National Aeronautics and Space Administration

Living With A Star

Targeted Research and Technology

An Assessment of the Feasibility of Predicting Major Geomagnetic Disturbances from Monitors in the Inner Heliosphere (0.5 AU)

ROSES ID: NRA-00-OSS-01      Selection Year: 2001      

Program Element: Independent Investigation: LWS

Principal Investigator: Charles Farrugia

Affiliation(s): University of New Hampshire


A viable space weather tool must provide both timely and reliable predictions of major geomagnetic disturbances. Solar wind monitors positioned judiciously in orbit around the Sun at say ~0.5 AU are in principle capable of giving an advance warning of ~1.5-2.5 days of disruptive interplanetary configurations. However, it is crucial to ensure that the advantage of early warning be coupled with a knowledge of how these structures develop en route to 1 AU so as to be able to understand what properties these structures have when they reach Earth. Aside from a well-grounded knowledge of how the magnetosheath and the coupled magnetosphere-ionosphere system respond to various interplanetary triggers, an informed assessment presupposes improved further knowledge of the following: (a) correlation lengths (of both field and plasma) along the Sun-Earth line; (b) correlation lengths normal to the Sun-Earth line; (c) how interplanetary quantities known to correlate well with geomagnetic activity develop from 0.5 to 1 AU; (d) how (a) - (c) depend on the specific interplanetary configuration; and (e) on the system's history, i.e., whether the structures are transient or corotating; and (f) the number of monitors required to keep correlation values above a pre-assigned, able tolerance level.
For this proposed preliminary quantitative assessment there are extensive datasets which we shall use. The Helios 1 and 2 probes collected magnetic field and plasma data and data on particles of cosmic ray energies in the inner heliosphere (0.3 to 1.0 AU) during a major fraction of a solar cycle, with usable data for the purposes of this proposal from end of 1974 to mid-1981. Helios data will be supplemented by data from the IMP and ISEE 3 spacecraft which were, at least for a good fraction of the time, returning data from near Earth. Measurement of magnetospheric disturbances will be obtained from archived data.


Performance YearReferenceInvestigation TypeActions
1Jordanova, V. K.; Kistler, L. M.; Farrugia, C. J.; ...
not set


Performance YearReferenceActions
1Lepping, R. P.; Farrugia, C. J.; Jordanova, V. K.; ...

Export to PDF