Response of Venus exospheric temperature measured by neutral mass spectrometer to solar EUV flux measured by Langmuir probe on the Pioneer Venus orbiter

Journal Article · Thu Feb 01 04:00:00 EST 1990 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA095iA02p01091· OSTI ID:5029352

Mahajan, K K; Kasprzak, W T; Brace, L H; Niemann, H B; Hoegy, W R ^[1]

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1. NASA Goddard Space Flight Center, Greenbelt, MD (United States)

The photoelectron current from the Pioneer Venus Langmuir probe has provided measurements of the total flux of solar EUV photons at Venus since 1979. The neutral oxygen scale height measured by the orbiter neutral mass spectrometer has permitted the exospheric temperature to be derived furing the same mission. In this paper the EUV observations are used to examine the response of exospheric temperature to changes in solar activity, primarily those related to solar rotation. It is found that the dayside exospheric temperature quite faithfully tracks variations in the EUV flux. Comparison is also made with the Earth-based solar activity index F{sub 10.7} adjusted to the position of Venus. This index varied from 142 to 249 flux units (10{sup {minus}22} W m{sup {minus}2} Hz{sup {minus}1}) during the period of measurements. The exospheric temperature is better correlated with EUV flux than with the 10.7-cm solar radio flux.

• OSTI ID: 5029352
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 95:A2; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640107* -- Astrophysics & Cosmology-- Planetary Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ATMOSPHERES
CORRELATIONS
ELECTROMAGNETIC RADIATION
EXTREME ULTRAVIOLET RADIATION
MASS SPECTROMETERS
MEASURING INSTRUMENTS
PIONEER SPACE PROBES
PLANETARY ATMOSPHERES
PLANETS
RADIATIONS
SOLAR ACTIVITY
SOLAR FLUX
SOLAR RADIATION
SPACE VEHICLES
SPECTROMETERS
STELLAR RADIATION
TEMPERATURE MEASUREMENT
ULTRAVIOLET RADIATION
VEHICLES
VENUS PLANET