H. Singer, R. Viereck, T. Onsager, L. Matheson, and D. Speich

1
Geosynchronous Operational Environmental
Satellites (GOES) Space Environment Monitor
3 hours
Solar X-ray Sensor
H. Singer, R. Viereck, T. Onsager, L. Matheson,
and D. Speich NOAA Space Environment Center

• Utility of the GOES XRS
• XRS continues to provide the primary standard for
  solar flare magnitude
• Used by both NOAA/SEC and the Air Force 55th
  Weather Squadron
• Real-time XRS data provides the first indications
  of solar flare activity
• Forecast Alerts and Warnings are sent out based
  on the initial XRS observation of a flare.
• - Alerts and Warnings are sent when XRS sees
  flux of gtM5.0 and gtX1.0
• The XRS data is used to produce the
  Radio-Blackout NOAA Scale
• GOES x-ray data will be expanded greatly with the
  addition of the Solar X-ray Imager (SXI) on GOES
  M
• New XRS Products

Abstract Since their inception in the 1970's,
the GOES satellites have monitored the sources of
space weather on the sun and the effects of space
weather at Earth. The Space Environment Monitor
(SEM) package on GOES monitors solar X-rays,
solar energetic particles, magnetospheric
energetic particles, galactic cosmic rays, and
Earth's magnetic field. These measurements are
important for providing alerts and warnings to
many customers, including satellite operators,
the power utilities, and NASA's human activities
in space. Some of these data also form the basis
for our new NOAA Space Weather Scales. GOES SEM
data are among the most widely used spacecraft
data sets by the national and international
research community.
Satellite Environment as Defined by GOES
Solar Proton Prediction Product http//sec.noaa.g
ov/sgreer/gprot/index.html
Magnetometer
GOES
Utility of the GOES Magnetometer

• Detecting magnetopause crossings
• Alerting customers to solar wind shocks or sudden
  impulses
• Assessing the level of geomagnetic activity
• Distinguishing among different sources of
  energetic particle events
• Developing techniques for new operational
  applications
• Providing data to NGDC for archives and the
  scientific community
• Real-time data to the US Air Force 55th Space
  Weather Squadron
• Supporting rocket launch decisions and other
  real-time activities
• Conducting research for understanding the space
  environment

Solar Wind Shock Impact and Magnetopause
Crossings at Geosynchronous Orbit
During magnetopause crossings spacecraft
encounter magnetic fields that can be directed
opposite to what is normally expected. These
conditions can have undesirable effects on
spacecraft that use torquer currents as part of
their attitude control and momentum management.
The plasma surrounding the spacecraft has a
higher density when the spacecraft moves outside
the magnetosphere.
Space Environment Monitor

• Space Environment Monitor (SEM)
• Energetic Particle Sensor (EPS) Monitors the
  electrons, protons, and alpha particles fluxes
• Electrons 0.6 gt 4.0 MeV
• Protons 0.8 gt 700 MeV,
• Alpha Particles 4 gt 3400 MeV
• Magnetometer (MAG) Monitors the vector magnetic
  field
• Sample Rate 0.512 second
• Sensitivity 0.1 nT
• Range/- 1000 nT
• X-Ray Sensor (XRS) Monitors whole-Sun x-ray
  brightness in two bands
• Channel 1 0.5 - 4 Angstroms
• Channel 2 1 - 8 Angstroms

Future of GOES

• GOES NOPQ
• SEC Involvement in the Next Generation of GOES
  Spacecraft
• Define requirements and instrument
  specifications
• Support and participate in procurement process
• Provide technical advice to NOAA, NASA, HSC
• - design reviews and test reviews, etc
• Participate in technical interchange meetings
• - lead and host magnetometer review
• Participate in weekly SEM telecons
• Provide expertise and participate in working
  group
• - e.g. communications, contamination
• Develop data processing, display, validation,
  dissemination, and products
• - major changes from previous series

Satellite Status
Energetic Particle Sensors
Utility of the GOES EPS/ HEPAD
GOES Energetic Electron and Proton
Measurements Serve as basis for real-time
Alerts and Warnings of hazardous environmental
conditions Allow rapid assessment of
spacecraft anomalies Provide assessment of
conditions hazardous to humans in space
Provide long-term database of environmental
conditions Are distributed in real-time to
US Air Force Space Weather Services EPS/HEPAD
data are used to produce the Radiation Storm
NOAA Scale
GOES NOPQ Improvements
Region of Frequent Satellite Anomalies
Dawn

• Energetic Particle Sensor (EPS)
• Multi-directional Proton and Electron
  Measurements
• Extended Electron and Proton Energy Ranges
• Enhanced Services
• - Improved alerts and warnings
• - Improved assessment of spacecraft anomalies and
  degradation
• - Direct measurement of the Spacecraft Charging
  Environment
• - Better predictions of environmental conditions
• XRS/EUV
• Add five EUV channels
• Enhanced Services
• - Improved orbit prediction for low-earth-orbit
• - Improved ionospheric parameterization
• - Better predictions of iono/thermosphere
• SXI
• Improved sensitivity and spatial Resolution

SEC Involvement with GOES Program
Sun
Radiation Belt Electrons and Solar Protons
Geosync. Orbit

• SEM Measurements Provide Space Environment Data
  for Operations and Science.
• Approximately 30 SEC staff members contribute
  significant portions of their time to support the
  GOES project
• Positions include managers, scientists,
  forecasters, engineers, programmers and software
  engineers, technicians, system and network
  administrators
• Tasks include instrument definition and future
  mission planning, program and instrument
  management, ground station support, data ingest,
  data processing and archive, data validation and
  quality control, real-time operations, computer
  hardware and software support, algorithm
  development, image processing, database design
  and development, displays design and development,
  research, and data dissemination

Magnetopause
Ionospheric variations cause navigation errors in
GPS
Thermospheric Density variations cause orbit
instabilities or even re-entry
3 Hours
Baker et al., 1998