GUVI

Global UltraViolet Imager

GUVI Biblio





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Found 5142 entries in the Bibliography.


Showing entries from 1 through 50


2022

Low-latitude plasma blobs above Africa: Exploiting GOLD and multi-satellite in situ measurements

Low-latitude plasma blobs are localized density enhancements of electron density that are occasionally observed in the night-time tropical ionosphere. Two-dimensional (2D) imaging of this phenomenon has been rare and frequently restricted to Central/South America, which is densely covered with ground-based airglow imagers and Global Navigation Satellite System (GNSS) receivers. In Africa, on the contrary, no 2D image of a blob has been reported. Here we present two low-latitude blob events above Africa, one in the Northern s ...

Park, Jaeheung; Min, Kyoung; Eastes, Richard; Chao, Chi; Kim, Hee-Eun; Lee, Junchan; Sohn, Jongdae; Ryu, Kwangsun; Seo, Hoonkyu; Yoo, Ji-Hyeon; Lee, Seunguk; Woo, Changho; Kim, Eo-Jin;

Published by: Advances in Space Research      Published on: may

YEAR: 2022     DOI: 10.1016/j.asr.2022.05.021

COSMIC-2; GOLD; ICON; Low-latitude blobs; NextSat-1; swarm

Low-latitude plasma blobs above Africa: Exploiting GOLD and multi-satellite in situ measurements

Low-latitude plasma blobs are localized density enhancements of electron density that are occasionally observed in the night-time tropical ionosphere. Two-dimensional (2D) imaging of this phenomenon has been rare and frequently restricted to Central/South America, which is densely covered with ground-based airglow imagers and Global Navigation Satellite System (GNSS) receivers. In Africa, on the contrary, no 2D image of a blob has been reported. Here we present two low-latitude blob events above Africa, one in the Northern s ...

Park, Jaeheung; Min, Kyoung; Eastes, Richard; Chao, Chi; Kim, Hee-Eun; Lee, Junchan; Sohn, Jongdae; Ryu, Kwangsun; Seo, Hoonkyu; Yoo, Ji-Hyeon; Lee, Seunguk; Woo, Changho; Kim, Eo-Jin;

Published by: Advances in Space Research      Published on: may

YEAR: 2022     DOI: 10.1016/j.asr.2022.05.021

COSMIC-2; GOLD; ICON; Low-latitude blobs; NextSat-1; swarm

Low-latitude plasma blobs above Africa: Exploiting GOLD and multi-satellite in situ measurements

Low-latitude plasma blobs are localized density enhancements of electron density that are occasionally observed in the night-time tropical ionosphere. Two-dimensional (2D) imaging of this phenomenon has been rare and frequently restricted to Central/South America, which is densely covered with ground-based airglow imagers and Global Navigation Satellite System (GNSS) receivers. In Africa, on the contrary, no 2D image of a blob has been reported. Here we present two low-latitude blob events above Africa, one in the Northern s ...

Park, Jaeheung; Min, Kyoung; Eastes, Richard; Chao, Chi; Kim, Hee-Eun; Lee, Junchan; Sohn, Jongdae; Ryu, Kwangsun; Seo, Hoonkyu; Yoo, Ji-Hyeon; Lee, Seunguk; Woo, Changho; Kim, Eo-Jin;

Published by: Advances in Space Research      Published on: may

YEAR: 2022     DOI: 10.1016/j.asr.2022.05.021

COSMIC-2; GOLD; ICON; Low-latitude blobs; NextSat-1; swarm

Low-latitude plasma blobs above Africa: Exploiting GOLD and multi-satellite in situ measurements

Low-latitude plasma blobs are localized density enhancements of electron density that are occasionally observed in the night-time tropical ionosphere. Two-dimensional (2D) imaging of this phenomenon has been rare and frequently restricted to Central/South America, which is densely covered with ground-based airglow imagers and Global Navigation Satellite System (GNSS) receivers. In Africa, on the contrary, no 2D image of a blob has been reported. Here we present two low-latitude blob events above Africa, one in the Northern s ...

Park, Jaeheung; Min, Kyoung; Eastes, Richard; Chao, Chi; Kim, Hee-Eun; Lee, Junchan; Sohn, Jongdae; Ryu, Kwangsun; Seo, Hoonkyu; Yoo, Ji-Hyeon; Lee, Seunguk; Woo, Changho; Kim, Eo-Jin;

Published by: Advances in Space Research      Published on: may

YEAR: 2022     DOI: 10.1016/j.asr.2022.05.021

COSMIC-2; GOLD; ICON; Low-latitude blobs; NextSat-1; swarm

New method for Earth neutral atmospheric density retrieval based on energy spectrum fitting during occultation with LE/Insight-HXMT

We propose a new method for retrieving the atmospheric number density profile in the lower thermosphere, based on the X-ray Earth occultation of the Crab Nebula with the Hard X-ray Modulation Telescope (Insight-HXMT) Satellite. The absorption and scattering of X-rays by the atmosphere result in changes in the X-ray energy, and the Earth’s neutral atmospheric number density can be directly retrieved by fitting the observed spectrum and spectrum model at different altitude ranges during the occultation process. The pointing ...

Yu, Daochun; Li, Haitao; Li, Baoquan; Ge, Mingyu; Tuo, Youli; Li, Xiaobo; Xue, Wangchen; Liu, Yaning;

Published by: Advances in Space Research      Published on: may

YEAR: 2022     DOI: 10.1016/j.asr.2022.02.030

Atmospheric density vertical profile; Energy spectrum fitting; X-ray occultation

New method for Earth neutral atmospheric density retrieval based on energy spectrum fitting during occultation with LE/Insight-HXMT

We propose a new method for retrieving the atmospheric number density profile in the lower thermosphere, based on the X-ray Earth occultation of the Crab Nebula with the Hard X-ray Modulation Telescope (Insight-HXMT) Satellite. The absorption and scattering of X-rays by the atmosphere result in changes in the X-ray energy, and the Earth’s neutral atmospheric number density can be directly retrieved by fitting the observed spectrum and spectrum model at different altitude ranges during the occultation process. The pointing ...

Yu, Daochun; Li, Haitao; Li, Baoquan; Ge, Mingyu; Tuo, Youli; Li, Xiaobo; Xue, Wangchen; Liu, Yaning;

Published by: Advances in Space Research      Published on: may

YEAR: 2022     DOI: 10.1016/j.asr.2022.02.030

Atmospheric density vertical profile; Energy spectrum fitting; X-ray occultation

The investigation on daytime conjugate hemispheric asymmetry along 100°E longitude using observations and model simulations: New insights

The hemispherical asymmetry of the low latitude region along 100°E ± 5°E is scrutinized for the year 2015 at magnetically conjugate points on seasonal and intra-seasonal time scales. Two conjugate Ionosonde station pairs are selected- one pair in the inner valley (from SEALION) and the other in the outer edges of the EIA region. The anomaly in the stations is estimated using the difference of low latitude NmF2 from the dip equatorial NmF2 in the same meridian. A monthly average scheme is used instead of a seasonal mean, ...

Kalita, B.; Bhuyan, P.; Nath, S.; Choudhury, M.; Chakrabarty, D.; Wang, K.; Hozumi, K.; Supnithi, P.; Komolmis, T.; . Y. Yatini, C; Le Huy, M.;

Published by: Advances in Space Research      Published on: may

YEAR: 2022     DOI: 10.1016/j.asr.2022.02.058

NmF2; asymmetry; Conjugate; EIA; model; Hemisphere; hmF2; Subsolar

Measurement of the vertical atmospheric density profile from the X-ray Earth occultation of the Crab Nebula with Insight-HXMT

\textlessp\textgreater\textlessstrong class="journal-contentHeaderColor"\textgreaterAbstract.\textless/strong\textgreater X-ray Earth occultation sounding (XEOS) is an emerging method for measuring the neutral density in the lower thermosphere. In this paper, the X-ray Earth occultation (XEO) of the Crab Nebula is investigated using the Hard X-ray Modulation Telescope (Insight-HXMT). The pointing observation data on the 30 September 2018 recorded by the low-energy X-ray telescope (LE) of Insight-HXMT are selected and analyse ...

Yu, Daochun; Li, Haitao; Li, Baoquan; Ge, Mingyu; Tuo, Youli; Li, Xiaobo; Xue, Wangchen; Liu, Yaning; Wang, Aoying; Zhu, Yajun; Luo, Bingxian;

Published by: Atmospheric Measurement Techniques      Published on: may

YEAR: 2022     DOI: 10.5194/amt-15-3141-2022

Measurement of the vertical atmospheric density profile from the X-ray Earth occultation of the Crab Nebula with Insight-HXMT

\textlessp\textgreater\textlessstrong class="journal-contentHeaderColor"\textgreaterAbstract.\textless/strong\textgreater X-ray Earth occultation sounding (XEOS) is an emerging method for measuring the neutral density in the lower thermosphere. In this paper, the X-ray Earth occultation (XEO) of the Crab Nebula is investigated using the Hard X-ray Modulation Telescope (Insight-HXMT). The pointing observation data on the 30 September 2018 recorded by the low-energy X-ray telescope (LE) of Insight-HXMT are selected and analyse ...

Yu, Daochun; Li, Haitao; Li, Baoquan; Ge, Mingyu; Tuo, Youli; Li, Xiaobo; Xue, Wangchen; Liu, Yaning; Wang, Aoying; Zhu, Yajun; Luo, Bingxian;

Published by: Atmospheric Measurement Techniques      Published on: may

YEAR: 2022     DOI: 10.5194/amt-15-3141-2022

Comments on “A new method to subtract dayglow for auroral observation of SSUSI in LBH ranges based on the improved AURIC” by Wang et al. (2021)

A paper A new method to subtract dayglow for auroral observation of SSUSI in LBH ranges based on the improved AURIC reports a new method to estimate the dayglow intensities in DMSP/SSUSI LBH bands using an improved AURIC model. It is claimed that the new method offers a better alternative than the SSUSI operational algorithm which uses a data based table. The paper showed a few examples and compared them with SSSUI operational results. The comparison indicated that the new method didn t offer any improvement and provided net ...

Zhang, Yongliang; Paxton, Larry; Schaefer, Robert;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: mar

YEAR: 2022     DOI: 10.1016/j.jastp.2022.105833

AURORA; dayglow; far ultraviolet emission

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Total Electron Content Variations during an HSS/CIR driven storm at high and middle latitudes

Geethakumari, Gopika; Aikio, Anita; Cai, Lei; Vanhamaki, Heikki; Pedersen, Marcus; Coster, Anthea; Marchaudon, Aurélie; Blelly, Pierre-Louis; Haberle, Veronika; Maute, Astrid; Ellahouny, Nada; Virtanen, Ilkka; Norberg, Johannes; Soyama, Shin-Ichiro; Grandin, Maxime;

Published by:       Published on: mar

YEAR: 2022     DOI: 10.5194/egusphere-egu22-8194

Far-ultraviolet airglow remote sensing measurements on Feng Yun 3-D meteorological satellite

\textlessp\textgreater\textlessstrong class="journal-contentHeaderColor"\textgreaterAbstract.\textless/strong\textgreater The Ionospheric Photometer (IPM) is carried on the Feng Yun 3-D (FY3D) meteorological satellite, which allows for the measurement of far-ultraviolet (FUV) airglow radiation in the thermosphere. IPM is a compact and high-sensitivity nadir-viewing FUV remote sensing instrument. It monitors 135.6 nm emission in the nightside thermosphere and 135.6 nm and N\textlessspan class="inline-formula"\textgreater$_\te ...

Wang, Yungang; Fu, Liping; Jiang, Fang; Hu, Xiuqing; Liu, Chengbao; Zhang, Xiaoxin; Li, JiaWei; Ren, Zhipeng; He, Fei; Sun, Lingfeng; Sun, Ling; Yang, Zhongdong; Zhang, Peng; Wang, Jingsong; Mao, Tian;

Published by: Atmospheric Measurement Techniques      Published on: mar

YEAR: 2022     DOI: 10.5194/amt-15-1577-2022

Far-ultraviolet airglow remote sensing measurements on Feng Yun 3-D meteorological satellite

\textlessp\textgreater\textlessstrong class="journal-contentHeaderColor"\textgreaterAbstract.\textless/strong\textgreater The Ionospheric Photometer (IPM) is carried on the Feng Yun 3-D (FY3D) meteorological satellite, which allows for the measurement of far-ultraviolet (FUV) airglow radiation in the thermosphere. IPM is a compact and high-sensitivity nadir-viewing FUV remote sensing instrument. It monitors 135.6 nm emission in the nightside thermosphere and 135.6 nm and N\textlessspan class="inline-formula"\textgreater$_\te ...

Wang, Yungang; Fu, Liping; Jiang, Fang; Hu, Xiuqing; Liu, Chengbao; Zhang, Xiaoxin; Li, JiaWei; Ren, Zhipeng; He, Fei; Sun, Lingfeng; Sun, Ling; Yang, Zhongdong; Zhang, Peng; Wang, Jingsong; Mao, Tian;

Published by: Atmospheric Measurement Techniques      Published on: mar

YEAR: 2022     DOI: 10.5194/amt-15-1577-2022

Solar and interplanetary events that drove two CIR-related geomagnetic storms of 1 June 2013 and 7 October 2015, and their ionospheric responses at the American and African equatorial ionization Anomaly regions

This study investigates the sequence of solar and interplanetary events that drove the 1 June 2013 and October 2015 geomagnetic storms and how the American (68°–78oE) and African (32°–42oE) Equatorial Ionization Anomaly (EIA) regions responded to them. We constructed the EIA structures by using Total Electron Content (TEC) and ionospheric irregularities derived from Global Navigation Satellite System (GNSS) receivers along with the study locations. We also analyzed disturbed time ionospheric electric field and model da ...

Oyedokun, Oluwole; Amaechi, P.; Akala, A.; Simi, K.; Ogwala, Aghogho; Oyeyemi, E.;

Published by: Advances in Space Research      Published on: mar

YEAR: 2022     DOI: 10.1016/j.asr.2021.12.027

geomagnetic storm; total electron content; Corotating Interacting Region; ionospheric irregularities

Solar and interplanetary events that drove two CIR-related geomagnetic storms of 1 June 2013 and 7 October 2015, and their ionospheric responses at the American and African equatorial ionization Anomaly regions

This study investigates the sequence of solar and interplanetary events that drove the 1 June 2013 and October 2015 geomagnetic storms and how the American (68°–78oE) and African (32°–42oE) Equatorial Ionization Anomaly (EIA) regions responded to them. We constructed the EIA structures by using Total Electron Content (TEC) and ionospheric irregularities derived from Global Navigation Satellite System (GNSS) receivers along with the study locations. We also analyzed disturbed time ionospheric electric field and model da ...

Oyedokun, Oluwole; Amaechi, P.; Akala, A.; Simi, K.; Ogwala, Aghogho; Oyeyemi, E.;

Published by: Advances in Space Research      Published on: mar

YEAR: 2022     DOI: 10.1016/j.asr.2021.12.027

geomagnetic storm; total electron content; Corotating Interacting Region; ionospheric irregularities

Solar and interplanetary events that drove two CIR-related geomagnetic storms of 1 June 2013 and 7 October 2015, and their ionospheric responses at the American and African equatorial ionization Anomaly regions

This study investigates the sequence of solar and interplanetary events that drove the 1 June 2013 and October 2015 geomagnetic storms and how the American (68°–78oE) and African (32°–42oE) Equatorial Ionization Anomaly (EIA) regions responded to them. We constructed the EIA structures by using Total Electron Content (TEC) and ionospheric irregularities derived from Global Navigation Satellite System (GNSS) receivers along with the study locations. We also analyzed disturbed time ionospheric electric field and model da ...

Oyedokun, Oluwole; Amaechi, P.; Akala, A.; Simi, K.; Ogwala, Aghogho; Oyeyemi, E.;

Published by: Advances in Space Research      Published on: mar

YEAR: 2022     DOI: 10.1016/j.asr.2021.12.027

geomagnetic storm; total electron content; Corotating Interacting Region; ionospheric irregularities

Plasma-neutral gas interactions in various space environments: Assessment beyond simplified approximations as a Voyage 2050 theme

In the White Paper, submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we present the importance of advancing our knowledge of plasma-neutral gas interactions, and of deepening our understanding of the partially ionized environments that are ubiquitous in the upper atmospheres of planets and moons, and elsewhere in space. In future space missions, the above task requires addressing the following fundamental questions: (A) How and by how much do plasma-neutral gas interactions influence the re-distribu ...

Yamauchi, Masatoshi; De Keyser, Johan; Parks, George; Oyama, Shin-ichiro; Wurz, Peter; Abe, Takumi; Beth, Arnaud; Daglis, Ioannis; Dandouras, Iannis; Dunlop, Malcolm; Henri, Pierre; Ivchenko, Nickolay; Kallio, Esa; Kucharek, Harald; Liu, Yong; Mann, Ingrid; Marghitu, Octav; Nicolaou, Georgios; Rong, Zhaojin; Sakanoi, Takeshi; Saur, Joachim; Shimoyama, Manabu; Taguchi, Satoshi; Tian, Feng; Tsuda, Takuo; Tsurutani, Bruce; Turner, Drew; Ulich, Thomas; Yau, Andrew; Yoshikawa, Ichiro;

Published by: Experimental Astronomy      Published on: mar

YEAR: 2022     DOI: 10.1007/s10686-022-09846-9

Collision cross-section; Future missions; Low-energy; Neutral gas; Plasma; Voyage 2050

Plasma-neutral gas interactions in various space environments: Assessment beyond simplified approximations as a Voyage 2050 theme

In the White Paper, submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we present the importance of advancing our knowledge of plasma-neutral gas interactions, and of deepening our understanding of the partially ionized environments that are ubiquitous in the upper atmospheres of planets and moons, and elsewhere in space. In future space missions, the above task requires addressing the following fundamental questions: (A) How and by how much do plasma-neutral gas interactions influence the re-distribu ...

Yamauchi, Masatoshi; De Keyser, Johan; Parks, George; Oyama, Shin-ichiro; Wurz, Peter; Abe, Takumi; Beth, Arnaud; Daglis, Ioannis; Dandouras, Iannis; Dunlop, Malcolm; Henri, Pierre; Ivchenko, Nickolay; Kallio, Esa; Kucharek, Harald; Liu, Yong; Mann, Ingrid; Marghitu, Octav; Nicolaou, Georgios; Rong, Zhaojin; Sakanoi, Takeshi; Saur, Joachim; Shimoyama, Manabu; Taguchi, Satoshi; Tian, Feng; Tsuda, Takuo; Tsurutani, Bruce; Turner, Drew; Ulich, Thomas; Yau, Andrew; Yoshikawa, Ichiro;

Published by: Experimental Astronomy      Published on: mar

YEAR: 2022     DOI: 10.1007/s10686-022-09846-9

Collision cross-section; Future missions; Low-energy; Neutral gas; Plasma; Voyage 2050

Plasma-neutral gas interactions in various space environments: Assessment beyond simplified approximations as a Voyage 2050 theme

In the White Paper, submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we present the importance of advancing our knowledge of plasma-neutral gas interactions, and of deepening our understanding of the partially ionized environments that are ubiquitous in the upper atmospheres of planets and moons, and elsewhere in space. In future space missions, the above task requires addressing the following fundamental questions: (A) How and by how much do plasma-neutral gas interactions influence the re-distribu ...

Yamauchi, Masatoshi; De Keyser, Johan; Parks, George; Oyama, Shin-ichiro; Wurz, Peter; Abe, Takumi; Beth, Arnaud; Daglis, Ioannis; Dandouras, Iannis; Dunlop, Malcolm; Henri, Pierre; Ivchenko, Nickolay; Kallio, Esa; Kucharek, Harald; Liu, Yong; Mann, Ingrid; Marghitu, Octav; Nicolaou, Georgios; Rong, Zhaojin; Sakanoi, Takeshi; Saur, Joachim; Shimoyama, Manabu; Taguchi, Satoshi; Tian, Feng; Tsuda, Takuo; Tsurutani, Bruce; Turner, Drew; Ulich, Thomas; Yau, Andrew; Yoshikawa, Ichiro;

Published by: Experimental Astronomy      Published on: mar

YEAR: 2022     DOI: 10.1007/s10686-022-09846-9

Collision cross-section; Future missions; Low-energy; Neutral gas; Plasma; Voyage 2050

Plasma-neutral gas interactions in various space environments: Assessment beyond simplified approximations as a Voyage 2050 theme

In the White Paper, submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we present the importance of advancing our knowledge of plasma-neutral gas interactions, and of deepening our understanding of the partially ionized environments that are ubiquitous in the upper atmospheres of planets and moons, and elsewhere in space. In future space missions, the above task requires addressing the following fundamental questions: (A) How and by how much do plasma-neutral gas interactions influence the re-distribu ...

Yamauchi, Masatoshi; De Keyser, Johan; Parks, George; Oyama, Shin-ichiro; Wurz, Peter; Abe, Takumi; Beth, Arnaud; Daglis, Ioannis; Dandouras, Iannis; Dunlop, Malcolm; Henri, Pierre; Ivchenko, Nickolay; Kallio, Esa; Kucharek, Harald; Liu, Yong; Mann, Ingrid; Marghitu, Octav; Nicolaou, Georgios; Rong, Zhaojin; Sakanoi, Takeshi; Saur, Joachim; Shimoyama, Manabu; Taguchi, Satoshi; Tian, Feng; Tsuda, Takuo; Tsurutani, Bruce; Turner, Drew; Ulich, Thomas; Yau, Andrew; Yoshikawa, Ichiro;

Published by: Experimental Astronomy      Published on: mar

YEAR: 2022     DOI: 10.1007/s10686-022-09846-9

Collision cross-section; Future missions; Low-energy; Neutral gas; Plasma; Voyage 2050

Plasma-neutral gas interactions in various space environments: Assessment beyond simplified approximations as a Voyage 2050 theme

In the White Paper, submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we present the importance of advancing our knowledge of plasma-neutral gas interactions, and of deepening our understanding of the partially ionized environments that are ubiquitous in the upper atmospheres of planets and moons, and elsewhere in space. In future space missions, the above task requires addressing the following fundamental questions: (A) How and by how much do plasma-neutral gas interactions influence the re-distribu ...

Yamauchi, Masatoshi; De Keyser, Johan; Parks, George; Oyama, Shin-ichiro; Wurz, Peter; Abe, Takumi; Beth, Arnaud; Daglis, Ioannis; Dandouras, Iannis; Dunlop, Malcolm; Henri, Pierre; Ivchenko, Nickolay; Kallio, Esa; Kucharek, Harald; Liu, Yong; Mann, Ingrid; Marghitu, Octav; Nicolaou, Georgios; Rong, Zhaojin; Sakanoi, Takeshi; Saur, Joachim; Shimoyama, Manabu; Taguchi, Satoshi; Tian, Feng; Tsuda, Takuo; Tsurutani, Bruce; Turner, Drew; Ulich, Thomas; Yau, Andrew; Yoshikawa, Ichiro;

Published by: Experimental Astronomy      Published on: mar

YEAR: 2022     DOI: 10.1007/s10686-022-09846-9

Collision cross-section; Future missions; Low-energy; Neutral gas; Plasma; Voyage 2050

Plasma-neutral gas interactions in various space environments: Assessment beyond simplified approximations as a Voyage 2050 theme

In the White Paper, submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we present the importance of advancing our knowledge of plasma-neutral gas interactions, and of deepening our understanding of the partially ionized environments that are ubiquitous in the upper atmospheres of planets and moons, and elsewhere in space. In future space missions, the above task requires addressing the following fundamental questions: (A) How and by how much do plasma-neutral gas interactions influence the re-distribu ...

Yamauchi, Masatoshi; De Keyser, Johan; Parks, George; Oyama, Shin-ichiro; Wurz, Peter; Abe, Takumi; Beth, Arnaud; Daglis, Ioannis; Dandouras, Iannis; Dunlop, Malcolm; Henri, Pierre; Ivchenko, Nickolay; Kallio, Esa; Kucharek, Harald; Liu, Yong; Mann, Ingrid; Marghitu, Octav; Nicolaou, Georgios; Rong, Zhaojin; Sakanoi, Takeshi; Saur, Joachim; Shimoyama, Manabu; Taguchi, Satoshi; Tian, Feng; Tsuda, Takuo; Tsurutani, Bruce; Turner, Drew; Ulich, Thomas; Yau, Andrew; Yoshikawa, Ichiro;

Published by: Experimental Astronomy      Published on: mar

YEAR: 2022     DOI: 10.1007/s10686-022-09846-9

Collision cross-section; Future missions; Low-energy; Neutral gas; Plasma; Voyage 2050

Plasma-neutral gas interactions in various space environments: Assessment beyond simplified approximations as a Voyage 2050 theme

In the White Paper, submitted in response to the European Space Agency (ESA) Voyage 2050 Call, we present the importance of advancing our knowledge of plasma-neutral gas interactions, and of deepening our understanding of the partially ionized environments that are ubiquitous in the upper atmospheres of planets and moons, and elsewhere in space. In future space missions, the above task requires addressing the following fundamental questions: (A) How and by how much do plasma-neutral gas interactions influence the re-distribu ...

Yamauchi, Masatoshi; De Keyser, Johan; Parks, George; Oyama, Shin-ichiro; Wurz, Peter; Abe, Takumi; Beth, Arnaud; Daglis, Ioannis; Dandouras, Iannis; Dunlop, Malcolm; Henri, Pierre; Ivchenko, Nickolay; Kallio, Esa; Kucharek, Harald; Liu, Yong; Mann, Ingrid; Marghitu, Octav; Nicolaou, Georgios; Rong, Zhaojin; Sakanoi, Takeshi; Saur, Joachim; Shimoyama, Manabu; Taguchi, Satoshi; Tian, Feng; Tsuda, Takuo; Tsurutani, Bruce; Turner, Drew; Ulich, Thomas; Yau, Andrew; Yoshikawa, Ichiro;

Published by: Experimental Astronomy      Published on: mar

YEAR: 2022     DOI: 10.1007/s10686-022-09846-9

Collision cross-section; Future missions; Low-energy; Neutral gas; Plasma; Voyage 2050

Thermospheric density enhancement and limb O 130.4 nm radiance increase during geomagnetic storms

We explore a connection between thermospheric density enhancement and increase in thermospheric O 130.4 nm radiance. We observe TIMED/GUVI enhancements in the limb 130.4 nm radiances at ∼400 and ∼520 km on the dayside during four intense geomagnetic storms in 2003 and 2004. The enhancements were well correlated with Dst and CHAMP total neutral density at 400 km which represents O density as O is the dominant species at those altitudes. At the 400 and 520 km altitudes, O 130.4 nm emissions are mostly created by two ...

Zhang, Yongliang; Paxton, Larry; Schaefer, R.;

Published by: Journal of Atmospheric and Solar-Terrestrial Physics      Published on: mar

YEAR: 2022     DOI: 10.1016/j.jastp.2022.105830

FUV emission; Geomagentic storms; neutral density; thermosphere

Contribution of the lower atmosphere to the day-to-day variation of thermospheric density

In this paper we carried out a numerical experiment using the Specified Dynamics mode of the Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension (SD-WACCM-X). One SD-WACCM-X run was with realistic Kp and F10.7 and the other with constant Kp and F10.7. By comparing the day-to-day variability of thermosphere mass density at 300 km (low earth orbit, LEO) and 120 km (reentry level) in these two runs, we find that the density variation at 300 km is mainly driven by geomagnetic and solar forcing ...

Yue, Jia; Yu, Wandi; Pedatella, Nick; Bruinsma, Sean; Wang, Ningchao; Liu, Huixin;

Published by: Advances in Space Research      Published on: jun

YEAR: 2022     DOI: 10.1016/j.asr.2022.06.011

thermosphere; Lower atmosphere; Modeling; Satelllite drag

Contribution of the lower atmosphere to the day-to-day variation of thermospheric density

In this paper we carried out a numerical experiment using the Specified Dynamics mode of the Whole Atmosphere Community Climate Model with thermosphere and ionosphere eXtension (SD-WACCM-X). One SD-WACCM-X run was with realistic Kp and F10.7 and the other with constant Kp and F10.7. By comparing the day-to-day variability of thermosphere mass density at 300 km (low earth orbit, LEO) and 120 km (reentry level) in these two runs, we find that the density variation at 300 km is mainly driven by geomagnetic and solar forcing ...

Yue, Jia; Yu, Wandi; Pedatella, Nick; Bruinsma, Sean; Wang, Ningchao; Liu, Huixin;

Published by: Advances in Space Research      Published on: jun

YEAR: 2022     DOI: 10.1016/j.asr.2022.06.011

thermosphere; Lower atmosphere; Modeling; Satelllite drag

Climatology of global, hemispheric and regional electron content variations during the solar cycles 23 and 24

We present the results of study on the variations of ionospheric total electron content (TEC) by using global, hemispheric, and regional electron contents computed from the global ionospheric maps (GIMs) for the period from 1999 to 2020. For a low and moderate solar activity, the global and regional electron contents vary linearly with solar 10.7 cm radio flux and EUV flux. While a saturation effect in the electron content verses EUV and F10.7 is found during the high solar activity periods at all regions, the maximum effec ...

Younas, Waqar; Amory-Mazaudier, C.; Khan, Majid; Amaechi, Paul;

Published by: Advances in Space Research      Published on: jul

YEAR: 2022     DOI: 10.1016/j.asr.2022.07.029

annual variation; global electron content; Ionosphere; semi-annual variation; total electron content

Climatology of global, hemispheric and regional electron content variations during the solar cycles 23 and 24

We present the results of study on the variations of ionospheric total electron content (TEC) by using global, hemispheric, and regional electron contents computed from the global ionospheric maps (GIMs) for the period from 1999 to 2020. For a low and moderate solar activity, the global and regional electron contents vary linearly with solar 10.7 cm radio flux and EUV flux. While a saturation effect in the electron content verses EUV and F10.7 is found during the high solar activity periods at all regions, the maximum effec ...

Younas, Waqar; Amory-Mazaudier, C.; Khan, Majid; Amaechi, Paul;

Published by: Advances in Space Research      Published on: jul

YEAR: 2022     DOI: 10.1016/j.asr.2022.07.029

annual variation; global electron content; Ionosphere; semi-annual variation; total electron content

A long-range forecasting model for the thermosphere based on the intelligent optimized particle filtering

The uncertainties associated with the variations in the thermosphere are responsible for the inaccurate prediction of the orbit decay of low Earth orbiting space objects due to the drag force. Accurate forecasting of the thermosphere is urgently required to avoid satellite collisions, which is a potential threat to the rapid growth of spacecraft applications. However, owing to the imperfections in the physics-based forecast model, the long-range forecast of the thermosphere is still primitive even if the accurate prediction ...

Ren, Dexin; Lei, Jiuhou;

Published by: Science China Earth Sciences      Published on: jan

YEAR: 2022     DOI: 10.1007/s11430-021-9847-9

Forecast; Intelligent optimized particle filter; thermosphere; Uncertain parameters

A long-range forecasting model for the thermosphere based on the intelligent optimized particle filtering

The uncertainties associated with the variations in the thermosphere are responsible for the inaccurate prediction of the orbit decay of low Earth orbiting space objects due to the drag force. Accurate forecasting of the thermosphere is urgently required to avoid satellite collisions, which is a potential threat to the rapid growth of spacecraft applications. However, owing to the imperfections in the physics-based forecast model, the long-range forecast of the thermosphere is still primitive even if the accurate prediction ...

Ren, Dexin; Lei, Jiuhou;

Published by: Science China Earth Sciences      Published on: jan

YEAR: 2022     DOI: 10.1007/s11430-021-9847-9

Forecast; Intelligent optimized particle filter; thermosphere; Uncertain parameters

Middle and low latitudes hemispheric asymmetries in ∑O/N2 and TEC during intense magnetic storms of solar cycle 24

We have investigated the global hemispheric differences in thermospheric ∑O/N2 and its impact on the ionospheric total electron content (TEC) at mid- and low-latitudes. Four intense storms of solar cycle 24 (SC-24) have been considered, three of them occurred in Spring equinox and one in Summer solstice season. It is found that the mid-latitudes region has exhibited a large decrease in ∑O/N2 during all the phases of the storms under consideration, which corresponds well to the observed negative storm effects. This decrea ...

Younas, Waqar; Khan, Majid; Amory-Mazaudier, C.; Amaechi, Paul; Fleury, R.;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.027

CTIPe model; Disturbed ∑O/N; GUVI/TIMED data; Hemispheric asymmetries; REC

Middle and low latitudes hemispheric asymmetries in ∑O/N2 and TEC during intense magnetic storms of solar cycle 24

We have investigated the global hemispheric differences in thermospheric ∑O/N2 and its impact on the ionospheric total electron content (TEC) at mid- and low-latitudes. Four intense storms of solar cycle 24 (SC-24) have been considered, three of them occurred in Spring equinox and one in Summer solstice season. It is found that the mid-latitudes region has exhibited a large decrease in ∑O/N2 during all the phases of the storms under consideration, which corresponds well to the observed negative storm effects. This decrea ...

Younas, Waqar; Khan, Majid; Amory-Mazaudier, C.; Amaechi, Paul; Fleury, R.;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.027

CTIPe model; Disturbed ∑O/N; GUVI/TIMED data; Hemispheric asymmetries; REC

Middle and low latitudes hemispheric asymmetries in ∑O/N2 and TEC during intense magnetic storms of solar cycle 24

We have investigated the global hemispheric differences in thermospheric ∑O/N2 and its impact on the ionospheric total electron content (TEC) at mid- and low-latitudes. Four intense storms of solar cycle 24 (SC-24) have been considered, three of them occurred in Spring equinox and one in Summer solstice season. It is found that the mid-latitudes region has exhibited a large decrease in ∑O/N2 during all the phases of the storms under consideration, which corresponds well to the observed negative storm effects. This decrea ...

Younas, Waqar; Khan, Majid; Amory-Mazaudier, C.; Amaechi, Paul; Fleury, R.;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.027

CTIPe model; Disturbed ∑O/N; GUVI/TIMED data; Hemispheric asymmetries; REC

Morphologies of ionospheric-equivalent slab-thickness and scale height over equatorial latitude in Africa

Accurate representation of ionospheric equivalent slab thickness (τ) and scale height (Hm) plays a crucial role in characterizing the complex dynamics of topside and bottomside ionospheric constituents. In the present work, we examined the corresponding morphologies of ionospheric profile parameters with collocated global positioning system (GPS) and Digisonde Portable Sounder (DPS) setups at an equatorial location in west Africa Ilorin (8.50°N, 4.68°E), during a low solar activity year 2010. The extracted τ from GPS and ...

Odeyemi, Olumide; Adeniyi, Jacob; Oyeyemi, Elijah; Panda, Sampad; Jamjareegulgarn, Punyawi; Olugbon, Busola; Oluwadare, Esholomo; Akala, Andrew; Olawepo, Adeniji; Adewale, Adekola;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.030

Global positioning system; Digital portable sounder; Equatorial latitude; Equivalent slab thickness; scale height

Morphologies of ionospheric-equivalent slab-thickness and scale height over equatorial latitude in Africa

Accurate representation of ionospheric equivalent slab thickness (τ) and scale height (Hm) plays a crucial role in characterizing the complex dynamics of topside and bottomside ionospheric constituents. In the present work, we examined the corresponding morphologies of ionospheric profile parameters with collocated global positioning system (GPS) and Digisonde Portable Sounder (DPS) setups at an equatorial location in west Africa Ilorin (8.50°N, 4.68°E), during a low solar activity year 2010. The extracted τ from GPS and ...

Odeyemi, Olumide; Adeniyi, Jacob; Oyeyemi, Elijah; Panda, Sampad; Jamjareegulgarn, Punyawi; Olugbon, Busola; Oluwadare, Esholomo; Akala, Andrew; Olawepo, Adeniji; Adewale, Adekola;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.030

Global positioning system; Digital portable sounder; Equatorial latitude; Equivalent slab thickness; scale height

Morphologies of ionospheric-equivalent slab-thickness and scale height over equatorial latitude in Africa

Accurate representation of ionospheric equivalent slab thickness (τ) and scale height (Hm) plays a crucial role in characterizing the complex dynamics of topside and bottomside ionospheric constituents. In the present work, we examined the corresponding morphologies of ionospheric profile parameters with collocated global positioning system (GPS) and Digisonde Portable Sounder (DPS) setups at an equatorial location in west Africa Ilorin (8.50°N, 4.68°E), during a low solar activity year 2010. The extracted τ from GPS and ...

Odeyemi, Olumide; Adeniyi, Jacob; Oyeyemi, Elijah; Panda, Sampad; Jamjareegulgarn, Punyawi; Olugbon, Busola; Oluwadare, Esholomo; Akala, Andrew; Olawepo, Adeniji; Adewale, Adekola;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.030

Global positioning system; Digital portable sounder; Equatorial latitude; Equivalent slab thickness; scale height

Morphologies of ionospheric-equivalent slab-thickness and scale height over equatorial latitude in Africa

Accurate representation of ionospheric equivalent slab thickness (τ) and scale height (Hm) plays a crucial role in characterizing the complex dynamics of topside and bottomside ionospheric constituents. In the present work, we examined the corresponding morphologies of ionospheric profile parameters with collocated global positioning system (GPS) and Digisonde Portable Sounder (DPS) setups at an equatorial location in west Africa Ilorin (8.50°N, 4.68°E), during a low solar activity year 2010. The extracted τ from GPS and ...

Odeyemi, Olumide; Adeniyi, Jacob; Oyeyemi, Elijah; Panda, Sampad; Jamjareegulgarn, Punyawi; Olugbon, Busola; Oluwadare, Esholomo; Akala, Andrew; Olawepo, Adeniji; Adewale, Adekola;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.030

Global positioning system; Digital portable sounder; Equatorial latitude; Equivalent slab thickness; scale height

Morphologies of ionospheric-equivalent slab-thickness and scale height over equatorial latitude in Africa

Accurate representation of ionospheric equivalent slab thickness (τ) and scale height (Hm) plays a crucial role in characterizing the complex dynamics of topside and bottomside ionospheric constituents. In the present work, we examined the corresponding morphologies of ionospheric profile parameters with collocated global positioning system (GPS) and Digisonde Portable Sounder (DPS) setups at an equatorial location in west Africa Ilorin (8.50°N, 4.68°E), during a low solar activity year 2010. The extracted τ from GPS and ...

Odeyemi, Olumide; Adeniyi, Jacob; Oyeyemi, Elijah; Panda, Sampad; Jamjareegulgarn, Punyawi; Olugbon, Busola; Oluwadare, Esholomo; Akala, Andrew; Olawepo, Adeniji; Adewale, Adekola;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.030

Global positioning system; Digital portable sounder; Equatorial latitude; Equivalent slab thickness; scale height

Morphologies of ionospheric-equivalent slab-thickness and scale height over equatorial latitude in Africa

Accurate representation of ionospheric equivalent slab thickness (τ) and scale height (Hm) plays a crucial role in characterizing the complex dynamics of topside and bottomside ionospheric constituents. In the present work, we examined the corresponding morphologies of ionospheric profile parameters with collocated global positioning system (GPS) and Digisonde Portable Sounder (DPS) setups at an equatorial location in west Africa Ilorin (8.50°N, 4.68°E), during a low solar activity year 2010. The extracted τ from GPS and ...

Odeyemi, Olumide; Adeniyi, Jacob; Oyeyemi, Elijah; Panda, Sampad; Jamjareegulgarn, Punyawi; Olugbon, Busola; Oluwadare, Esholomo; Akala, Andrew; Olawepo, Adeniji; Adewale, Adekola;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.030

Global positioning system; Digital portable sounder; Equatorial latitude; Equivalent slab thickness; scale height

Morphologies of ionospheric-equivalent slab-thickness and scale height over equatorial latitude in Africa

Accurate representation of ionospheric equivalent slab thickness (τ) and scale height (Hm) plays a crucial role in characterizing the complex dynamics of topside and bottomside ionospheric constituents. In the present work, we examined the corresponding morphologies of ionospheric profile parameters with collocated global positioning system (GPS) and Digisonde Portable Sounder (DPS) setups at an equatorial location in west Africa Ilorin (8.50°N, 4.68°E), during a low solar activity year 2010. The extracted τ from GPS and ...

Odeyemi, Olumide; Adeniyi, Jacob; Oyeyemi, Elijah; Panda, Sampad; Jamjareegulgarn, Punyawi; Olugbon, Busola; Oluwadare, Esholomo; Akala, Andrew; Olawepo, Adeniji; Adewale, Adekola;

Published by: Advances in Space Research      Published on: jan

YEAR: 2022     DOI: 10.1016/j.asr.2021.10.030

Global positioning system; Digital portable sounder; Equatorial latitude; Equivalent slab thickness; scale height

Signatures of Equatorial Plasma Bubbles and Ionospheric Scintillations from Magnetometer and GNSS Observations in the Indian Longitudes during the Space Weather Events of Early September 2017

Scintillation due to ionospheric plasma irregularities remains a challenging task for the space science community as it can severely threaten the dynamic systems relying on space-based navigation services. In the present paper, we probe the ionospheric current and plasma irregularity characteristics from a latitudinal arrangement of magnetometers and Global Navigation Satellite System (GNSS) stations from the equator to the far low latitude location over the Indian longitudes, during the severe space weather events of 6–10 ...

Vankadara, Ram; Panda, Sampad; Amory-Mazaudier, Christine; Fleury, Rolland; Devanaboyina, Venkata; Pant, Tarun; Jamjareegulgarn, Punyawi; Haq, Mohd; Okoh, Daniel; Seemala, Gopi;

Published by: Remote Sensing      Published on: jan

YEAR: 2022     DOI: 10.3390/rs14030652

space weather; equatorial plasma bubbles; ionospheric irregularity; global navigation satellite system; magnetometer; poleward drift; rate of change of TEC index; scintillations; storm-time electric currents

Signatures of Equatorial Plasma Bubbles and Ionospheric Scintillations from Magnetometer and GNSS Observations in the Indian Longitudes during the Space Weather Events of Early September 2017

Scintillation due to ionospheric plasma irregularities remains a challenging task for the space science community as it can severely threaten the dynamic systems relying on space-based navigation services. In the present paper, we probe the ionospheric current and plasma irregularity characteristics from a latitudinal arrangement of magnetometers and Global Navigation Satellite System (GNSS) stations from the equator to the far low latitude location over the Indian longitudes, during the severe space weather events of 6–10 ...

Vankadara, Ram; Panda, Sampad; Amory-Mazaudier, Christine; Fleury, Rolland; Devanaboyina, Venkata; Pant, Tarun; Jamjareegulgarn, Punyawi; Haq, Mohd; Okoh, Daniel; Seemala, Gopi;

Published by: Remote Sensing      Published on: jan

YEAR: 2022     DOI: 10.3390/rs14030652

space weather; equatorial plasma bubbles; ionospheric irregularity; global navigation satellite system; magnetometer; poleward drift; rate of change of TEC index; scintillations; storm-time electric currents



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