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  - JOUR
A1  - Mikucki, Jill Ann
A1  - Schuler, C. G.
A1  - Digel, Ilya
A1  - Kowalski, Julia
A1  - Tuttle, M. J.
A1  - Chua, Michelle
A1  - Davis, R.
A1  - Purcell, Alicia
A1  - Ghosh, D.
A1  - Francke, G.
A1  - Feldmann, M.
A1  - Espe, C.
A1  - Heinen, Dirk
A1  - Dachwald, Bernd
A1  - Clemens, Joachim
A1  - Lyons, W. B.
A1  - Tulaczyk, S.
T1  - Field-Based planetary protection operations for melt probes: validation of clean access into the blood falls, antarctica, englacial ecosystem
JF  - Astrobiology
N2  - Subglacial environments on Earth offer important analogs to Ocean World targets in our solar system. These unique microbial ecosystems remain understudied due to the challenges of access through thick glacial ice (tens to hundreds of meters). Additionally, sub-ice collections must be conducted in a clean manner to ensure sample integrity for downstream microbiological and geochemical analyses. We describe the field-based cleaning of a melt probe that was used to collect brine samples from within a glacier conduit at Blood Falls, Antarctica, for geomicrobiological studies. We used a thermoelectric melting probe called the IceMole that was designed to be minimally invasive in that the logistical requirements in support of drilling operations were small and the probe could be cleaned, even in a remote field setting, so as to minimize potential contamination. In our study, the exterior bioburden on the IceMole was reduced to levels measured in most clean rooms, and below that of the ice surrounding our sampling target. Potential microbial contaminants were identified during the cleaning process; however, very few were detected in the final englacial sample collected with the IceMole and were present in extremely low abundances (∼0.063% of 16S rRNA gene amplicon sequences). This cleaning protocol can help minimize contamination when working in remote field locations, support microbiological sampling of terrestrial subglacial environments using melting probes, and help inform planetary protection challenges for Ocean World analog mission concepts.
Y1  - 2023
U6  - https://doi.org/10.1089/ast.2021.0102
SN  - 1557-8070 (online)
SN  - 153-1074 (print)
VL  - 23
IS  - 11
SP  - 1165
EP  - 1178
PB  - Liebert
CY  - New York, NY
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
ED  - Knopf, George K.
ED  - Otani, Yukitoshi
T1  - Light propulsion systems for spacecraft
T2  - Optical nano and micro actuator technology
Y1  - 2017
SN  - 9781315217628 (eBook)
SP  - 577
EP  - 598
PB  - CRC Press
CY  - Boca Raton
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
A1  - Wurm, P.
T1  - Mission analysis for an advanced solar photon thruster
T2  - 60th International Astronautical Congress 2009, IAC 2009
N2  - The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), is a solar sail design concept, for which the two basic functions of the solar sail, namely light collection and thrust direction, are uncoupled. In this paper, we introduce a novel SPT concept, termed the Advanced Solar Photon Thruster (ASPT). This model does not suffer from the simplified assumptions that have been made for the analysis of compound solar sails in previous studies. We present the equations that describe the force, which acts on the ASPT. After a detailed design analysis, the performance of the ASPT with respect to the conventional flat solar sail (FSS) is investigated for three interplanetary mission scenarios: An Earth-Venus rendezvous, where the solar sail has to spiral towards the Sun, an Earth-Mars rendezvous, where the solar sail has to spiral away from the Sun, and an Earth-NEA rendezvous (to near-Earth asteroid 1996FG3), where a large orbital eccentricity change is required. The investigated solar sails have realistic near-term characteristic accelerations between 0.1 and 0.2mm/s2. Our results show that a SPT is not superior to the flat solar sail unless very idealistic assumptions are made.
KW  - Interplanetary flight
Y1  - 2009
SN  - 978-161567908-9
N1  - 60th International Astronautical Congress 2009, IAC 2009; Daejeon; South Korea; 12 October 2009 through 16 October 2009
VL  - 8
SP  - 6838
EP  - 6851
PB  - Elsevier
CY  - Amsterdam
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  -