Drag balance Cubesat attitude motion effects on in-situ thermosphere density measurements

Abstract. The electron density profiles derived from the EFW and WHISPER instruments on board the four Cluster spacecraft reveal density structures inside the plasmasphere and at its outer boundary, the plasmapause. We have conducted a statistical study to characterize these density structures. We focus on the plasmasphere crossing on 11 April 2002, during which Cluster observed several density irregularities inside the plasmasphere, as well as a plasmaspheric plume. We derive the density gradient vectors from simultaneous density measurements by the four spacecraft. We also determine the normal velocity of the boundaries of the plume and of the irregularities from the time delays between those boundaries in the four individual density profiles, assuming they are planar. These new observations yield novel insights about the occurrence of density irregularities, their geometry and their dynamics. These in-situ measurements are compared with global images of the plasmasphere from the EUV imager on board the IMAGE satellite.

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Stratification observed by the in situ plasma density measurements from the Swarm satellites

Annales Geophysicae ◽

10.5194/angeo-38-517-2020 ◽

2020 ◽

Vol 38 (2) ◽

pp. 517-526

Author(s):

Xiuying Wang ◽

Wanli Cheng ◽

Zihan Zhou ◽

Dehe Yang ◽

Jing Cui ◽

...

Keyword(s):

Plasma Density ◽

Continuous Distribution ◽

Direct Analysis ◽

Density Measurements ◽

Equatorial Ionization Anomaly ◽

Swarm Satellites ◽

Plasma Peak ◽

First Time ◽

New Discovery

Abstract. The stratification phenomenon is investigated using the simultaneous in situ plasma density measurements obtained by the Swarm satellites orbiting at different altitudes above the F2 peak. For the first time, the continuous distribution morphology and the exact locations are obtained for the nighttime stratification, which show that the stratification events are centered at the EIA (equatorial ionization anomaly) trough and extend towards the two EIA crests, with the most significant part being located at the EIA trough. Another new discovery is the stratification in southern mid-latitudes; stratification events in this region are located on a local plasma peak sandwiched by two lower density strips covering all the longitudes. The formation mechanism of the stratification for the two latitudinal regions is discussed, but the stratification mechanism in southern mid-latitudes remains an unsolved problem. Highlights. This paper addresses the following: first application of in situ plasma densities for the direct analysis of the stratification in F2 layer, refined features of the exact location and continuous morphology for the stratification phenomenon, a new discovery of stratification covering all longitudes in southern mid-latitudes.

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Stratification observed by the in situ measurements from the Swarm satellites

10.5194/angeo-2019-161 ◽

2020 ◽

Author(s):

Xiuying Wang ◽

Wanli Cheng ◽

Zihan Zhou ◽

Dehe Yang ◽

Jing Cui ◽

...

Keyword(s):

Unsolved Problem ◽

Continuous Distribution ◽

Density Measurements ◽

Equatorial Ionization Anomaly ◽

Swarm Satellites ◽

Plasma Peak ◽

First Time ◽

Different Altitudes ◽

New Discovery

Abstract. Stratification phenomenon is investigated using the simultaneous in situ plasma density measurements obtained by the Swarm satellites orbiting at different altitudes above F2 peak. For the first time, the continuous distribution morphology and the exact locations are obtained for the nighttime stratification, which show that the stratification events are centered at the EIA (equatorial ionization anomaly) trough and extend towards the two EIA crests with the most significant part being located at the EIA trough. Another new discovery is the stratification in southern mid-latitudes; stratification events in this region are located on a local plasma peak sandwiched by two lower density strips covering all the longitudes. The formation mechanism of the stratification for the two latitudinal regions is discussed, but the stratification mechanism in southern mid-latitudes remains an unsolved problem.

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Preliminary validation of in situ electron density measurements onboard CSES using observations from Swarm Satellites

Advances in Space Research ◽

10.1016/j.asr.2019.05.025 ◽

2019 ◽

Vol 64 (4) ◽

pp. 982-994 ◽

Cited By ~ 3

Author(s):

Xiuying Wang ◽

Wanli Cheng ◽

Dehe Yang ◽

Dapeng Liu

Keyword(s):

Electron Density ◽

Density Measurements ◽

Preliminary Validation ◽

Swarm Satellites

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The first in situ electron temperature and density measurements of the Martian nightside ionosphere

Geophysical Research Letters ◽

10.1002/2015gl065267 ◽

2015 ◽

Vol 42 (21) ◽

pp. 8854-8861 ◽

Cited By ~ 29

Author(s):

C. M. Fowler ◽

L. Andersson ◽

R. E. Ergun ◽

M. Morooka ◽

G. Delory ◽

...

Keyword(s):

Electron Temperature ◽

Density Measurements

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Greenland annual accumulation along the EGIG line, 1959–2004, from ASIRAS airborne radar and detailed neutron-probe density measurements

The Cryosphere Discussions ◽

10.5194/tcd-9-6791-2015 ◽

2015 ◽

Vol 9 (6) ◽

pp. 6791-6828

Author(s):

T. B. Overly ◽

R. L. Hawley ◽

V. Helm ◽

E. M. Morris ◽

R. N. Chaudhary

Keyword(s):

Mesoscale Model ◽

Snow Accumulation ◽

Accumulation Rates ◽

Radar Altimeter ◽

Density Profiles ◽

Density Measurements ◽

Fifth Generation ◽

Neutron Probe ◽

Airborne Sar

Abstract. We report annual snow accumulation rates from 1959 to 2004 along a 250 km segment of the Expéditions Glaciologiques Internationales au Groenland (EGIG) line across central Greenland using Airborne SAR/Interferometric Radar Altimeter System (ASIRAS) radar layers and detailed neutron-probe (NP) density profiles. ASIRAS-NP accumulation rates are not statistically different (C.I. 95 %) from in situ EGIG accumulation measurements from 1985 to 2004. Below 3000 m elevation, ASIRAS-NP increases by 20 % for the period 1995 to 2004 compared to 1985 to 1994. Above 3000 m elevation, accumulation increases by 13 % for 1995–2004 compared to 1985–1994. Model snow accumulation results from the calibrated Fifth Generation Mesoscale Model modified for polar climates (Polar MM5) underestimate mean annual accumulation by 16 % compared to ASIRAS-NP from 1985 to 2004. We test radar-derived accumulation rates sensitivity to density using modelled density profiles in place of detailed NP data. ASIRAS radar layers combined with Herron and Langway (1980) model density profiles (ASIRAS-HL) produce accumulation rates within 3.5 % of ASIRAS-NP estimates. We suggest using Herron and Langway (1980) density profiles to calibrate radar layers detected in dry snow regions of ice sheets lacking detailed in situ density measurements, such as those observed by the IceBridge campaign.

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In-situ density measurements in the mesosphere/lower thermosphere region with the TOTAL and CONE instruments

An Introduction to Space Instrumentation ◽

10.5047/aisi.001 ◽

2013 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Boris Strelnikov ◽

Markus Rapp ◽

Franz-Josef Lübkin

Keyword(s):

Lower Thermosphere ◽

Density Measurements

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Greenland annual accumulation along the EGIG line, 1959–2004, from ASIRAS airborne radar and neutron-probe density measurements

The Cryosphere ◽

10.5194/tc-10-1679-2016 ◽

2016 ◽

Vol 10 (4) ◽

pp. 1679-1694 ◽

Cited By ~ 17

Author(s):

Thomas B. Overly ◽

Robert L. Hawley ◽

Veit Helm ◽

Elizabeth M. Morris ◽

Rohan N. Chaudhary

Keyword(s):

Climate Models ◽

Regional Climate ◽

Regional Climate Models ◽

Snow Accumulation ◽

Accumulation Rates ◽

Radar Altimeter ◽

Density Profiles ◽

Density Measurements ◽

Neutron Probe

Abstract. We report annual snow accumulation rates from 1959 to 2004 along a 250 km segment of the Expéditions Glaciologiques Internationales au Groenland (EGIG) line across central Greenland using Airborne SAR/Interferometric Radar Altimeter System (ASIRAS) radar layers and high resolution neutron-probe (NP) density profiles. ASIRAS-NP-derived accumulation rates are not statistically different (95 % confidence interval) from in situ EGIG accumulation measurements from 1985 to 2004. ASIRAS-NP-derived accumulation increases by 20 % below 3000 m elevation, and increases by 13 % above 3000 m elevation for the period 1995 to 2004 compared to 1985 to 1994. Three Regional Climate Models (PolarMM5, RACMO2.3, MAR) underestimate snow accumulation below 3000 m by 16–20 % compared to ASIRAS-NP from 1985 to 2004. We test radar-derived accumulation rates sensitivity to density using modeled density profiles in place of NP densities. ASIRAS radar layers combined with Herron and Langway (1980) model density profiles (ASIRAS-HL) produce accumulation rates within 3.5 % of ASIRAS-NP estimates in the dry snow region. We suggest using Herron and Langway (1980) density profiles to calibrate radar layers detected in dry snow regions of ice sheets lacking detailed in situ density measurements, such as those observed by the Operation IceBridge campaign.

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