Pioneer 9 and Pioneer 10 observations of the solar wind associated with the August 1972 events

Journal Article · Tue Feb 01 04:00:00 EST 1977 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA082i004p00603· OSTI ID:7330068

Intriligator, D S

Observations are presented of the changes in the solar wind proton parameters at 0.8 and 2.2 AU as a result of the solar flares in August 1972. These observations were obtained by the NASA Ames Research Center solar wind plasma analyzer experiments on Pioneer 9 and Pioneer 10. High time resolution measurements are presented of the solar wind proton speed associated with the arrival of the interplanetary shocks at Pioneer 9 and Pioneer 10. For these events, differential ion energy per unit charge spectra are shown which indicate the changes in the solar wind ion distribution function associated with the arrival of each of the interplanetary shocks. Four fast shocks are identified at Pioneer 9, and it is found that previously the time of arrival of the first interplanetary shock at Pioneer 9 was not correctly identified. Two fast shocks and one reverse shock are identified at Pioneer 10. Calculations are performed to obtain the local shock speeds for each of these shocks observed at Pioneer 9 and Pioneer 10. On the basis of thse calculations the Pioneer 9/Pioneer 10 shock associations are reexamined, and it is found that contrary to previously published studies there was no significant deceleration of the interplanetray shocks between 0.8 and 2.2 AU.

• Research Organization: Physics Department, University of Southern California, Los Angeles, California 90007
• OSTI ID: 7330068
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 82:4; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640104* -- Astrophysics & Cosmology-- Solar Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BARYONS
ELEMENTARY PARTICLES
FERMIONS
HADRONS
INTERPLANETARY SPACE
NUCLEONS
PIONEER SPACE PROBES
PROTONS
SHOCK WAVES
SOLAR ACTIVITY
SOLAR FLARES
SOLAR WIND
SPACE
SPACE VEHICLES
VELOCITY