5,356 research outputs found
Radial Velocity Prospects Current and Future: A White Paper Report prepared by the Study Analysis Group 8 for the Exoplanet Program Analysis Group (ExoPAG)
[Abridged] The Study Analysis Group 8 of the NASA Exoplanet Analysis Group
was convened to assess the current capabilities and the future potential of the
precise radial velocity (PRV) method to advance the NASA goal to "search for
planetary bodies and Earth-like planets in orbit around other stars.: (U.S.
National Space Policy, June 28, 2010). PRVs complement other exoplanet
detection methods, for example offering a direct path to obtaining the bulk
density and thus the structure and composition of transiting exoplanets. Our
analysis builds upon previous community input, including the ExoPlanet
Community Report chapter on radial velocities in 2008, the 2010 Decadal Survey
of Astronomy, the Penn State Precise Radial Velocities Workshop response to the
Decadal Survey in 2010, and the NSF Portfolio Review in 2012. The
radial-velocity detection of exoplanets is strongly endorsed by both the Astro
2010 Decadal Survey "New Worlds, New Horizons" and the NSF Portfolio Review,
and the community has recommended robust investment in PRVs. The demands on
telescope time for the above mission support, especially for systems of small
planets, will exceed the number of nights available using instruments now in
operation by a factor of at least several for TESS alone. Pushing down towards
true Earth twins will require more photons (i.e. larger telescopes), more
stable spectrographs than are currently available, better calibration, and
better correction for stellar jitter. We outline four hypothetical situations
for PRV work necessary to meet NASA mission exoplanet science objectives.Comment: ExoPAG SAG 8 final report, 112 pages, fixed author name onl
Infrared experiments for spaceborne planetary atmospheres research. Executive summary
The role of 0.5 to 300 micron remote sensing in planetary atmospheres exploration was evaluated by examining a broad range of measurement techniques including quantitative intercomparisons of existing and planned instruments by the phenomenological method. Key areas of infrared instrumentation requiring development for the investigations of atmospheres were identified
CASTER - a concept for a Black Hole Finder Probe based on the use of new scintillator technologies
The primary scientific mission of the Black Hole Finder Probe (BHFP), part of
the NASA Beyond Einstein program, is to survey the local Universe for black
holes over a wide range of mass and accretion rate. One approach to such a
survey is a hard X-ray coded-aperture imaging mission operating in the 10--600
keV energy band, a spectral range that is considered to be especially useful in
the detection of black hole sources. The development of new inorganic
scintillator materials provides improved performance (for example, with regards
to energy resolution and timing) that is well suited to the BHFP science
requirements. Detection planes formed with these materials coupled with a new
generation of readout devices represent a major advancement in the performance
capabilities of scintillator-based gamma cameras. Here, we discuss the Coded
Aperture Survey Telescope for Energetic Radiation (CASTER), a concept that
represents a BHFP based on the use of the latest scintillator technology.Comment: 12 pages; conference paper presented at the SPIE conference "UV,
X-Ray, and Gamma-Ray Space Instrumentation for Astronomy XIV." To be
published in SPIE Conference Proceedings, vol. 589
Calibration of the AKARI Far-Infrared Imaging Fourier Transform Spectrometer
The Far-Infrared Surveyor (FIS) onboard the AKARI satellite has a
spectroscopic capability provided by a Fourier transform spectrometer
(FIS-FTS). FIS-FTS is the first space-borne imaging FTS dedicated to
far-infrared astronomical observations. We describe the calibration process of
the FIS-FTS and discuss its accuracy and reliability. The calibration is based
on the observational data of bright astronomical sources as well as two
instrumental sources. We have compared the FIS-FTS spectra with the spectra
obtained from the Long Wavelength Spectrometer (LWS) of the Infrared Space
Observatory (ISO) having a similar spectral coverage. The present calibration
method accurately reproduces the spectra of several solar system objects having
a reliable spectral model. Under this condition the relative uncertainty of the
calibration of the continuum is estimated to be 15% for SW, 10% for
70-85 cm^(-1) of LW, and 20% for 60-70 cm^(-1) of LW; and the absolute
uncertainty is estimated to be +35/-55% for SW, +35/-55% for 70-85 cm^(-1) of
LW, and +40/-60% for 60-70 cm^(-1) of LW. These values are confirmed by
comparison with theoretical models and previous observations by the ISO/LWS.Comment: 22 pages, 10 figure
Importance of Calibration/Validation Traceability for Multi-Sensor Imaging Spectrometry Applications
Knowledge of calibration traceability is essential for ensuring the quality of data products relying on multiple sensors and especially true for imaging spectrometers. The current work discusses the expected impact that imaging spectrometers have in ensuring radiometric traceability for both multispectral and hyperspectral products. The Climate Absolute Radiance and Refractivity Observatory Pathfinder mission is used to show the role that high-accuracy imaging spectrometers can play in understanding test sites used for vicarious calibration of sensors. The associated Solar, Lunar for Absolute Reflectance Imaging Spectroradiometer calibration demonstration system is used to illustrate recent advances in laboratory radiometric calibration approaches that will allow both the use of imaging spectrometers as calibration standards as well as to ensure the consistency of the multiple imaging spectrometers expected to be on orbit in the next decade
Workshop on Advanced Technologies for Planetary Instruments, part 1
This meeting was conceived in response to new challenges facing NASA's robotic solar system exploration program. This volume contains papers presented at the Workshop on Advanced Technologies for Planetary Instruments on 28-30 Apr. 1993. This meeting was conceived in response to new challenges facing NASA's robotic solar system exploration program. Over the past several years, SDIO has sponsored a significant technology development program aimed, in part, at the production of instruments with these characteristics. This workshop provided an opportunity for specialists from the planetary science and DoD communities to establish contacts, to explore common technical ground in an open forum, and more specifically, to discuss the applicability of SDIO's technology base to planetary science instruments
Uncertainties for Pre- and Post-Launch Radiometric Calibration of Imaging Spectrometers for Multi-Sensor Applications
An important aspect to using imaging spectrometer data is the radiometric characterization and calibration of the sensors and validation of their data products and doing so with error budgets with known traceability. The radiometric accuracy of a given sensor is important for demonstrating the expected quality of data from the sensor. Known traceability allows data from multiple sensors to be directly comparable as will become more important in the near future with the expected launches of multiple imaging spectrometers from multiple countries, agencies, and commercial entities. The current work describes the state of pre- and post-launch radiometric absolute and relative uncertainties and their role in harmonising on-orbit data. Examples of prelaunch uncertainties based on the calibration of EnMAP and the calibration planned for the CLARREO Pathfinder Mission are presented highlighting recent work in the area of detector-based approaches using tunable laser sources. Post-launch calibration approaches for Pathfinder, EnMAP, CHIME, and DESIS including traditional vicarious calibration methods and the challenges of working with commercial data are presented. The vicarious calibration discussion relies on the example of the recently-available RadCalNet data to describe typical methods and challenges that will be faced when harmonising data between imaging spectrometers as well as with multispectral sensors
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