(U) Improved Space Environment Models

(The effects of any budget/program decisions made since the information was collected during 1997-98 are NOT reflected in the National Security Space Road Map (NSSRM).)

Overview: (U)
(U)  The 55 Space Weather Squadron (SWXS) requires a full suite of coupled, first-principle physics, integrated space environment models to meet warfighter requirements for timely, accurate space environment forecasts and their potential effects on warfighter systems.  This includes models of solar activity, interplanetary space, and the earth's magnetosphere, ionosphere, and neutral upper atmosphere. 

Description: (U)
(U) There are several different types of models which are required.  These include:

- (U) Solar Activity Models.  Models of solar activity are needed to forecast activity such as coronal mass ejections (CMEs), high-energy proton emissions, and significant x-ray, UV and radio emissions.  These events drive severe near-earth space environment conditions that can have serious impacts to military systems, both in space and on the ground.  These models could complement the Solar Electro-optical Observing Network (SEON), SXI, space- and ground-based coronagraphs to provide accurate forecasts of significant solar activity.  The 55 Space Weather Squadron (SWXS) currently has no capability to forecast these types of events.  

- (U) Interplanetary Space Models.  These models would be used to help forecast arrival times of CMEs, proton events, and other solar wind enhancements at the earth's magnetopause due to their propagation through interplanetary space.  These models could complement instruments such as SMEI, space-based coronagraphs, and a solar wind satellite to provide accurate forecasts of the onset of geomagnetic storms.  These storms, in turn, can increase drag on low earth orbit (LEO) satellites, cause satellite sensor upsets, and effect HF and satellite communications.

- (U) Magnetospheric Models.  These models would provide forecasts of magnetospheric conditions that can impact satellite sensors, guidance systems, and circuitry which can in turn lead to degradation/destruction of sensors, loss of attitude control and spurious commands.  These models would receive inputs from solar and interplanetary models and feed ionospheric and neutral atmospheric models.  These models could complement instruments such as the Compact Environmental Anomaly Sensor (CEASE) and the Space and Atmospheric Burst Reporting System (SABRS) to enhance magnetospheric forecast capabilities.

- (U) Ionospheric Models.  Ionospheric models would provide forecasts of ionospheric disturbances such as scintillation, sporadic E, spread F, and enhanced D-region density.  These disturbances cause a variety of warfighter system impacts.  Scintillation can cause degradation/complete loss of ultra-high frequency (UHF) satellite communications transmissions and induce phase errors in global positioning system (GPS) signals, which could degrade timing and positioning accuracy.  Sporadic E can be interpreted as false signals by tracking radars.  Enhanced D-region densities can seriously degrade or totally absorb HF communications.  Ionospheric disturbances can also effect various surveillance and reconnaissance systems.  These models can complement systems and sensors such as the Communications/Navigation Outage Forecasting System (C/NOFS), the Special Sensor Ultraviolet Spectrographic Imager (SSUSI), the Special Sensor Ultraviolet Limb Imager (SSULI), the Digital Ion Drift Meter (DIDM), a Geostationary UV Imager, the Digital Ionospheric Sounding System (DISS), and the Ionospheric Measuring System (IMS) to improve the forecast capabilities of the 55 SWXS.

- (U) Neutral Atmosphere Models.  These models are the final link in this coupled space environment model suite.  Solar activity induces, through the interplanetary/magnetospheric/ ionospheric system, variations in the neutral upper atmosphere that can cause increased satellite drag, which in turn can impact space surveillance radar capabilities to detect and track LEO systems.  This becomes especially important in detecting and tracking small space debris, which can have disastrous consequences to manned spaceflight, both the current Shuttle and the future Space Station.  Neutral models should also include algorithms to forecast atomic oxygen concentrations; atomic oxygen has extremely corrosive effects on spacecraft coatings, mirrors, and solar panels.  These models could complement neutral atmospheric measurement instruments such as accelerometers to improve neutral atmospheric forecasting capabilities.

User Impact: (U)
(U) To be supplied.

Programmatics: (U)
(U) Programmable.
	(U) IOC: 10/2008 (1QFY2009).

Related Initiatives: (U)
(U) C/NOFS, CEASE, Cloud Profiling System, SABRS, Space Weather Analysis, Wind LIDAR ATD

Related Requirements: (U)
(U) None.

Related Categories: (U)
(U) Forecasting

Road Map Placements: (U)
(U) ENVIRONMENTAL MONITORING.

Lead Office: (U)
(U) Air Force.

Date of Information: (U)
21 November 1997

(The effects of any budget/program decisions made since the information was collected during 1997-98 are NOT reflected in the National Security Space Road Map (NSSRM).)