Cusp Dynamics and Ionospheric Outflow

  • S. A. Fuselier
  • S. B. Mende
  • T. E. Moore
  • H. U. Frey
  • S. M. Petrinec
  • E. S. Claflin
  • M. R. Collier


One of the IMAGE mission science goals is to understand the dayside auroral oval and its dynamic relationship to the magnetosphere. Two ways the auroral oval is dynamically coupled to the magnetosphere are through the injection of magnetosheath plasma into the magnetospheric cusps and through the ejection of ionospheric plasma into the magnetosphere. The ionospheric footpoints of the Earth’s magnetospheric cusps are relatively narrow regions in invariant latitude that map magnetically to the magnetopause. Monitoring the cusp reveals two important aspects of magnetic reconnection at the magnetopause. Continuous cusp observations reveal the relative contributions of quasi-steady versus impulsive reconnection to the overall transfer of mass, energy, and momentum across the magnetopause. The location of the cusp is used to determine where magnetic reconnection is occurring on the magnetopause. Of particular interest is the distinction between anti-parallel reconnection, where the magnetosheath and magnetospheric field lines are strictly anti-parallel, and component merging, where the magnetosheath and magnetospheric field lines have one component that is anti-parallel. IMAGE observations suggest that quasi-steady, anti-parallel reconnection is occurring in regions at the dayside magnetopause. However, it is difficult to rule out additional component reconnection using these observations.


Solar Wind Pitch Angle Magnetic Reconnection Neutral Line Magnetic Local Time 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Burch, J.L.: 1973, ‘Rate of erosion of dayside magnetic flux based on a quantitative study of polar cusp latitude on the interplanetary field’, Radio Sci. 8, 955.CrossRefADSGoogle Scholar
  2. Burch, J.L., Menietti, J.D. and Barfield, J.N.: 1986, ‘DE-1 Observations of solar wind-magnetospheric coupling processes in the polar cusp’, in Solar Wind-Magnetosphere Coupling, edited by Kamide, Y. and Slavin, J.A., p. 441, Terra Sci., Tokyo.CrossRefGoogle Scholar
  3. Candidi, M., Mastranntonio, G., Orsini, S. and Meng, C.-I: 1989, ‘Evidence for the influence of the interplanetary magnetic field azimuthal component on the polar cusp configuration’, J. Geophys. Res. 94, 13,585.CrossRefGoogle Scholar
  4. Carbary, J.F. and Meng, C.-L: 1988, Correlation of cusp width with AE(I2) and Bz, Planet. Space Sci. 36, 157.CrossRefADSGoogle Scholar
  5. Collin, H.L., Peterson, W.K., Lennartsson, O.W., Drake, J.F.: 1998, ‘The seasonal variation of auroral ion beams’, Geophys. Res. Lett. 25, 4071.CrossRefADSGoogle Scholar
  6. Crooker, N.U.: 1979, ‘Dayside merging and cusp geometry’, J. Geophys. Res. 84, 951.CrossRefADSGoogle Scholar
  7. Frank, L.A.: 1971, ‘Plasmas in the Earth’s polar magnetosphere’, J. Geophys. Res. 76, 5202.CrossRefADSGoogle Scholar
  8. Frey, H.U., Mende, S.B., Immel, T.J., Fuselier, S.A., Claflin, E.S., Gérard, J.-C. and Hubert, B.: 2002, ‘Proton aurora in the cusp’, J. Geophys. Res. 107(A7), 1091, DOI 10.1029/2001JA900161.CrossRefGoogle Scholar
  9. Fuselier, S.A., Anderson, B.J. and Onsager, T.G.: 1997, ‘Electron and ion signatures of field line topology at the low-shear magnetopause’, J. Geophys. Res. 102, 4847.CrossRefADSGoogle Scholar
  10. Fuselier, S.A., Ghielmetti, A.G., Moore, T.E., Collier, M.R., Quinn, J.M., Wilson, G.R., Wurz, P., Mende, S.B., Frey, H.U., Jamar, C., Gerard, J.-C. and Burch, J.L.: 2001, Ton outflow observed by IMAGE: Implications for source regions and heating mechanisms’, Geophys. Res. Lett. 28, 1163.CrossRefADSGoogle Scholar
  11. Fuselier, S.A., Frey, H.U., Trattner, K.J., Mende, S.B. and Burch, J.L.: 2002a, ‘Cusp auroral dependence on IMF Bz’, J. Geophys. Res. 107(A7), 1111, DOI 10.1029/2001JA900165.CrossRefGoogle Scholar
  12. Fuselier, S.A., Collin, H.L., Ghielmetti, A.G., Claflin, E.S., Moore, T.E., Collier, M.R., Frey, H. and Mende, S.B.: 2002b, ‘Localized ion outflow in response to a solar wind pressure pulse’, J. Geophys. Res. 107(A7), 1203, DOI 10.1029/2001JA000297.CrossRefGoogle Scholar
  13. Fuselier, S.A., Waite, Jr., J.H., Avanov, L.A., Smirnov, V.M., Vaisberg, O.L., Siscoe, G.L. and Russell,C.T.: 2002c, ‘Characteristics of magnetosheath plasma in the vicinity of the high altitude cusp’, Planet. Space Sci. 50, 559–566.CrossRefADSGoogle Scholar
  14. Gérard, J.-C., Hubert, B., Meurant, M., Shematovitch, V.I., Bisikalo, D.V., Frey, H., Mende, S., Gladstone, G.R. and Carlson, C.W.: 2001, ‘Observation of the proton aurora with IMAGE FUV imager and simultaneous ion flux in situ measurements’, J. Geophys. Res. 106, 28,939.CrossRefGoogle Scholar
  15. Gosling, J.T. and Robson: 1985, Ton reflection, gyration, and dissipation at supercritical shocks’, in Collisionless Shocks in the Heliosphere: Reviews of Current Ressearch, Geohpys. Monogr. Ser., vol 35, edited by B.T. Tsurutani, B.T. and Stone, R.G., p. 141, AGU Washington, D.C.CrossRefGoogle Scholar
  16. Gosling, J.T., Thomsen, M.F., Bame, S.J., Elphic, R.C. and Russell, C.T.: 1990, ‘Plasma flow reversals at the dayside magnetopause and the origin of asymmetric polar cap convection’, J. Geophys. Res. 95, 8073.CrossRefADSGoogle Scholar
  17. Heikkila, W.J. and Winningham, J.D.: 1971, ‘Penetration of magnetosheath plasma to low altitudes through the dayside magnetospheric cusps’, J. Geophys. Res. 76, 883.CrossRefADSGoogle Scholar
  18. Mende, S.B., et al., ‘Far ultraviolet imaging from the IMAGE spacecraft’, Space Sci. Rev. 91, 287.Google Scholar
  19. Mende, S.B., Frey, H.U., Lampton, M., Gerard, J.-C., Hubert, B., Fuselier, S., Spann, J., Gladstone, R. and Burch, J.L.: 2001, ‘Global observations of proton and electron auroras in a substorm’, Geophys. Res. Lett. 28, 1139.CrossRefADSGoogle Scholar
  20. Milan, S.E., Lester, M., Cowley, S.W.H. and Brittnacher, M.: 2000, ‘Dayside convection and auroral morphology during an interval of northward interplanetary magnetic field’, Ann. Geophysicae 18, 436.CrossRefADSGoogle Scholar
  21. Moore, T.E., Chappell, C.R., Lockwood, M. and Waite, Jr., J.H.: 1985, ‘Superthermal ion signatures of auroral acceleration processes’, J. Geophys. Res. 90, 1611.CrossRefADSGoogle Scholar
  22. Moore, T.E. et al.: 1999, ‘Ionospheric mass ejection in response to a CME’, Geophys. Res. Lett. 26, 2339.CrossRefADSGoogle Scholar
  23. Moore, T.E. et al.: 2000, ‘The low-energy neutral atom imager for IMAGE’, in The IMAGE Mission, ed. Burch, J.L., Kluwer Academic Publishers, Dordrecht, p. 155–195.CrossRefGoogle Scholar
  24. Moore, T.E. et al.: 2001, ‘Low energy neutral atoms in the magnetosphere’, Geophys. Res. Lett. 28, 1143.CrossRefADSGoogle Scholar
  25. Newell, P.T., and Meng, C.-I.: 1988, ‘The cusp and cleft/LLBL: Low latitude identification and statistical local time variation’, J. Geophys. Res. 93, 14,549.Google Scholar
  26. Newell, P.T. and Meng, C.-I.: 1992, ‘Mapping the dayside ionosphere to the magnetosphere according to particle precipitation characteristics’, Geophys. Res. Lett. 19, 609.CrossRefADSGoogle Scholar
  27. Newell, P.T. and Sibeck, D.G.: 1993, ‘By fluctuations in the magnetosheath and azimuthal flow velocity transients in the dayside ionosphere’, Geophys. Res. Lett. 20, 1719.CrossRefADSGoogle Scholar
  28. Newell, P.T., Meng, C.-I., Sibeck, D.G. and Lepping, R.: 1989, ‘Some low-altitude cusp dependencies on the interplanetary magnetic field’, J. Geophys. Res. 94, 8921.CrossRefADSGoogle Scholar
  29. Øieroset M., Yamauchi, M., Liszka, L. and Hultqvist, B.: 1999, ‘Energetic ion outflow from the dayside ionosphere: Categorization, classification and statistical study’, J. Geophys. Res. 104, 24,915.Google Scholar
  30. Onsager, T.G., Kletzing, C.A., Austin, J.B. and MacKiernan, H.: 1993, ‘Model of magnetosheath plasma in the magnetosphere: Cusp and mantle particles at low altitudes’, Geophys. Res. Lett. 20, 479.CrossRefADSGoogle Scholar
  31. Peterson, W.K., Collin, H.L., Doherty, M.F. and Bjorklund, C.M.: 1992, ‘0+ and He+ restricted and extended (b-modal) ion conic distributions’, Geophys. Res. Lett. 19, 1439.CrossRefADSGoogle Scholar
  32. Phan, T.D. et al.: 2000, ‘Extended magnetic reconnection at the Earth’s magnetopause from detection of by-directional jets’, Nature 404, 848.CrossRefADSGoogle Scholar
  33. Reiff, PH., Hill, T.W. and Burch, J.L.: 1977, ‘Solar wind plasma injection at the dayside magneto-spheric cusp’, J. Geophys. Res. 82, 479.CrossRefADSGoogle Scholar
  34. Rosenbauer, H., Gruenwaldt, H., Montgomery, M.D., Paschmann, G. and Sckopke, N.: 1975, ‘HEOS 2 plasma observations in the distant polar magnetosphere: the plasma mantle’, J. Geophys. Res. 80, 2723.CrossRefADSGoogle Scholar
  35. Russell, C.T., Chappell, C.R., Montgomery, M.D., Neugebauer, M. and Scarf, F.L.: 1971, ‘Ogo 5 observations of the polar cusp on November 1, 1968’, J. Geophys. Res. 76, 6743.CrossRefADSGoogle Scholar
  36. Shelley, E.G.: 1985, ‘Circulation of energetic ions of terrestrial origin in the magnetosphere’, Adv. Space Res. 5, 401.CrossRefADSGoogle Scholar
  37. Shelley, E.G., Johnson, R.G. and Sharp, R.D.: 1972, ‘Satellite observations of energetic heavy ions during a geomagnetic storm’, J. Geophys. Res. 11, 6104.CrossRefADSGoogle Scholar
  38. Smith, M.F. and Lockwood, M.: 1990, ‘The pulsating cusp’, Geophys. Res. Lett. 17, 1069.CrossRefADSGoogle Scholar
  39. Sonnerup, B.U.: l974,‘Ö, Magnetopause reconnection rate’, J. Geophys. Res. 79, 1546.CrossRefADSGoogle Scholar
  40. Sonnerup, B.U., Paschmann, Ö.G., Papamastorakis, I., Sckopke, N., Haerendel, G., Bame, S.J., As-bridge, J.R., Gosling, J.T. and Russell, C.T.: 1981, ‘Evidence for magnetic field reconnection at the Earth’s magnetopause’, J. Geophys. Res. 86, 10,049.Google Scholar
  41. Tsyganenko, N.A.: 1995, ‘Modeling the Earth’s magnetospheric magnetic field confined within a realistic magnetopause’, J. Geophys. Res. 100, 5599.CrossRefADSGoogle Scholar
  42. Wing, S., Newell, P.T. and Ruohoniemi, J.M.: 2001, ‘Double cusp: Model prediction and observational verification’, J. Geophys. Res. 106, 25,571.CrossRefGoogle Scholar
  43. Woch J. and Lundin, R.: 1992, ‘Magnetosheath plasma precipitation in the polar cusp and its control by the interplanetary magnetic field’, J. Geophys. Res. 97, 1421.CrossRefADSGoogle Scholar
  44. Yau, A.W., Beckwith, P.H., Peterson, W.K. and Shelley, E.G.: 1985, ‘Long-term (solar cycle) and seasonal variations of upflowing ionospheric ion events at DE 1 altitudes’, J. Geophys. Res. 90,6395.CrossRefADSGoogle Scholar
  45. Zhou, X.W., Russell, C.T., G.Le, Fuselier, S.A. and Scudder, J.D.: 2000, ‘Solar wind control of the polar cusp at high latitude’, J. Geophys. Res. 105, 245.CrossRefADSGoogle Scholar

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • S. A. Fuselier
    • 1
  • S. B. Mende
    • 2
  • T. E. Moore
    • 3
  • H. U. Frey
    • 2
  • S. M. Petrinec
    • 1
  • E. S. Claflin
    • 1
  • M. R. Collier
    • 3
  1. 1.Lockheed Martin Advanced Technology CenterUSA
  2. 2.University of CaliforniaBerkeleyUSA
  3. 3.Goddard Space Flight CenterUSA

Personalised recommendations