The National Space Science Data Center has created a Web page based on the latest magnetospheric magnetic field model of N. Tsyganenko. The page permits the computation of many parameters at a specified time and magnetospheric location. The model accounts for the magnetopause, ring current, magnetotail, regions 1 and 2 Birkeland currents, and effects of the interplanetary magnetic field (IMF) interconnection with the magnetospheric field. The model is dependent on the solar wind dynamic pressure, Dst, and IMF By and Bz components. References for further details on the model are Tsyganenko, JGR, v. 100, 5599-5612, 1995, and Tsyganenko and Stern, JGR, v. 101, 27187-27198, 1996. The model source codes, an extensive list of references, and news on the latest developments in that field can also be found at http://www-spof.gsfc.nasa.gov/Modeling/group.html.
The NSSDC Web page allows the specification of a point in time and space. The user may specify solar wind conditions and Dst values or may let the system look up actual values for past times from the hourly resolution OMNI data set. The page then computes several parameters for the specified conditions: the model field at the specified point and at its conjugate point; the dipole and corrected geomagnetic coordinates of the specified point and its conjugate point as well as the geographic coordinates of the latter; the location of maximum geocentric distance of and the B-minimum value along the model field line through the specified point.
This service is part of an array of similar services provided by NSSDC for several geophysical models, including ionospheric, atmospheric, and trapped particle models in addition to geomagnetic and magnetospheric field models. The URL for the Web page linking to all these models is http://nssdc.gsfc.nasa.gov/space/model/.
Erin D. Gardner, firstname.lastname@example.org, (301) 286-0163
Hughes STX, Code 633, NASA Goddard Space Flight Center
Greenbelt, MD 20771, U.S.A.