TY - CHAP A1 - Loeb, Horst Wolfgang A1 - Schartner, Karl-Heinz A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang T1 - SEP-Sample return from a main belt asteroid T2 - 30th International Electric Propulsion Conference N2 - By DLR-contact, sample return missions to the large main-belt asteroid “19, Fortuna” have been studied. The mission scenario has been based on three ion thrusters of the RIT-22 model, which is presently under space qualification, and on solar arrays equipped with triple-junction GaAs solar cells. After having designed the spacecraft, the orbit-to-orbit trajectories for both, a one-way SEP mission with a chemical sample return and an all-SEP return mission, have been optimized using a combination of artificial neural networks with evolutionary algorithms. Additionally, body-to-body trajectories have been investigated within a launch period between 2012 and 2015. For orbit-to-orbit calculation, the launch masses of the hybrid mission and of the all-SEP mission resulted in 2.05 tons and 1.56 tons, respectively, including a scientific payload of 246 kg. For the related transfer durations 4.14 yrs and 4.62 yrs were obtained. Finally, a comparison between the mission scenarios based on SEP and on NEP have been carried out favouring clearly SEP. Y1 - 2007 SP - 1 EP - 11 ER - TY - CHAP A1 - Dachwald, Bernd A1 - Ohndorf, Andreas A1 - Spurmann, J. A1 - Loeb, H. W. A1 - Schartner, Karl-Heinz A1 - Seboldt, Wolfgang T1 - Mission design for a SEP mission to saturn T2 - 60th International Astronautical Congress 2009 (IAC 2009) N2 - Within ESA's Cosmic Vision 2015-2025 plan, a mission to explore the Saturnian System, with special emphasis on its two moons Titan and Enceladus, was selected for study, termed TANDEM (Titan and Enceladus Mission). In this paper, we describe an optimized mission design for a TANDEM-derived solar electric propulsion (SEP) mission. We have chosen the SEP mission scenario for the interplanetary transfer of the TANDEM spacecraft because all feasible gravity assist sequences for a chemical transfer between 2015 and 2025 result in long flight times of about nine years. Our SEP system is based on the German RIT ion engine. For our optimized mission design, we have extensively explored the SEP parameter space (specific impulse, thrust level, power level) and have calculated an optimal interplanetary trajectory for each setting. In contrast to the original TANDEM mission concept, which intends to use two launch vehicles and an all-chemical transfer, our SEP mission design requires only a single Ariane 5 ECA launch for the same payload mass. Without gravity assist, it yields a faster and more flexible transfer with a fight time of less than seven years, and an increased payload ratio. Our mission design proves thereby the capability of SEP even for missions into the outer solar system. Y1 - 2009 SN - 978-1-61567-908-9 N1 - 12-16 October 2009, Daejeon, Republic of Korea. PB - Curran Associates, Inc. CY - Red Hook, NY ER - TY - CHAP A1 - Dachwald, Bernd A1 - Wurm, P. T1 - Design concept and modeling of an advanced solar photon thruster T2 - Advances in the Astronautical Sciences N2 - The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), holds the potential of providing significant performance advantages over the flat solar sail. Previous SPT design concepts, however, do not consider shadowing effects and multiple reflections of highly concentrated solar radiation that would inevitably destroy the gossamer sail film. In this paper, we propose a novel advanced SPT (ASPT) design concept that does not suffer from these oversimplifications. We present the equations that describe the thrust force acting on such a sail system and compare its performance with respect to the conventional flat solar sail. KW - solar sails Y1 - 2009 SN - 978-087703554-1 SN - 00653438 N1 - 19th AAS/AIAA Space Flight Mechanics Meeting; Savannah, GA; United States; 8 February 2009 through 12 February 2009 SP - 723 EP - 740 PB - American Astronautical Society CY - San Diego, Calif. ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Biele, Jens A1 - Dachwald, Bernd A1 - Grimm, Christian D. A1 - Lange, Caroline A1 - Ulamec, Stephan A1 - Ziach, Christian A1 - Spröwitz, Tom A1 - Ruffer, Michael A1 - Seefeldt, Patric A1 - Spietz, Peter A1 - Toth, Norbert A1 - Mimasu, Yuya A1 - Rittweger, Andreas A1 - Bibring, Jean-Pierre A1 - Braukhane, Andy A1 - Boden, Ralf Christian A1 - Dumont, Etienne A1 - Jahnke, Stephan Siegfried A1 - Jetzschmann, Michael A1 - Krüger, Hans A1 - Lange, Michael A1 - Gomez, Antonio Martelo A1 - Massonett, Didier A1 - Okada, Tatsuaki A1 - Sagliano, Marco A1 - Sasaki, Kaname A1 - Schröder, Silvio A1 - Sippel, Martin A1 - Skoczylas, Thomas A1 - Wejmo, Elisabet T1 - Small landers and separable sub-spacecraft for near-term solar sails T2 - The Fourth International Symposium on Solar Sailing 2017 N2 - Following the successful PHILAE landing with ESA's ROSETTA probe and the launch of the MINERVA rovers and the Mobile Asteroid Surface Scout, MASCOT, aboard the JAXA space probe, HAYABUSA2, to asteroid (162173) Ryugu, small landers have found increasing interest. Integrated at the instrument level in their mothership they support small solar system body studies. With efficient capabilities, resource-friendly design and inherent robustness they are an attractive exploration mission element. We discuss advantages and constraints of small sub-spacecraft, focusing on emerging areas of activity such as asteroid diversity studies, planetary defence, and asteroid mining, on the background of our projects PHILAE, MASCOT, MASCOT2, the JAXA-DLR Solar Power Sail Lander Design Study, and others. The GOSSAMER-1 solar sail deployment concept also involves independent separable sub-spacecraft operating synchronized to deploy the sail. Small spacecraft require big changes in the way we do things and occasionally a little more effort than would be anticipated based on a traditional large spacecraft approach. In a Constraints-Driven Engineering environment we apply Concurrent Design and Engineering (CD/CE), Concurrent Assembly, Integration and Verification (CAIV) and Model-Based Systems Engineering (MBSE). Near-term solar sails will likely be small spacecraft which we expect to harmonize well with nano-scale separable instrument payload packages. KW - Small Solar System Body Lander KW - Small Spacecraft KW - PHILAE KW - MASCOT KW - Solar Power Sail Y1 - 2017 N1 - The Fourth International Symposium on Solar Sailing 2017, 17-20 January 2017. Kyoto Research Park, Kyoto, Japan SP - 1 EP - 10 ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Bauer, Waldemar A1 - Boden, Ralf A1 - Ceriotti, Matteo A1 - Chand, Suditi A1 - Cordero, Federico A1 - Dachwald, Bernd A1 - Dumont, Etienne A1 - Grimm, Christian D. A1 - Heiligers, Jeannette A1 - Herčík, David A1 - Hérique, Alain A1 - Ho, Tra-Mi A1 - Jahnke, Rico A1 - Kofman, Wlodek A1 - Lange, Caroline A1 - Lichtenheldt, Roy A1 - McInnes, Colin A1 - Meß, Jan-Gerd A1 - Mikschl, Tobias A1 - Mikulz, Eugen A1 - Montenegro, Sergio A1 - Moore, Iain A1 - Pelivan, Ivanka A1 - Peloni, Alessandro A1 - Plettemeier, Dirk A1 - Quantius, Dominik A1 - Reershemius, Siebo A1 - Renger, Thomas A1 - Riemann, Johannes A1 - Rogez, Yves A1 - Ruffer, Michael A1 - Sasaki, Kaname A1 - Schmitz, Nicole A1 - Seboldt, Wolfgang A1 - Seefeldt, Patric A1 - Spietz, Peter A1 - Spröwitz, Tom A1 - Sznajder, Maciej A1 - Tóth, Norbert A1 - Vergaaij, Merel A1 - Viavattene, Giulia A1 - Wejmo, Elisabet A1 - Wiedemann, Carsten A1 - Wolff, Friederike A1 - Ziach, Christian T1 - Flights are ten a sail – Re-use and commonality in the design and system engineering of small spacecraft solar sail missions with modular hardware for responsive and adaptive exploration T2 - 70th International Astronautical Congress (IAC) KW - system engineering KW - small solar system body characterisation KW - small spacecraft solar sail KW - small spacecraft asteroid lander KW - responsive space Y1 - 2019 SN - 9781713814856 N1 - 70th International Astronautical Congress (IAC), Washington D.C., United States, 21-25 October 2019 SP - 1 EP - 7 ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Bauer, Waldemar A1 - Boden, Ralf Christian A1 - Ceriotti, Matteo A1 - Cordero, Federico A1 - Dachwald, Bernd A1 - Dumont, Etienne A1 - Grimm, Christian D. A1 - Hercik, D. A1 - Herique, A. A1 - Ho, Tra-Mi A1 - Jahnke, Rico A1 - Kofman, Wlodek A1 - Lange, Caroline A1 - Lichtenheldt, Roy A1 - McInnes, Colin R. A1 - Mikschl, Tobias A1 - Mikulz, Eugen A1 - Montenegro, Sergio A1 - Moore, Iain A1 - Pelivan, Ivanka A1 - Peloni, Alessandro A1 - Plettemeier, Dirk A1 - Quantius, Dominik A1 - Reershemius, Siebo A1 - Renger, Thomas A1 - Riemann, Johannes A1 - Rogez, Yves A1 - Ruffer, Michael A1 - Sasaki, Kaname A1 - Schmitz, Nicole A1 - Seboldt, Wolfgang A1 - Seefeldt, Patric A1 - Spietz, Peter A1 - Spröwitz, Tom A1 - Sznajder, Maciej A1 - Toth, Norbert A1 - Viavattene, Giulia A1 - Wejmo, Elisabet A1 - Wolff, Friederike A1 - Ziach, Christian T1 - Responsive integrated small spacecraft solar sail and payload design concepts and missions T2 - Conference: 5th International Symposium on Solar Sailing (ISSS 2019) N2 - Asteroid mining has the potential to greatly reduce the cost of in-space manufacturing, production of propellant for space transportation and consumables for crewed spacecraft, compared to launching the required resources from Earth’s deep gravity well. This paper discusses the top-level mission architecture and trajectory design for these resource-return missions, comparing high-thrust trajectories with continuous low-thrust solar-sail trajectories. This work focuses on maximizing the economic Net Present Value, which takes the time-cost of finance into account and therefore balances the returned resource mass and mission duration. The different propulsion methods will then be compared in terms of maximum economic return, sets of attainable target asteroids, and mission flexibility. This paper provides one more step towards making commercial asteroid mining an economically viable reality by integrating trajectory design, propulsion technology and economic modelling. Y1 - 2019 N1 - Conference: 5th International Symposium on Solar Sailing (ISSS 2019)At: Aachen, Germany ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Meß, Jan-Gerd A1 - Biele, Jens A1 - Seefeldt, Patric A1 - Dachwald, Bernd A1 - Spietz, Peter A1 - Grimm, Christian D. A1 - Spröwitz, Tom A1 - Lange, Caroline A1 - Ulamec, Stephan T1 - Small spacecraft in small solar system body applications T2 - IEEE Aerospace Conference 2017, Big Sky, Montana, USA Y1 - 2017 SN - 978-1-5090-1613-6 U6 - https://doi.org/10.1109/AERO.2017.7943626 SP - 1 EP - 20 ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Borella, Laura A1 - Ceriotti, Matteo A1 - Chand, Suditi A1 - Cordero, Federico A1 - Dachwald, Bernd A1 - Fexer, Sebastian A1 - Grimm, Christian D. A1 - Hendrikse, Jeffrey A1 - Herčík, David A1 - Herique, Alain A1 - Hillebrandt, Martin A1 - Ho, Tra-Mi A1 - Kesseler, Lars A1 - Laabs, Martin A1 - Lange, Caroline A1 - Lange, Michael A1 - Lichtenheldt, Roy A1 - McInnes, Colin R. A1 - Moore, Iain A1 - Peloni, Alessandro A1 - Plettenmeier, Dirk A1 - Quantius, Dominik A1 - Seefeldt, Patric A1 - Venditti, Flaviane c. F. A1 - Vergaaij, Merel A1 - Viavattene, Giulia A1 - Virkki, Anne K. A1 - Zander, Martin T1 - More bucks for the bang: new space solutions, impact tourism and one unique science & engineering opportunity at T-6 months and counting T2 - 7th IAA Planetary Defense Conference N2 - For now, the Planetary Defense Conference Exercise 2021's incoming fictitious(!), asteroid, 2021 PDC, seems headed for impact on October 20th, 2021, exactly 6 months after its discovery. Today (April 26th, 2021), the impact probability is 5%, in a steep rise from 1 in 2500 upon discovery six days ago. We all know how these things end. Or do we? Unless somebody kicked off another headline-grabbing media scare or wants to keep civil defense very idle very soon, chances are that it will hit (note: this is an exercise!). Taking stock, it is barely 6 months to impact, a steadily rising likelihood that it will actually happen, and a huge uncertainty of possible impact energies: First estimates range from 1.2 MtTNT to 13 GtTNT, and this is not even the worst-worst case: a 700 m diameter massive NiFe asteroid (covered by a thin veneer of Ryugu-black rubble to match size and brightness), would come in at 70 GtTNT. In down to Earth terms, this could be all between smashing fireworks over some remote area of the globe and a 7.5 km crater downtown somewhere. Considering the deliberate and sedate ways of development of interplanetary missions it seems we can only stand and stare until we know well enough where to tell people to pack up all that can be moved at all and save themselves. But then, it could just as well be a smaller bright rock. The best estimate is 120 m diameter from optical observation alone, by 13% standard albedo. NASA's upcoming DART mission to binary asteroid (65803) Didymos is designed to hit such a small target, its moonlet Dimorphos. The Deep Impact mission's impactor in 2005 successfully guided itself to the brightest spot on comet 9P/Tempel 1, a relatively small feature on the 6 km nucleus. And 'space' has changed: By the end of this decade, one satellite communication network plans to have launched over 11000 satellites at a pace of 60 per launch every other week. This level of series production is comparable in numbers to the most prolific commercial airliners. Launch vehicle production has not simply increased correspondingly – they can be reused, although in a trade for performance. Optical and radio astronomy as well as planetary radar have made great strides in the past decade, and so has the design and production capability for everyday 'high-tech' products. 60 years ago, spaceflight was invented from scratch within two years, and there are recent examples of fast-paced space projects as well as a drive towards 'responsive space'. It seems it is not quite yet time to abandon all hope. We present what could be done and what is too close to call once thinking is shoved out of the box by a clear and present danger, to show where a little more preparedness or routine would come in handy – or become decisive. And if we fail, let's stand and stare safely and well instrumented anywhere on Earth together in the greatest adventure of science. Y1 - 2021 N1 - 7th IAA Planetary Defense Conference, Vienna, Austria, 26-30 April 2021 ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Bauer, Wlademar A1 - Borchers, Kai A1 - Dumont, Etienne A1 - Grimm, Christian D. A1 - Ho, Tra-Mi A1 - Jahnke, Rico A1 - Koch, Aaron D. A1 - Lange, Caroline A1 - Maiwald, Volker A1 - Meß, Jan-Gerd A1 - Mikulz, Eugen A1 - Quantius, Dominik A1 - Reershemius, Siebo A1 - Renger, Thomas A1 - Sasaki, Kaname A1 - Seefeldt, Patric A1 - Spietz, Peter A1 - Spröwitz, Tom A1 - Sznajder, Maciej A1 - Toth, Norbert A1 - Ceriotti, Matteo A1 - McInnes, Colin A1 - Peloni, Alessandro A1 - Biele, Jens A1 - Krause, Christian A1 - Dachwald, Bernd A1 - Hercik, David A1 - Lichtenheldt, Roy A1 - Wolff, Friederike A1 - Koncz, Alexander A1 - Pelivan, Ivanka A1 - Schmitz, Nicole A1 - Boden, Ralf A1 - Riemann, Johannes A1 - Seboldt, Wolfgang A1 - Wejmo, Elisabet A1 - Ziach, Christian A1 - Mikschl, Tobias A1 - Montenegro, Sergio A1 - Ruffer, Michael A1 - Cordero, Federico A1 - Tardivel, Simon T1 - Solar sails for planetary defense & high-energy missions T2 - IEEE Aerospace Conference Proceedings N2 - 20 years after the successful ground deployment test of a (20 m) 2 solar sail at DLR Cologne, and in the light of the upcoming U.S. NEAscout mission, we provide an overview of the progress made since in our mission and hardware design studies as well as the hardware built in the course of our solar sail technology development. We outline the most likely and most efficient routes to develop solar sails for useful missions in science and applications, based on our developed `now-term' and near-term hardware as well as the many practical and managerial lessons learned from the DLR-ESTEC Gossamer Roadmap. Mission types directly applicable to planetary defense include single and Multiple NEA Rendezvous ((M)NR) for precursor, monitoring and follow-up scenarios as well as sail-propelled head-on retrograde kinetic impactors (RKI) for mitigation. Other mission types such as the Displaced L1 (DL1) space weather advance warning and monitoring or Solar Polar Orbiter (SPO) types demonstrate the capability of near-term solar sails to achieve asteroid rendezvous in any kind of orbit, from Earth-coorbital to extremely inclined and even retrograde orbits. Some of these mission types such as SPO, (M)NR and RKI include separable payloads. For one-way access to the asteroid surface, nanolanders like MASCOT are an ideal match for solar sails in micro-spacecraft format, i.e. in launch configurations compatible with ESPA and ASAP secondary payload platforms. Larger landers similar to the JAXA-DLR study of a Jupiter Trojan asteroid lander for the OKEANOS mission can shuttle from the sail to the asteroids visited and enable multiple NEA sample-return missions. The high impact velocities and re-try capability achieved by the RKI mission type on a final orbit identical to the target asteroid's but retrograde to its motion enables small spacecraft size impactors to carry sufficient kinetic energy for deflection. Y1 - 2019 U6 - https://doi.org/10.1109/AERO.2019.8741900 N1 - AERO 2019; Big Sky; United States; 2 March 2019 through 9 March 2019 SP - 1 EP - 21 ER - TY - CHAP A1 - Grundmann, Jan Thimo A1 - Lange, Caroline A1 - Dachwald, Bernd A1 - Grimm, Christian A1 - Koch, Aaron A1 - Ulamec, Stephan T1 - Small Spacecraft in Planetary Defence Related Applications–Capabilities, Constraints, Challenges T2 - IEEE Aerospace Conference N2 - In this paper we present an overview of the characteristics and peculiarities of small spacecraft missions related to planetary defence applications. We provide a brief overview of small spacecraft missions to small solar system bodies. On this background we present recent missions and selected projects and related studies at the German Aerospace Center, DLR, that contribute to planetary defence related activities. These range from Earth orbit technology demonstrators to active science missions in interplanetary space. We provide a summary of experience from recently flown missions with DLR participation as well as a number of studies. These include PHILAE, the lander recently arrived on comet 67P/Churyumov-Gerasimenko aboard ESA’s ROSETTA comet rendezvous mission, and the Mobile Asteroid Surface Scout, MASCOT, now underway to near-Earth asteroid (162173) 1999 JU3 aboard the Japanese sample-return probe HAYABUSA-2. We introduce the differences between the conventional methods employed in the design, integration and testing of large spacecraft and the new approaches developed by small spacecraft projects. We expect that the practical experience that can be gained from projects on extremely compressed timelines or with high-intensity operation phases on a newly explored small solar system body can contribute significantly to the study, preparation and realization of future planetary defence related missions. One is AIDA (Asteroid Impact & Deflection Assessment), a joint effort of ESA,JHU/APL, NASA, OCA and DLR, combining JHU/APL’s DART (Double Asteroid Redirection Test) and ESA’s AIM (Asteroid Impact Monitor) spacecraft in a mission towards near-Eath binary asteroid (65803) Didymos. KW - small spacecraft KW - planetary defence KW - asteroid lander KW - solar sail KW - flotilla missions Y1 - 2015 N1 - 2015 IEEE Aerospace Conference, 7.-13. Mar. 2015, Big Sky, Montana, USA. SP - 1 EP - 18 ER - TY - CHAP A1 - Ohndorf, Andreas A1 - Dachwald, Bernd A1 - Seboldt, Wolfgang A1 - Schartner, Karl-Heinz T1 - Flight times to the heliopause using a combination of solar and radioisotope electric propulsion T2 - 32nd International Electric Propulsion Conference N2 - We investigate the interplanetary flight of a low-thrust space probe to the heliopause,located at a distance of about 200 AU from the Sun. Our goal was to reach this distance within the 25 years postulated by ESA for such a mission (which is less ambitious than the 15-year goal set by NASA). Contrary to solar sail concepts and combinations of allistic and electrically propelled flight legs, we have investigated whether the set flight time limit could also be kept with a combination of solar-electric propulsion and a second, RTG-powered upper stage. The used ion engine type was the RIT-22 for the first stage and the RIT-10 for the second stage. Trajectory optimization was carried out with the low-thrust optimization program InTrance, which implements the method of Evolutionary Neurocontrol,using Artificial Neural Networks for spacecraft steering and Evolutionary Algorithms to optimize the Neural Networks’ parameter set. Based on a parameter space study, in which the number of thrust units, the unit’s specific impulse, and the relative size of the solar power generator were varied, we have chosen one configuration as reference. The transfer time of this reference configuration was 29.6 years and the fastest one, which is technically more challenging, still required 28.3 years. As all flight times of this parameter study were longer than 25 years, we further shortened the transfer time by applying a launcher-provided hyperbolic excess energy up to 49 km2/s2. The resulting minimal flight time for the reference configuration was then 27.8 years. The following, more precise optimization to a launch with the European Ariane 5 ECA rocket reduced the transfer time to 27.5 years. This is the fastest mission design of our study that is flexible enough to allow a launch every year. The inclusion of a fly-by at Jupiter finally resulted in a flight time of 23.8 years,which is below the set transfer-time limit. However, compared to the 27.5-year transfer,this mission design has a significantly reduced launch window and mission flexibility if the escape direction is restricted to the heliosphere’s “nose". KW - low-thrust trajectory optimization KW - heliosphere KW - ion propulsion Y1 - 2011 N1 - IEPC-2011-051 32nd International Electric Propulsion Conference,September 11–15, 2011 Wiesbaden, Germany SP - 1 EP - 12 ER - TY - CHAP A1 - Pirovano, Laura A1 - Seefeldt, Patric A1 - Dachwald, Bernd A1 - Noomen, Ron T1 - Attitude and Orbital Dynamics Modeling for an Uncontrolled Solar-Sail Experiment in Low-Earth Orbit T2 - 25th International Symposium on Spaceflight Dynamics, 2015, Munich, Germany Y1 - 2015 ER - TY - CHAP A1 - Frotscher, Ralf A1 - Goßmann, Matthias A1 - Temiz Artmann, Aysegül A1 - Staat, Manfred T1 - Simulation of cardiac cell-seeded membranes using the edge-based smoothed FEM T2 - 1st International Conference "Shell and Membrane Theories in Mechanics and Biology: From Macro- to Nanoscale Structures", Minsk, Belarus, Sept. 16-20, 2013 Y1 - 2013 SN - 978-985-553-135-8 SP - 165 EP - 167 PB - Verl. d. Weißruss. Staatl. Univ. CY - Minsk ER - TY - CHAP A1 - Jean-Pierre P., de Vera A1 - Baque, Mickael A1 - Billi, Daniela A1 - Böttger, Ute A1 - Bulat, Sergey A1 - Czupalla, Markus A1 - Dachwald, Bernd A1 - de la Torre, Rosa A1 - Elsaesser, Andreas A1 - Foucher, Frédéric A1 - Korsitzky, Hartmut A1 - Kozyrovska, Natalia A1 - Läufer, Andreas A1 - Moeller, Ralf A1 - Olsson-Francis, Karen A1 - Onofri, Silvano A1 - Sommer, Stefan A1 - Wagner, Dirk A1 - Westall, Frances T1 - The search for life on Mars and in the Solar System - strategies, logistics and infrastructures T2 - 69th International Astronautical Congress (IAC) N2 - The question "Are we alone in the Universe?" is perhaps the most fundamental one that affects mankind. How can we address the search for life in our Solar System? Mars, Enceladus and Europa are the focus of the search for life outside the terrestrial biosphere. While it is more likely to find remnants of life (fossils of extinct life) on Mars because of its past short time window of the surface habitability, it is probably more likely to find traces of extant life on the icy moons and ocean worlds of Jupiter and Saturn. Nevertheless, even on Mars there could still be a chance to find extant life in niches near to the surface or in just discovered subglacial lakes beneath the South Pole ice cap. Here, the different approaches for the detection of traces of life in the form of biosignatures including pre-biotic molecules will be presented. We will outline the required infrastructure for this enterprise and give examples of future mission concepts to investigate the presence of life on other planets and moons. Finally, we will provide suggestions on methods, techniques, operations and strategies for preparation and realization of future life detection missions. KW - life detection KW - Mars KW - icy moons KW - habitability KW - space missions Y1 - 2018 N1 - 69th International Astronautical Congress (IAC), Bremen, Germany, 1-5 October 2018. SP - 1 EP - 8 ER - TY - CHAP A1 - Dachwald, Bernd A1 - Kahle, Ralph A1 - Wie, Bong T1 - Solar sail Kinetic Energy Impactor (KEI) mission design tradeoffs for impacting and deflecting asteroid 99942 Apophis T2 - AIAA/AAS Astrodynamics Specialist Conference and Exhibit N2 - Near-Earth asteroid 99942 Apophis provides a typical example for the evolution of asteroid orbits that lead to Earth-impacts after a close Earth-encounter that results in a resonant return. Apophis will have a close Earth-encounter in 2029 with potential very close subsequent Earth-encounters (or even an impact) in 2036 or later, depending on whether it passes through one of several so-called gravitational keyholes during its 2029-encounter. Several pre-2029-deflection scenarios to prevent Apophis from doing this have been investigated so far. Because the keyholes are less than 1 km in size, a pre-2029 kinetic impact is clearly the best option because it requires only a small change in Apophis' orbit to nudge it out of a keyhole. A single solar sail Kinetic Energy Impactor (KEI) spacecraft that impacts Apophis from a retrograde trajectory with a very high relative velocity (75-80 km/s) during one of its perihelion passages at about 0.75 AU would be a feasible option to do this. The spacecraft consists of a 160 m x 160 m, 168 kg solar sail assembly and a 150 kg impactor. Although conventional spacecraft can also achieve the required minimum deflection of 1 km for this approx. 320 m-sized object from a prograde trajectory, our solar sail KEI concept also allows the deflection of larger objects. In this paper, we also show that, even after Apophis has flown through one of the gravitational keyholes in 2029, solar sail Kinetic Energy Impactor (KEI) spacecraft are still a feasible option to prevent Apophis from impacting the Earth, but many KEIs would be required for consecutive impacts to increase the total Earth-miss distance to a safe value. In this paper, we elaborate potential pre- and post-2029 KEI impact scenarios for a launch in 2020, and investigate tradeoffs between different mission parameters. KW - Solar Sail KW - Asteroid Deflection KW - Planetary Protection KW - Trajectory Optimization Y1 - 2006 U6 - https://doi.org/10.2514/6.2006-6178 N1 - AIAA/AAS Astrodynamics Specialist Conference and Exhibit, 21 August 2006 - 24 August 2006, Keystone, Colorado(USA). SP - 1 EP - 20 ER - TY - CHAP A1 - Baader, Fabian A1 - Keller, Denis A1 - Lehmann, Raphael A1 - Gerber, Lukas A1 - Reiswich, Martin A1 - Dachwald, Bernd A1 - Förstner, Roger T1 - Operating melting probes for ice penetration under sublimation conditions and in reduced gravity on a sounding rocket T2 - Proceedings of the 24th ESA Symposium on European Rocket and Balloon Programmes and related Research Y1 - 2019 SN - 0379-6566 N1 - 24th PAC Symposium 2019 ER - TY - CHAP A1 - Borggräfe, Andreas A1 - Dachwald, Bernd T1 - Mission performance evaluation for solar sails using a refined SRP force model with variable optical coefficients T2 - 2nd International Symposium on Solar Sailing N2 - Solar sails provide ignificant advantages over other low-thrust propulsion systems because they produce thrust by the momentum exchange from solar radiation pressure (SRP) and thus do not consume any propellant.The force exerted on a very thin sail foil basically depends on the light incidence angle. Several analytical SRP force models that describe the SRP force acting on the sail have been established since the 1970s. All the widely used models use constant optical force coefficients of the reflecting sail material. In 2006,MENGALI et al. proposed a refined SRP force model that takes into account the dependancy of the force coefficients on the light incident angle,the sail’s distance from the sun (and thus the sail emperature) and the surface roughness of the sail material [1]. In this paper, the refined SRP force model is compared to the previous ones in order to identify the potential impact of the new model on the predicted capabilities of solar sails in performing low-cost interplanetary space missions. All force models have been implemented within InTrance, a global low-thrust trajectory optimization software utilizing evolutionary neurocontrol [2]. Two interplanetary rendezvous missions, to Mercury and the near-Earth asteroid 1996FG3, are investigated. Two solar sail performances in terms of characteristic acceleration are examined for both scenarios, 0.2 mm/s2 and 0.5 mm/s2, termed “low” and “medium” sail performance. In case of the refined SRP model, three different values of surface roughness are chosen, h = 0 nm, 10 nm and 25 nm. The results show that the refined SRP force model yields shorter transfer times than the standard model. Y1 - 2010 N1 - 2nd International Symposium on Solar Sailing, ISSS 2010, 2010-07-20 - 2010-07-22. New York City College of Technology of the City University of New York, USA SP - 1 EP - 6 ER - TY - CHAP A1 - Tran, Ngoc Trinh A1 - Staat, Manfred T1 - FEM shakedown analysis of Kirchhoff-Love plates under uncertainty of strength T2 - Proceedings of UNCECOMP 2021 N2 - A new formulation to calculate the shakedown limit load of Kirchhoff plates under stochastic conditions of strength is developed. Direct structural reliability design by chance con-strained programming is based on the prescribed failure probabilities, which is an effective approach of stochastic programming if it can be formulated as an equivalent deterministic optimization problem. We restrict uncertainty to strength, the loading is still deterministic. A new formulation is derived in case of random strength with lognormal distribution. Upper bound and lower bound shakedown load factors are calculated simultaneously by a dual algorithm. Y1 - 2021 SN - 978-618-85072-6-5 U6 - https://doi.org/10.7712/120221.8041.19047 N1 - UNCECOMP 2021, 4th International Conference on Uncertainty Quantification in Computational Sciences and Engineering, streamed from Athens, Greece, 28–30 June 2021. SP - 323 EP - 338 ER - TY - CHAP A1 - Schoutetens, Frederic A1 - Dachwald, Bernd A1 - Heiligers, Jeannette T1 - Optimisation of photon-sail trajectories in the alpha-centauri system using evolutionary neurocontrol T2 - 8th ICATT 2021 N2 - With the increased interest for interstellar exploration after the discovery of exoplanets and the proposal by Breakthrough Starshot, this paper investigates the optimisation of photon-sail trajectories in Alpha Centauri. The prime objective is to find the optimal steering strategy for a photonic sail to get captured around one of the stars after a minimum-time transfer from Earth. By extending the idea of the Breakthrough Starshot project with a deceleration phase upon arrival, the mission’s scientific yield will be increased. As a secondary objective, transfer trajectories between the stars and orbit-raising manoeuvres to explore the habitable zones of the stars are investigated. All trajectories are optimised for minimum time of flight using the trajectory optimisation software InTrance. Depending on the sail technology, interstellar travel times of 77.6-18,790 years can be achieved, which presents an average improvement of 30% with respect to previous work. Still, significant technological development is required to reach and be captured in the Alpha-Centauri system in less than a century. Therefore, a fly-through mission arguably remains the only option for a first exploratory mission to Alpha Centauri, but the enticing results obtained in this work provide perspective for future long-residence missions to our closest neighbouring star system. Y1 - 2021 N1 - 8th ICATT (International Conference on Astrodynamics Tools and Techniques), 23 - 25 June 2021, Virtual SP - 1 EP - 15 ER - TY - CHAP A1 - Seefeldt, Patric A1 - Bauer, Waldemar A1 - Dachwald, Bernd A1 - Grundmann, Jan Thimo A1 - Straubel, Marco A1 - Sznajder, Maciej A1 - Tóth, Norbert A1 - Zander, Martin E. T1 - Large lightweight deployable structures for planetary defence: solar sail propulsion, solar concentrator payloads, large-scale photovoltaic power T2 - 4th IAA Planetary Defense Conference - PDC 2015, 13-17 April 2015, Frascati, Roma, Italy Y1 - 2015 N1 - IAA-PDC-15-P-20 ER -