Research

Cassini-Huygens ISS

Jul 01, 2015 — Oct 31, 2018

Journeys to planets and moons of the Outer Solar System always pose a great challenge to space-mission design and conduct. Within the framework of the Cassini-Huygens mission US and European space agencies jointly succeeded in sending a probe and a lander to the Saturnian system, over 1 billion kilometers away. Since 2004, instruments aboard the Cassini spacecraft continuously collect scientific data and transmit spectacular and astonishing new views to Earth. Scientists of the Planetary Sciences and Remote Sensing Group at FU Berlin are involved in the Cassini camera experiment, the Imaging Science Subsystem (ISS).    View from moon Iapetus to Saturn (Image Credit: NASA/JPL/Space Science Institute)     The international Cassini-Huygens mission is a joint project of NASA, ESA and ASI, the Italian Space Agency. While NASA already successfully sent the Pioneer and Voyager probes to the Saturnian system between 1979 and 1981, Huygens, the landing capsule built by ESA, has been the first European contribution to a space mission to the Outer Solar System. Cassini-Huygens was launched 1997 in Cape Canaveral, Florida and reached the orbit of the second largest planet of our solar system in 2004, after a journey of nearly 7 years and 3.5 billion kilometers. In December 2004, the Huygens landing capsule was released from the Cassini orbiter. One month later, Huygens successfully landed on the largest Saturnian moon Titan. Cassini itself orbits Saturn to this day and on its journey it investigates the magnetosphere of the planet as well as its rings and moons, of which to date over 60 have been discovered. On board the Cassini orbiter we can find amongst others the Imaging Science Subsystem (ISS), a camera for images within the spectral range of the near-ultraviolet (UV), the visible light and the near-infrared (NIR). In cooperation with the German Aerospace Center (DLR) in Berlin-Adlershof and supported by the National Space Administration, the Planetary Sciences and Remote Sensing Group at FU Berlin is engaged in the planning and evaluation of image data of the Saturnian moons. The mission, originally planned to last until 2008, was already extended twice and is now due to end in September 2017. Thus there is time for numerous more observations and investigations into the Saturnian system. The researches have exclusive data rights for about one year until the image data is archived by the Planetary Data System (PDS) of NASA and made available to the public. Link to mission participation of the Planetary Sciences and Remote Sensing Group.

Dawn

Nov 01, 2015 — Jul 31, 2018

Since its takeoff from Cape Canaveral, Florida, on September 27, 2007, the US space probe Dawn is on its mission to explore the small bodies Vesta and Ceres in the asteroid belt between Mars and Jupiter. The NASA-mission aims at investigating the formation and evolution of these bodies to find clues to the solar system’s early history. The journey through the inner solar system, in the course of which Mars was passed in February 2009, was successfully completed by Dawn and in July 2011 its first target, the asteroid Vesta, was reached. For a year, the probe collected scientific data of Vesta before starting the journey for two and a half years to its second mission object, the dwarf planet Ceres. At the beginning of 2015 the probe has reached the target; since then the instruments continuously transmit data about the properties of Ceres, while further approaching its surface.     Space probe Dawn approaching Vesta (artist's impression) Image Credit: NASA/JPL-Caltech     The camera experiment on board Dawn is the Framing Camera (FC) which was developed in cooperation between the Max Planck Institute for Solar System Research and the German Aerospace Center (DLR). The Planetary Sciences and Remote Sensing Group of FU Berlin is involved in the scientific processing and evaluation of the image data. In Dawn’s lowest orbit, at an altitude of about 210 km, it was possible to get shoots of Vesta’s surface with a resolution of up to 20 m per pixel. Vesta’s surface was nearly completely covered by the camera in the course of the spacecraft’s one-year-long sojourn. The combination of the Framing Camera data with that of the Visible and Infrared Spectrometer (VIR) and the Gamma Ray and Neutron Detector (GRaND) constitutes a significant basis for the understanding of the planetoids evolution. It enables insights into the early history of the solar system and thereby into that of the Earth. One of the main tasks of the research group at FU Berlin consists in developing a chronostratigraphic system. The dating of different landforms by determining the frequency distribution of crater size provides the scientists with important information to better understand the geological evolution and impact processes on Vesta. The detailed insight into meteorite impacts on Vesta makes it possible to much better establish corresponding coherences with the evolution of meteorite impacts in the young solar system. Of special interest in this case is also the examination of the material distribution of rock forming minerals and water ice. On behalf of the Dawn Science Team the researchers at FU Berlin create geologic maps and dating of Vesta’s surface. In April 2015 the probe has arrived at Ceres, the largest body in the asteroid belt (with dimensions of 487 km x 455 km), and collected first scientific data with a resolution of about one kilometer per pixel. Currently the probe is located in the final survey orbit at an altitude of less than 400 km above the surface and takes images with a resolution of up to 30 meters per pixel. Link to mission participation of the Planetary Sciences and Remote Sensing Group.   

Mars Express im Orbit

HRSC on Mars Express

Jan 01, 2017 — Dec 31, 2019

Mars Express is the first European mission to Mars. Since its arrival in 2003, the experiments aboard the spacecraft have provided important clues on surface geology and morphology, the subsurface, the atmosphere, the history of water and the question of life. One experiment on the spacecraft is the High Resolution Stereo Camera (HRSC) which aims at global multispectral and three-dimensional coverage of the Martian surface with a resolution of up to 10 meters per pixel. To date, about 75% of the Martian surface has been covered in 3-D. ESA’s space probe Mars Express was launched on June 2, 2003 by a Soyuz-Fregat rocket from Baikonur Cosmodrome in Kazakhstan. On December 25, 2003, it entered the orbit of Mars. The orbit of Mars Express itself is elliptical with a maximum distance of 10 530 km over the Martian surface and 330 km at closest approach. This geometry allows for observations of the Mars moons Phobos and Deimos as well as for atmospheric profile measurements. The following European instruments are found on board Mars Express: HRSC, a high-resolution stereo camera for 3-D color mapping of the planet’s surface, MARSIS; a radar altimeter to examine the planet’s subsurface structure, the Fourier spectrometer PFS, investigating the composition of the atmosphere, the hyperspectral spectrometer OMEGA, observing the planet’s mineralogy in the visible and infrared range, ASPERA, a device for plasma analysis and MaRS, a radio experiment. Link to the mission participation of the Planetary Sciences and Remote Sensing Group.

SFB Transregio 170

Jan 01, 2016 — Dec 31, 2019

Subproject A3 “Ancient bombardment of the inner solar system – Reinvestigation of the ‘fingerprints’ of different impactor populations” In the Collaborative Research Centre „Late Accretion onto Terrestrial Planets“, scientists from five institutions (Freie Universität Berlin, Technische Universität Berlin, University of Münster, German Aerospace Center, Museum für Naturkunde) investigate the late accretion history of planetary bodies in the inner solar system from 4.5 to 3.8 billion years ago. The Planetary Sciences and Remote Sensing research group at Freie Universität Berlin is involved in one of the 16 subprojects. This subproject A3 “Ancient bombardment of the inner solar system – Reinvestigation of the ‘fingerprints’ of different impactor populations, is focused on the lunar cratering record and analyses based on crater size-frequency distributions (CSFDs). Although CSFDs are widely used for relative and absolute age determinations of lunar surfaces, it is still not clear if there was more than one impactor population involved in the formation of the Moon’s cratering record during the late accretion period. Since current methodologies for dating lunar surfaces assume there was only one population, i.e., the origin of impacting projectiles remained constant, a combination of different populations would influence the age determination results significantly. In subproject A3, we thus conduct detailed geological mapping and crater size-frequency measurements in combination with new approaches of GIS spatial analyses to investigate the shapes of CSFDs and to validate the suitability of regions which were previously used for this purpose. Altogether, this will help to improve the methods of CSFD-based age determination, to examine a potential time-variable lunar crater production function and to further understand the late accretion history of planetary bodies in the inner solar system.           Crater counting area on the lunar surface (left), Lunar Reconnaissance Orbiter Camera (LROC) image, and the corresponding crater size-frequency distribution (right). Green box shows the deviation of the measured impact crater distribution from the assumed production function, which is the object of investigation of the subproject A3.       Participants in the SFB Transregio 170 project team Dr. Gregory Michael(main contact) Project Coordinator Csilla Orgel Analysis of crater distributions Christian Riedel Analysis of crater distributions, Software development