GOLD AGU poster McClintock

Views:
 
Category: Education
     
 

Presentation Description

No description available.

Comments

Presentation Transcript

Global-scale Observations of the Limb and Disk (GOLD): Mission Implementation W. McClintock1, M. Lankton1, R. Eastes2, A. Aksnes2, D. Anderson3, L. Andersson1, A. Burns4, M. Codrescu3, R. Daniell5, F. Eparvier1, J. Harvey6, T. Immel7, A. Krywonos6, J. Lumpe5, G. Prölss8, A. Richmond4, D. Rusch1, S. Solomon4, D. Strickland5 and T. Woods1 1. Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309 United States; 2. Florida Space Institute, MS FAI, Kennedy Space Center, FL 32899 United States; 3. NOAA-SEC and CIRES-Univ. of Colorado, 325 Broadway, Boulder, CO 80303 United States; 4. NCAR, PO Box 3000, Boulder, CO 80307-3000 United States; 5. Computational Physics, Inc., 8001 Braddock Rd, Suite 210, Springfield, VA 22151 United States; 6. CREOL, University of Central Florida, Orlando, FL 32816 United States; 7. Space Science Lab., Univ. of California, Berkeley, CA 94720 United States; 8. Institut für Astrophysik und Extraterrestrische Forschung, Auf dem Hugel 71, Bonn, 53121 Germany: 

Global-scale Observations of the Limb and Disk (GOLD): Mission Implementation W. McClintock1, M. Lankton1, R. Eastes2, A. Aksnes2, D. Anderson3, L. Andersson1, A. Burns4, M. Codrescu3, R. Daniell5, F. Eparvier1, J. Harvey6, T. Immel7, A. Krywonos6, J. Lumpe5, G. Prölss8, A. Richmond4, D. Rusch1, S. Solomon4, D. Strickland5 and T. Woods1 1. Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80309 United States; 2. Florida Space Institute, MS FAI, Kennedy Space Center, FL 32899 United States; 3. NOAA-SEC and CIRES-Univ. of Colorado, 325 Broadway, Boulder, CO 80303 United States; 4. NCAR, PO Box 3000, Boulder, CO 80307-3000 United States; 5. Computational Physics, Inc., 8001 Braddock Rd, Suite 210, Springfield, VA 22151 United States; 6. CREOL, University of Central Florida, Orlando, FL 32816 United States; 7. Space Science Lab., Univ. of California, Berkeley, CA 94720 United States; 8. Institut für Astrophysik und Extraterrestrische Forschung, Auf dem Hugel 71, Bonn, 53121 Germany Abstract The Global-scale Observations of the Limb and Disk (GOLD) mission of opportunity will fly an ultraviolet imaging spectrograph on a geostationary satellite to measure densities and temperatures in the thermosphere and ionosphere. From this vantage point, GOLD will observe emissions from an entire hemisphere (disk) and the horizon (limb) of the Earth. On the limb stellar occultations will provide information that is not available from the emissions. Analysis of these data will answer four specific science questions: 1. What is the global-scale response of the thermosphere and ionosphere to geomagnetic forcing? 2. What is the global-scale response of the thermosphere and ionosphere to changing EUV radiation? 3. What are the solar & geospace causes of small-scale ionospheric density irregularities? 4. What are the global-scale tidal amplitude and phase variations? Answers to these questions will address the central question of the Living With a Star (LWS) program: What is the global-scale response of the thermosphere and ionosphere to forcing in the integrated Sun-Earth system? This presentation discusses the GOLD measurement approach and describes the GOLD mission implementation, including the instrument design concept, its accommodation to the spacecraft, observation scenarios, and the ground data system. GOLD Investigation Goals Answer the central question of the NASA Living with a Star Program: What is the global-scale response of the thermosphere and ionosphere to forcing in the integrated Sun-Earth system? GOLD Observations 1. First global-scale neutral temperature measurements (from N2 Lyman-Birge-Hopfield [LBH] band rotational temperatures at 150±30 km) 2. O/N2 column density ratios (from dayside oxygen 135.6 nm & LBH observations) 3. Electron density variations in latitude and longitude (oxygen 135.6 nm emissions from O+ + e) 4. O2 density profile at altitudes of 150-240 km (day and night) by stellar occultation 5. O emission profiles (day, from observations of 135.6 nm) on the limb 6. Electron density vertical profile (night, oxygen 135.6 nm emissions from O+ + e) on the limb GOLD Driving Performance Requirements Global-scale imaging of O and N2 column emission rates on the dayside with average latitude-longitude spatial scales < 200 km, with a signal-to-noise ratio (SNR) of 10 for the O/N2 ratio, and with a 30-minute cadence Limb profiles of O (180 – 400 km, dayside) and O (300 – 700 km nightside) emission rates with 25-km vertical resolution, 12.5-km sampling interval, and with SNR = 10 Stellar occultation measurements of O2 absorption on the dayside and nightside limbs from 140 km to 250 km with 10-km vertical resolution 4. Global-scale high-spectral-resolution images of dayside N2 LBH band emissions with 0.1-nm spectral resolution, 500 km spatial resolution, and 1-hour temporal cadence GOLD System Architecture Satisfies Performance Requirements Ground Segment Example Measurement and Derived Data Products Data products, including measured values (O and N2 radiances on the disk and limb and O2 absorption profiles on the limb) and derived parameters (O/N2, O2, T, and Ne), are generated at the Science Data Center located at UCF. Examples below are observations of nightside density irregularities observed by the Image satellite (left), and O/N2 ratio at 180 km and temperature a 170 km during the May 1997 geomagnetic storm (center and right - calculated from the CISM-CMIT model). Derived Data Products Simulated GOLD Data Simulated output for a standard image from the low resolution channel including photon noise. GOLD data images are 1024 x 1024 Spectral (abscissa) versus spatial (ordinate) images of the disk, which are packetized in the processor and routed to a spacecraft transmitter for immediate down-link. These are converted to count spectra and integrated radiance values at the SDC. Spacecraft GOLD will be mounted on the nadir facing deck of a Lockheed-Martin A2100 Spacecraft owned and operated by SES Americom. The baseline schedule places GOLD in an orbit located over North America. Data are down-linked to SES Americom ground stations in real-time and transmitted to LASP and UCF. Instrument GOLD implementation meets the driving performance requirements using a pair of independent telescope-spectrometers equipped with scan mirrors and controlled by a single microprocessor assembly. GOLD Science Data Center GOLD science questions have direct correspondence to LWS/Geospace objectives Equatorial Ionosphere 1. Electric fields 2. Ionospheric density (nighttime) Aurora 1. Location 2. Conductivity Thermosphere 1. Temperature 2. Density 3. Composition 4. Tides Science Closure GOLD science team members (D. Anderson, A. Burns, M. Codrescu , R. Daniell, R. Eastes, A. Richmond, S. Solomon, and D. Strickland) will use GOLD measurement and derived data products to test and improve existing models and to develop new models. Assimilative Mapping of Ionospheric Electrodynamics (AMIE) Atmospheric Ultraviolet Radiance Integrated Code (AURIC) Center for Integrated Space Weather Modeling (CISM) Coupled Magnetosphere Ionosphere Thermosphere (CMIT) Coupled Thermosphere Ionosphere Plasmasphere electrodynamics (CTIPe) Goddard Space Flight Center Lidar Observatory for Wind (GLOW) Global Assimulation Models of the Ionosphere (GAMIs) Global Theoretical Ionospheric Model (GTIM) Intra-system Cascade Excitation (ICE) NCAR Thermosphere-Ionosphere-Electrodynamics General-Circulation Model (TIE-GCM) SA41B-1413

authorStream Live Help