Finished Research Projects

Satellite Gravimetry

  • Multi-sensor Climatology onboard GRACE
    The thermosphere lies between the exosphere and the mesosphere. The temperature in this layer can reach up to 4,500 degrees Fahrenheit. The thickness of this layer is about 513 km [NASA, 2018]. The thermosphere is the top level of the Earth atmosphere, located from 100 to 1000 km altitude. At 100 km already, the air density is twelve orders of magnitude lower than at the Earth’s surface. However, the remaining air is enough to exert a significant force on satellites orbiting the Earth at low heights. This perturbation is mainly due to high orbital velocity of 7.5 km/s, and the proportional relation between the air drag and the square of the speed. Since the space-borne accelerometer could measure the total non-conservative accelerations acting on the satellites directly, the air drag component could be isolated with the help of solar and earth albedo radiation pressure models, then the atmospheric density can be estimated, which provides necessary data for making evaluation and improvement of the existing atmospheric models.
    Leaders: Prof. Dr.-Ing. Jakob Flury, Dr.-Ing. Akbar Shabanloui
    Year: 2018
    Lifespan: WiSe 2018/2019
  • European Gravity Service for Improved Emergency Management (EGSIEM)
    Massenänderungen, abgeleitet aus der Mission GRACE (Gravity Recovery And Climate Experiment), liefern grundlegende Einblicke in den globalen Wasserkreislauf der Erde. Änderungen in der kontinentalen Wasser-speicherung steuern den regionalen Wasserhaushalt und können in Extremfällen zu Überschwemmungen und Dürren führen. Das Ziel von EGSIEM ist, den Wasserkreislauf der Erde aus dem Weltall mit hoher zeitlicher und räumlicher Auflösung zu beobachten und vorherzusagen.
    Leaders: Prof. Dr.-Ing. Jakob Flury
    Team: Dr.-Ing. Akbar Shabanloui
    Year: 2015
    Sponsors: European Commission (EC)
    Lifespan: 2015-2017
  • Fusion of ranging, accelerometry, and attitude sensing in the multi-sensor system for laserinterferometric inter-satellite ranging (CRC 1128, B02)
    The quality of gravity field results obtained from GRACE and GRACE Follow-On inter-satellite ranging does not only depend on the ranging measurement accuracy. Equally important is the quality of the integration in the multi-sensor system consisting of inter-satellite ranging, GNSS orbit tracking, accelerometry, and attitude sensing, and the performance of this system as a whole. The system performance is influenced, e.g., by star camera attitude performance, by the characteristics of satellite pointing jitter coupling, by inaccurate knowledge and instabilities of phase centers and alignments, and by accelerometer signal disturbances.
    Leaders: Prof. Jakob Flury, Dr. Gerhard Heinzel
    Team: M.Sc. Santoshkumar Burla, Henry Wegener, Dr. Akbar Shabanloui
    Year: 2014
    Sponsors: DFG
    Lifespan: 2014-2018
  • System studies for an optical gradiometer mission (CRC 1128, B07)
    Leaders: Dr. Gerhard Heinzel, Prof. Dr.-Ing. habil. Jürgen Müller
    Team: Dr. Karim Douch, Brigitte Kaune, Dr. Akbar Shabanloui
    Year: 2014
    Sponsors: DFG

Space Sensor Technologies

  • Multi-sensor Climatology onboard GRACE
    The thermosphere lies between the exosphere and the mesosphere. The temperature in this layer can reach up to 4,500 degrees Fahrenheit. The thickness of this layer is about 513 km [NASA, 2018]. The thermosphere is the top level of the Earth atmosphere, located from 100 to 1000 km altitude. At 100 km already, the air density is twelve orders of magnitude lower than at the Earth’s surface. However, the remaining air is enough to exert a significant force on satellites orbiting the Earth at low heights. This perturbation is mainly due to high orbital velocity of 7.5 km/s, and the proportional relation between the air drag and the square of the speed. Since the space-borne accelerometer could measure the total non-conservative accelerations acting on the satellites directly, the air drag component could be isolated with the help of solar and earth albedo radiation pressure models, then the atmospheric density can be estimated, which provides necessary data for making evaluation and improvement of the existing atmospheric models.
    Leaders: Prof. Dr.-Ing. Jakob Flury, Dr.-Ing. Akbar Shabanloui
    Year: 2018
    Lifespan: WiSe 2018/2019

CRC 1128 (geo-Q)

  • Fusion of ranging, accelerometry, and attitude sensing in the multi-sensor system for laserinterferometric inter-satellite ranging (CRC 1128, B02)
    The quality of gravity field results obtained from GRACE and GRACE Follow-On inter-satellite ranging does not only depend on the ranging measurement accuracy. Equally important is the quality of the integration in the multi-sensor system consisting of inter-satellite ranging, GNSS orbit tracking, accelerometry, and attitude sensing, and the performance of this system as a whole. The system performance is influenced, e.g., by star camera attitude performance, by the characteristics of satellite pointing jitter coupling, by inaccurate knowledge and instabilities of phase centers and alignments, and by accelerometer signal disturbances.
    Leaders: Prof. Jakob Flury, Dr. Gerhard Heinzel
    Team: M.Sc. Santoshkumar Burla, Henry Wegener, Dr. Akbar Shabanloui
    Year: 2014
    Sponsors: DFG
    Lifespan: 2014-2018
  • System studies for an optical gradiometer mission (CRC 1128, B07)
    Leaders: Dr. Gerhard Heinzel, Prof. Dr.-Ing. habil. Jürgen Müller
    Team: Dr. Karim Douch, Brigitte Kaune, Dr. Akbar Shabanloui
    Year: 2014
    Sponsors: DFG

Project Seminar

  • Multi-sensor Climatology onboard GRACE
    The thermosphere lies between the exosphere and the mesosphere. The temperature in this layer can reach up to 4,500 degrees Fahrenheit. The thickness of this layer is about 513 km [NASA, 2018]. The thermosphere is the top level of the Earth atmosphere, located from 100 to 1000 km altitude. At 100 km already, the air density is twelve orders of magnitude lower than at the Earth’s surface. However, the remaining air is enough to exert a significant force on satellites orbiting the Earth at low heights. This perturbation is mainly due to high orbital velocity of 7.5 km/s, and the proportional relation between the air drag and the square of the speed. Since the space-borne accelerometer could measure the total non-conservative accelerations acting on the satellites directly, the air drag component could be isolated with the help of solar and earth albedo radiation pressure models, then the atmospheric density can be estimated, which provides necessary data for making evaluation and improvement of the existing atmospheric models.
    Leaders: Prof. Dr.-Ing. Jakob Flury, Dr.-Ing. Akbar Shabanloui
    Year: 2018
    Lifespan: WiSe 2018/2019
  • Globales Schwerefeld mittels GRACE High-Low-Satellite-to-Satellite-Tracking / Beschleunigungsansatz
    Die Modellierung des Schwerefeldes gehört zu den zentralen Aufgaben der physikalischen Geodäsie. Mit einem präzisen Schwerefeldmodell können beispielsweise Prozesse wie die postglaziale Landhebung, der Meeresspiegelanstieg oder Eismassenverluste global und quantitativ erfasst werden. Das Ziel dieses Projektseminars ist die Bestimmung eines Schwerefeldmodells für den Dezember 2008 unter Nutzung der Daten von GRACE. Hier werden jedoch nicht die Abstandsdaten des Interferometers genutzt, sondern die Satelliten werden als freifallende Körper betrachtet.
    Leaders: Prof. Dr.-Ing. Jakob Flury, Dr.-Ing. Akbar Shabanloui, Dr.-Ing. Majid Naeimi, M.Sc. Christoph Wallat
    Year: 2016
    Lifespan: WiSe 2016 - SoSe 2017
  • Präzise Satellitenbahnmodellierung am Beispiel der neuen SWARM-Mission
    Aktuell werden Satelliten in vielen wissenschaftlichen Disziplinen verwendet. Besonders bei der Bestimmung des Erdschwerefeldes ist es wichtig, den Satellitenorbit präzise zu kennen. In diesem Projektseminar wurde eine Software zur Modellierung und numerischen Integration von LEO-Bahnen in MATLAB implementiert und anhand eines Beispielsorbits der ESA-Mission „Swarm“ getestet.
    Leaders: Prof. Dr.-Ing. Jakob Flury, Dr.-Ing. Akbar Shabanloui, Dr.-Ing. Majid Naeimi, Dr.-Ing. Manuel Schilling
    Team: Peter Alpers, Mahsa Bashi, Igor Koch, Damian Kröhnert
    Year: 2015
    Lifespan: WiSe 2015 - SoSe 2016
  • Ultrapräzise Messungen in der GOCE-Wiedereintrittsphase
    Der Beginn der Wiedereintrittsphase des GOCE-Satelliten wurde durch das Abschalten des Ionentriebwerkes am 21.10.2013 gestartet. Das Ende der Wiedereintrittsphase wurde durch das Verglühen des GOCE-Satelliten in der Erdatmosphäre, über den Falkland-Inseln, am 11.11.2013 markiert. Im Rahmen der Arbeit wurden verschiedene Bereiche der Wiedereintrittsphase untersucht.
    Leaders: Prof. Dr.-Ing. Jakob Flury, Dr.-Ing. Akbar Shabanloui, Dr.-Ing. Majid Naeimi
    Year: 2014
    Lifespan: WiSe 2014 - SoSe 2015