Overview of the imaging spectrometer instrument for NASA’s Surface Biology and Geology mission.
Following the 2017 release of the National Academies of Science, Engineering and Medicine’s Earth Science and Applications Decadal Survey (ESAS 2017), the National Aeronautics and Space Administration (NASA) announced the development of an Earth System Observatory (ESO), a series of missions designed to observe processes across the Earth’s interior, surface and atmosphere.
One of the key identified investigation in the ESO series is the Surface Biology and Geology (SBG) mission. SBG will measure the composition and properties of Earth’s land, inland waters, and coastal oceans. The architecture of this mission consists of 2 satellites one covering the Visible Shortwave Infrared (VSWIR) and the Thermal Infrared (TIR) spectrum respectively and is slated for launch in the later part of the decade.
This talk will focus on the new global coverage observation that will be made from space by the VSWIR Wide Swath (VSWIR-WS) imaging spectrometer instrument. This measurement is part of the Surface Biology and Geology (SBG) mission.
KEYWORDS: Satellites, Data modeling, Climatology, Calibration, Radiometry, Observatories, Space operations, Sensors, Microwave radiation, Temperature metrology
Launched 10 June 2011, the NASA’s Aquarius instrument onboard the Argentine built and managed Satélite de Aplicaciones Científicas (SAC-D) has been tirelessly observing the open oceans, confirming and adding new knowledge to the not so vast measured records of our Earth’s global oceans. This paper reviews the data collected over the last 3 years, it’s findings, challenges and future work that is at hand for the sleepless oceanographers, hydrologists and climate scientists. Although routine data is being collected, a snapshot is presented from almost 3-years of flawless operations showing new discoveries and possibilities of lot more in the future. Repetitive calibration and validation of measurements from Aquarius continue together with comparison of the data to the existing array of Argo temperature/salinity profiling floats, measurements from the recent Salinity Processes in the Upper Ocean Regional Study (SPURS) in-situ experiment and research, and to the data collected from the European Soil Moisture Ocean Salinity (SMOS) mission. This all aids in the optimization of computer model functions to improve the basic understanding of the water cycle over the oceans and its ties to climate. The Aquarius mission operations team also has been tweaking and optimizing algorithms, reprocessing data as needed, and producing salinity movies that has never been seen before. A brief overview of the accomplishments, technical findings to date will be covered in this paper.
KEYWORDS: Observatories, Space operations, Satellites, Calibration, Global Positioning System, Climatology, Sensors, Receivers, Control systems, Transmitters
The Aquarius/SAC-D observatory was launch in June 2011 from Vandenberg Air Force Base (VAFB), in California,
USA. This mission is the fourth joint earth-observation endeavor between NASA and CONAE. The primary objective
of the Aquarius/SAC-D mission is to investigate the links between global water cycle, ocean circulation and climate by
measuring Sea Surface Salinity (SSS). Over the last year, the observatory successfully completed system level
environmental and functional testing at INPE, Brazil and was transported to VAFB for launch operations. This paper
will present the challenges of this mission, the system, the preparation of the spacecraft, instruments, testing, launch, inorbit
checkout and commissioning of this Observatory in space.
The Aquarius/SAC-D mission is the fourth earth-observation satellite jointly developed by NASA and CONAE. This
international remote sensing mission (with contributions from USA, Argentina, Brazil, Italy, France and Canada) has the
primary objective to investigate the links between global water cycle, ocean circulation and climate by measuring Sea
Surface Salinity (SSS). The mission is undergoing Observatory level testing and being prepared to be launched from
USA. This paper will present the mission, instruments, testing and performance status of the Observatory and show the
final preparation towards launch.
The primary objective of the Aquarius/SAC-D earth-remote sensing mission will be to investigate the links between
global water cycle, ocean circulation and climate. Sea Surface Salinity (SSS) is a key parameter in understanding the
global water cycle and this mission will yield an unprecedented view of ocean's role in climate and weather. This
international partnership mission involving 6 countries is preparing for a launch in September 2010. The observatory
(spacecraft and Instruments), will accommodate the primary NASA provided instrument for measuring SSS and various
instruments from CONAE, ASI, CSA and CNES making additional atmospheric and environmental science
measurements. The observatory integration and testing occurs in Argentina and Brazil and launched to space from
United States. The project is currently in the final phases of Integration of the Observatory in Argentina and will
undergo environmental tests at the INPE-LIT test facility in Brazil before shipping to launch site in USA. An overview
of the mission along with the preparation status towards launch will be provided.
Sea Surface Salinity (SSS) is a key parameter in the global water cycle but it is not yet monitored from space.
Conventional in situ SSS sampling is too sparse to give the global view of salinity variability that a remote sensing
satellite can provide. The Aquarius/SAC-D Mission will make pioneering space-based measurements of global SSS
with the precision, resolution, and coverage needed to characterize salinity variations (spatial and temporal),
investigate the linkage between ocean circulation, the Earth's water cycle, and climate variability. It is being jointly
developed by NASA and the Space Agency of Argentina, the Comision Nacional de Actividades Espaciales
(CONAE). The Project is currently in implementation phase with the flight Aquarius Instrument undergoing
environmental testing at NASA-JPL/Caltech in California, USA and the SAC-D instruments and spacecraft
development undergoing at CONAE/INVAP facilities in Argentina. Aquarius/SAC-D launch is scheduled for May
2010.
KEYWORDS: Observatories, Temperature metrology, Space operations, Climatology, Environmental sensing, Radiometry, Sensors, Aerospace engineering, Data archive systems, Global Positioning System
Aquarius/SAC-D is a cooperative international mission developed between the National Aeronautics and Space Administration (NASA) of United States of America (USA) and the Comisión Nacional de Actividades Espaciales (CONAE) of Argentina.
The overall mission objective is to contribute to the understanding of the total Earth system and the consequences of the natural and man-made changes in the environment of the planet. Major themes are: ocean surface salinity, carbon, water cycle, geo-hazards, and cryosphere.
Christopher Martin, Thomas Barlow, William Barnhart, Luciana Bianchi, Brian Blakkolb, Dominique Bruno, Joseph Bushman, Yong-Ik Byun, Michael Chiville, Timothy Conrow, Brian Cooke, Jose Donas, James Fanson, Karl Forster, Peter Friedman, Robert Grange, David Griffiths, Timothy Heckman, James Lee, Patrick Jelinsky, Sug-Whan Kim, Siu-Chun Lee, Young-Wook Lee, Dankai Liu, Barry Madore, Roger Malina, Alan Mazer, Ryan McLean, Bruno Milliard, William Mitchell, Marco Morais, Patrick Morrissey, Susan Neff, Frederic Raison, David Randall, Michael Rich, David Schiminovich, Wes Schmitigal, Amit Sen, Oswald Siegmund, Todd Small, Joseph Stock, Frank Surber, Alexander Szalay, Arthur Vaughan, Timothy Weigand, Barry Welsh, Patrick Wu, Ted Wyder, C. Kevin Xu, Jennifer Zsoldas
The Galaxy Evolution Explorer (GALEX), a NASA Small Explorer Mission planned for launch in Fall 2002, will perform the first Space Ultraviolet sky survey. Five imaging surveys in each of two bands (1350-1750Å and 1750-2800Å) will range from an all-sky survey (limit mAB~20-21) to an ultra-deep survey of 4 square degrees (limit mAB~26). Three spectroscopic grism surveys (R=100-300) will be performed with various depths (mAB~20-25) and sky coverage (100 to 2 square degrees) over the 1350-2800Å band. The instrument includes a 50 cm modified Ritchey-Chrétien telescope, a dichroic beam splitter and astigmatism corrector, two large sealed tube microchannel plate detectors to simultaneously cover the two bands and the 1.2 degree field of view. A rotating wheel provides either imaging or grism spectroscopy with transmitting optics. We will use the measured UV properties of local galaxies, along with corollary observations, to calibrate the UV-global star formation rate relationship in galaxies. We will apply this calibration to distant galaxies discovered in the deep imaging and spectroscopic surveys to map the history of star formation in the universe over the red shift range zero to two. The GALEX mission will include an Associate Investigator program for additional observations and supporting data analysis. This will support a wide variety of investigations made possible by the first UV sky survey.
The advantages of photon-counting detectors such as the Ranicon over other detectors in space-based astronomy in the area of time-resolved imaging and spectroscopy are discussed. Details of a system to record the positions and absolute arrival times of individual photons are described, with emphasis on the time-tag module and detector electronics and data collection system. The use of a GPS system for accurate absolute timing when synchronizing observations from different observatories is suggested.
A data-collection system for use in astronomical observations with the resistive-anode detectors (Ranicons) described by Paresce et al. (1979 and 1988) is briefly characterized. Analog signals from the Ranicon pass through 12-bit A/D converters and (along with time information from a digital clock) into a 64-bit FIFO buffer, and the photon positions are calculated by a high-speed arithmetic-logic system capable of an event rate of 30 kHz (so that, by Poisson statistics, only about 21 percent of events will be missed). Results from successful timing tests of the system on the 2.2-m telescope at ESO are presented graphically.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.