Data of the „ROMAP“-Magentometer aids in reconstruction of flight path
Just a little time after Rosetta lander „Philae“ touched down on a comet it was clear that the mission was not continuing as expected, because the lander bounced off the surface. The international team of scientists lead by geophysicist Dr. Uli Auster from the Institut für Geophysik und extraterrestische Physik was working at the „Philae“ control center at that time and followed the incredible flight of the lander.
The data obtained by the ROMAP magnetometer from Braunschweig immediatly showed the signatures of this bouncing and the subsequent touchdowns. With the data, the movement on the comet can be reconstructed.
Bounce: two hours above the comet
In the evening of 12th November, 2014, the scientists around Dr. Hans-Ulrich Auster were surprised when they saw the data of the ROMAP magnetometer immediately after touchdown: „With the magnetometer we can reconstuct the movement of the lander, just like the rotation of a compass needle. Consequently we could see instantly that „Philae“ bounced off the surface and finally returned after two hours. After evaluating our data we now have more information on the path to the final and still unknown landing site“ explained Dr. Auster.
Possible collision with a crater rim
Now the magnetic field data reveals that after the first touchdown „Philae“ started to rotate about its vertical axis, says Auster. The reason was that the reaction wheel, that was stabilizing the lander during descend, transferred its momentum to the freely moving lander. Within 40 minutes Philae accelerated to a rotational velocity of about 5 rpm, which is comparable to a wind turbine at low wind speeds“ says the geophysicist. But after 45 minutes the pattern changed suddenly: „The rotational velocity decreased to half the original speed, the axis tilted and the lander began to tumble. Most likely the reason was a collision with a crater rim“ summarized Dr. Auster.
Second landing decides Philae's fate
The magnetometer from Braunschweig shows that the lander tumbled above the surface for another hour before it jarringly touched down for the second time. „Then the fate of the lander was decided, which was also visible in magnetic field signatures. After first grazing the surface, „Philae“ landed on its feet at the last moment. After another seven minute bounce the lander arrived at its final position surrounded by icy walls“ say Hans-Ulrich Auster. „Although there was some luck involved, the astonishing landing impressively demonstrated that the lander was sturdy enough to not only withstand the harsh environmental conditions of space but also managed to survive this arduous landing sequence.”
The Rosetta Lander Magnetometer and Plasma Monitor (ROMAP) is one of ten instruments on the lander „Philae“, that investigates the magnetic field and solar wind parameters of the comet 67P/Churyumov-Gerasimenko for the ESA Mission Rosetta. Lead by Dr. Hans-Ulrich Auster of the Institut für Geophysik und extraterrestrische Physik at Technische Universität Braunschweig scientists from the Energy Research center in Budapest, the Institut für Weltraumforschung Graz in Austria and the Max-Planck Institut für Sonnensystemforschung in Göttingen contribute.
Dr. Hans-Ulrich Auster
Institut für Geophysik und extraterrestrische Physik
Technische Universität Braunschweig
Tel.: 0531 391-5241
Stephan Nachtigall | idw - Informationsdienst Wissenschaft
Study offers new theoretical approach to describing non-equilibrium phase transitions
27.04.2017 | DOE/Argonne National Laboratory
SwRI-led team discovers lull in Mars' giant impact history
26.04.2017 | Southwest Research Institute
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
27.04.2017 | Life Sciences
27.04.2017 | Physics and Astronomy
27.04.2017 | Earth Sciences