The impact of intense fluxes of energetic protons on the low-latitude ionosphere

Experiments on board low-Earth orbit satellites show that energetic particles (tens of keV) of the Earth’s radiation belt can penetrate to the equatorial ionosphere. Impact of the energetic particles on the upper atmosphere and ionosphere was studied for the case of the geomagnetic storm on 22 July 2009. We present changes of local ion concentration in the low-latitude ionosphere at night measured by the C/NOFS satellite at heights 400-800 km during the magnetic storm and quiet days. The ionospheric density during the storm was compared with a simultaneous observation of enhancements of 30-80 keV proton fluxes measured by the NOAA/POES satellites near the equator at height ~850 km. We suggest that ionospheric irregularities at night can be caused by effect of energetic protons.

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Storm-time ionization enhancements at the topside low-latitude ionosphere

Annales Geophysicae ◽

10.5194/angeo-26-867-2008 ◽

2008 ◽

Vol 26 (4) ◽

pp. 867-876 ◽

Cited By ~ 15

Author(s):

A. Dmitriev ◽

H.-C. Yeh

Keyword(s):

Radiation Belt ◽

Temporal Dynamics ◽

Geomagnetic Storms ◽

Energetic Particles ◽

Low Latitude ◽

Ion Density ◽

Low Latitude Ionosphere ◽

Using Data ◽

Mev Protons ◽

Earth Radiation

Abstract. Ion density enhancements at the topside low-latitude ionosphere during a Bastille storm on 15–16 July 2000 and Halloween storms on 29–31 October 2003 were studied using data from ROCSAT-1/IPEI experiment. Prominent ion density enhancements demonstrate similar temporal dynamics both in the sunlit and in the nightside hemispheres. The ion density increases dramatically (up to two orders of magnitude) during the main phase of the geomagnetic storms and reaches peak values at the storm maximum. The density enhancements are mostly localized in the region of a South Atlantic Anomaly (SAA), which is characterized by very intense fluxes of energetic particles. The dynamics of near-Earth radiation was studied using SAMPEX/LEICA data on >0.6 MeV electrons and >0.8 MeV protons at around 600 km altitude. During the magnetic storms the energetic particle fluxes in the SAA region and in its vicinity increase more than three orders of magnitude. The location of increased fluxes overlaps well with the regions of ion density enhancements. Two mechanisms were considered to be responsible for the generation of storm-time ion density enhancements: prompt penetration of the interplanetary electric field and abundant ionization of the ionosphere by enhanced precipitation of energetic particles from the radiation belt.

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The Effect of Atmospheric Drag Force on the Elements of Low Earth Orbital Satellites at Minimum Solar Activity

NeuroQuantology ◽

10.14704/nq.2021.19.9.nq21134 ◽

2021 ◽

Vol 19 (9) ◽

pp. 24-37

Author(s):

Najlaa Ozaar Hasan ◽

Wafaa Hasan Ali Zaki ◽

Ahmed Kader Izzet

Keyword(s):

Solar Activity ◽

Low Earth Orbit ◽

Atmospheric Drag ◽

Size Parameter ◽

Mass Ratio ◽

Orbital Elements ◽

Unperturbed Motion ◽

Minimum Solar Activity ◽

Low Earth Orbit Satellites ◽

The Impact

Researching and modeling perturbations is essential in astrodynamics because it gives information on the deviations from the satellite's normal, idealized, or unperturbed motion. Examined the impact of non-conservative atmospheric drag and orbital elements of low-earth-orbit satellites under low solar activity. The study is consisting of parts, the first looks at the effects of atmospheric drag on LEO satellites different area to mass ratios, and the second looks at different inclination values. Modeling the impacts of perturbation is included in each section, and the final portion determines the effects of atmospheric drag at various node values. The simulation was run using the Celestial Mechanics software system's SATORB module (Beutler, 2005), which solves the perturbation equations via numerical integration. The findings were examined using Matlab 2012. Conclusion that the impacts are stronger for retrograde orbits, which is due to the fact that the satellite moves in the opposite direction. The atmospheric drag effects for all orbital elements were increased by increasing the area to mass ratio. When the node value rises, the size parameter changes slightly, but the other orbital elements change. At varying inclinations, it is found that the changes in orbital elements due to atmospheric drug.

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A case study of the day-to-day occurrence of plasma irregularities in low-latitude ionosphere from multi-satellite observations

10.5194/angeo-2019-128 ◽

2019 ◽

Author(s):

Weihua Luo ◽

Chao Xiong ◽

Zhengping Zhu ◽

Shanshan Chang ◽

Xiao Yu

Keyword(s):

Low Earth Orbit ◽

Low Latitude ◽

Plasma Irregularities ◽

Republic Of China ◽

Plasma Bubbles ◽

Defense Meteorological Satellite Program ◽

Open Issue ◽

The Republic ◽

Low Latitude Ionosphere ◽

Gravity Recovery

Abstract. Day-to-day variability of the occurrence of plasma irregularities in low-latitude ionosphere is still an open issue. In this study, we report the occurrence of post-sunset plasma bubbles and blobs detected by the First satellite of the Republic of China (ROCSAT-1) in the same longitude sector (170° E) on two successive days, under geomagnetically quiet and disturbed conditions, respectively. Multi-Low Earth orbit (LEO) missions, like the Defense Meteorological Satellite Program (DMSP) F13 and F15, the Gravity Recovery and Climate Experiment (GRACE) and the Challenging Mini-satellite Payload (CHAMP) satellites are used to study the preferable conditions for the occurrence of plasma bubbles and blobs. The observations from the CHAMP and GRACE show that the Equatorial Ionization Anomaly (EIA) was enhanced significantly before the occurrence of plasma irregularities on both two successive days. We suggest that the enhancement of post-sunset eastward electric field is the most important factor for the day-to-day development of the plasma irregularity in equatorial and low-latitude ionosphere. In addition, the meridional neutral wind plays an important role in the occurrence of low-latitude plasma blobs.

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