathfinder test and the OTIS integration and environmental test preparation
James Webb Space Telescope Optical Telescope Element Mirror Coatings
James Webb Space Telescope (JWST) Optical Telescope Element (OTE) mirror coating program has been completed. The science goals of the JWST mission require a uniform, low stress, durable optical coating with high reflectivity over the JWST spectral region. The coating has to be environmentally stable, radiation resistant and compatible with the cryogenic operating environment. The large size, 1.52 m point to point, light weight, beryllium primary mirror (PM) segments and flawless coating process during the flight mirror coating program that consisted coating of 21 flight mirrors were among many technical challenges. This paper provides an overview of the JWST telescope mirror coating program. The paper summarizes the coating development program and performance of the flight mirrors
James Webb Space Telescope Optical Telescope Element (OTE) Mirror Coatings
No abstract availabl
An Atomic Gravitational Wave Interferometric Sensor in Low Earth Orbit (AGIS-LEO)
We propose an atom interferometer gravitational wave detector in low Earth
orbit (AGIS-LEO). Gravitational waves can be observed by comparing a pair of
atom interferometers separated over a ~30 km baseline. In the proposed
configuration, one or three of these interferometer pairs are simultaneously
operated through the use of two or three satellites in formation flight. The
three satellite configuration allows for the increased suppression of multiple
noise sources and for the detection of stochastic gravitational wave signals.
The mission will offer a strain sensitivity of < 10^(-18) / Hz^(1/2) in the 50
mHz - 10 Hz frequency range, providing access to a rich scientific region with
substantial discovery potential. This band is not currently addressed with the
LIGO or LISA instruments. We analyze systematic backgrounds that are relevant
to the mission and discuss how they can be mitigated at the required levels.
Some of these effects do not appear to have been considered previously in the
context of atom interferometry, and we therefore expect that our analysis will
be broadly relevant to atom interferometric precision measurements. Finally, we
present a brief conceptual overview of shorter-baseline (< 100 m) atom
interferometer configurations that could be deployed as proof-of-principle
instruments on the International Space Station (AGIS-ISS) or an independent
satellite.Comment: 37 pages, 21 figure
Picometer Level Spatial Metrology for Next Generation Telescopes
During the testing of the primary mirror segments for JWST, our team realized that some of the tools and techniques we had developed could be pushed further to achieve picometer resolution.We began developing incremental techniques for measuring, controlling, sensing to picometer levelsSeveral recent peer reviewed papers have shown that we can measure this level of change, control it with actuators, and potentially even develop active architectures using these ideasWe will show how the work on JWST evolved to systems applicable to measure picometer and even sub-picometer levels, show the results, and discuss implications for future telescope like LUVOIR and Habe
JWST Pathfinder Telescope Integration
The James Webb Space Telescope (JWST) is a 6.5m, segmented, IR telescope that will explore the first light of the universe after the big bang. In 2014, a major risk reduction effort related to the Alignment, Integration, and Test (AI&T) of the segmented telescope was completed. The Pathfinder telescope includes two Primary Mirror Segment Assemblies (PMSA's) and the Secondary Mirror Assembly (SMA) onto a flight-like composite telescope backplane. This pathfinder allowed the JWST team to assess the alignment process and to better understand the various error sources that need to be accommodated in the flight build. The successful completion of the Pathfinder Telescope provides a final integration roadmap for the flight operations that will start in August 2015