Studies of electron and ion temperatures at 500 km altitude during sunrise using Indian SROSS C2 satellite

• Published in: Advances in space research Vol. 43; no. 2; pp. 273 - 281
• Main Authors: Aggarwal, Malini, Joshi, H.P., Iyer, K.N., Jivani, M.N.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 15-01-2009; Elsevier
• Subjects: Astronomy; Earth, ocean, space; Electron temperature; Exact sciences and technology; External geophysics; Ion temperature; Morning overshoot; Solar activity; SROSS C2; SROSS C2; Morning overshoot; Solar activity; Electron temperature; Ion temperature; Minimum solar activity; Solar electrons; Winter; Summer; Sunrise; Space research
• ISSN: 0273-1177; 1879-1948
• DOI: 10.1016/j.asr.2008.04.006

Solar dependence of electron and ion temperatures (
T
e and
T
i) in the ionosphere is studied using RPA data onboard SROSS C2 at an altitude of ∼500
km and 77°E longitude during early morning hours (04:00–07:00
LT) for three solar activities: solar minimum, moderate and maximum during winter, summer and equinox months in 10°S–20°N geomagnetic latitude. In winter the morning overshoot phenomenon is observed around 06:00
LT (
T
e enhances to ∼4000
K) during low-solar activity and to
T
e
∼
3800
K, during higher solar activity. In summer, it is observed around 05:30
LT, but the rate of
T
e enhancement is higher during moderate solar activity (∼2700
K/hr) than the low-solar activity (∼1700
K/hr). During equinox, this phenomenon is delayed and is observed around 06:00
LT (∼4200
K) during all three activities.
In winter, the
T
i shows an enhancement (∼2300 from ∼700
K) around 06:00
LT during low-solar activity but during other activities, it raise smoothly with the progress of the morning. In summer,
T
i increases at a rate of 260
K/hr during low and moderate activities and with half the rate (∼130
K/hr) during high-solar activity. And in equinox months, the
T
i is lower during high-solar activity than in low-solar activity.