Space Weather from the SEM-N Sensor Suite for Operational Use W.F. Denig 1, P. Purcell 1,2 & C.D. Reimer 3 1 NOAA National Geophysical Data Center 2 CSU Cooperative Institute for Research in the Atmosphere 3 SMC Defense Meteorological Satellite Program Systems Group 91 st Annual Meeting – AMS

2 AMS, Jan 2011 REFERENCE ONLY NOT PRESENTED ABSTRACT New Operational SWx Sensor SPACE WEATHER FROM THE SPACE ENVIRONMENT MONITOR-NEXT (SEM-N) SENSOR SUITE FOR OPERATIONAL USE W. F. Denig 1, P. Purcell 1,2 and C. D. Reimer 3 1 NOAA/National Geophysical Data Center (NGDC), 325 Broadway, Boulder, CO U.S.A. 2 Cooperative Institute for Research in the Atmosphere (CIRA), Colorado State University, Fort Collins, CO U.S.A. 3 SMC Defense Meteorological Satellite Program Systems Group, Los Angeles AFB, CA U.S.A. Monitoring the near-earth environment is essential for protection of space assets and their capabilities from extremes in space weather. Particle radiation impacts military communication, navigation, aviation and spacecraft operations, as these systems may be vulnerable to high energy particles. Using in situ high energy particle sensors allow modeling of the earth environmental response to solar activity and provide space weather predictions for satellite protection and management - from possible planning of satellite maneuvers to shutting down on-board systems and sensors to avoid damage. Additionally, knowledge of the particle environment constrains engineering design of satellites for survivability and allows sensor data to be corrected for contamination by particle fluxes. Synergism with UV and V is remote sensing of atmospheric disturbances (e.g. aurora) allows calibration checks of the electro-optical sensors and independent input to atmospheric models. The Defense Weather Satellite System (DWSS), the follow-on DoD program to the National Polar-orbiting Operational Environmental Satellite System (NPOESS), will fly the Space Environment Monitor – Next (SEM-N) for detection of such space particles. SEM-N is a suite of sensors based on heritage particle sensors flying on the Defense Meteorological Satellite Program (DMSP) and the Polar Operational Environmental Satellite (POES) system for the DoD and DOC/NOAA, respectively, and on NASA planetary research missions. The sensor suite will provide space particle data continuity for DMSP and POES. This paper will focus on the performance capabilities of SEM-N for space weather forecasting, for early warning to protect military assets in space and on the ground, and to provide effective operational planning.

3 AMS, Jan 2011 USAF Polar Weather Satellite Defense Weather Satellite System (DWSS) Follow-on Program to DMSP Defense Meteorological Satellite Program Sun-synchronous orbit at 840 km / 98.7 o  Single satellite 17:30 LTAN Complements 13:30 LTAN Complements 21:30 LTAN Space Environment EDRs  Auroral Boundary (AB)  Auroral Energy Deposition (AED)  Supra-thermal to Auroral Charged Part. (SACP)  Medium-energy Charged Particles (MECP)  Energetic Ions (EI) Space Environment Monitor – Next (SEM-N)  SSJ5-N – Electrostatic Analyzer  EPM – Energetic Particle Monitor  HES – High Energy Sensor LTAN – Local Time of Ascending Node EDR – Environmental Data Record JPSS – Joint Polar Satellite System (NOAA) Photo Credit: Lockheed Martin Auroral over Greenland - DMSP

4 AMS, Jan 2011 SEM-N Hardware Space Environment Monitor - Next Sensor Suite Characteristics: SSJ5-N – Electro-Static Analyzer Measures electrons & protons Energy range: 30 eV – 30 keV Total field of view: 90 o x 4 o Heritage: DMSP SSJ4/5 EPM – Particle Spectrometer Measures electrons & protons Electron range: 30 keV to <1 MeV Proton range: 30 keV to 10 MeV Some ion mass discrimination Time-of-flight capabilities Heritage: NASA Messenger HES – High Energy (Ion) Sensor Shielded solid-state detectors Proton range: 10 MeV to >140 MeV Heritage: POES MEPED SEM-N H/W under development by the JHU Applied Physics Laboratory. First DWSS launch is in ~2018. Special Sensor J5 (SSJ5-N) Energetic Particle Monitor (EPM) High Energy Sensor (HES)

5 AMS, Jan 2011 SEM-N Algorithms Space Environment Monitor - Next MECP Data Flow Diagram (Logical View) The NOAA National Geophysical Data Center (NGDC) is responsible for the development of the SEM-N ground-processing algorithms (science codes). Algorithm Theoretical Basis Documents (ATBDs) & code flow diagrams under development (post-PDR maturity). Program Office is considering the use of the Algorithm Development Language (ADL) for the operational code.

6 AMS, Jan 2011 SEM-N Traceability Chart Sensor to System Impacts Slide provided by Tom Sotirelis (JHU/APL)

7 AMS, Jan hour auroral composite from DMSP OLS Historical operational methods used white-light imagery data from the DMSP Operational Linescan System (see Meng [1976]). Auroral boundary identification Monitoring has now transitioned to a particle-based approach using the DMSP SSJ series of sensors (see Gussenhoven et al. [1987]). Alternative approaches include ultra-violet (UV) imaging of the auroral zone. ABNPAB Environmental Data Record Monitoring the Auroral Boundary DMSP polar pass using the SSJ AB = Auroral Boundary NP = ~North Pole Credit: Elvidge, NOAA/NGDC Credit: Denig, AFRL

8 AMS, Jan 2011 Environmental Data Record Auroral Energy Deposition Used to create a synthetic auroral oval map. Current methodology developed by Dave Evans (see Foster et al. [1986]). Alternative approaches under consideration. Calculates the total hemispheric power input from auroral electron precipitation (see Emery et al. [2008]). Credit: Unknown

9 AMS, Jan 2011 Environmental Data Record Supra-thermal to Auroral Energy Particles Energetic charged particle data used operationally to determine the equatorial aurora boundary and auroral energy deposition. Data from current operational sensors used in many scientific investigations including simple case studies and in multi-sensor investigations (White Paper submitted to the NRC Decadal Survey). DMSP SSJ5 Credit: Newell, JHU/APL Credit: Amptek

10 AMS, Jan 2011 Environmental Data Record Medium Energy Charged Particles Used to monitor the space radiation environment. Precipitating energetic protons and electrons within energy ranges up to several MeV are located at high latitudes and within the region of the South Atlantic Anomaly (SAA). Particle deposition can degrade radio communication can disrupt the proper operation of satellite systems and, when intensities are sufficiently high, increase the radiation dose to astronauts in space. Image Courtesy of ESA SEM MEPS Electron Data Channel

11 AMS, Jan 2011 Environmental Data Record Energetic Ions Measurement of very energetic protons, mostly of solar origin. Geo-effective energetic protons (>10 MeV) produce enhanced levels of ionization at altitudes below 100 km. Short wave radio waves at relatively high frequencies are absorbed by the increased ionospheric densities causing a complete blackout of radio communications (Polar Cap Absorption [PCA] event). Lower frequency waves that would normally reflect off the low altitude ( D- or E-region) ionospheric layers now do so at lower altitudes thereby changing dramatically their propagation paths. PCA events are particularly devastating to radio communications because they can last for days depending on the sizes and locations of the magnetic disturbances on the Sun that produce them. The commercial airline industry requires knowledge of possible PCA events for operational planning for polar routes.

12 AMS, Jan 2011 Current Launch Schedule 1 USAF/NOAA/Europe Polar Programs 1 After Mary Kicza – National Academies Committee on Earth Science, 07 July 2010

13 AMS, Jan 2011 Summary New Operational SWx Sensor (SEM-N) Space Environment Monitor – Next (SEM-N) is the follow- on operational space weather sensor for the DoD / NOAA Sensor under development for a 2018 launch – some capability improvements over current operational sensors Various SEM-N data products will be available for the SWx operational communities

14 AMS, Jan 2011 QUESTIONS?