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70th International Astronautical Congress, IAC 2019

作者： Browder, Becca Newman, Dava Department of Aeronautics and Astronautics Technology and Policy Program Massachusetts Insitute of Technology United States

policymakers around the world-from Hawaii and Georgia to Scotland and Portugal-are weighing whether to build their own commercial spaceports. A spaceport requires significant investment of public funds, which can be risky considering there is already an overcapacity of launch sites in comparison to launch demand. To study this issue, a literature review and financial analysis of U.S. spaceports was performed to understand how spaceports are constructed and operated, and whether a commercial spaceport is a feasible and sustainable business prospect. This paper summarizes a literature review and creates a methodology for performing a financial analysis of a commercial spaceport by using the Virginia Commercial Space Flight Authority (VCSFA) as a test case. The financial analysis of VCSFA showed that the spaceport in question relies on public funding to remain profitable, which may not be surprising given that a spaceport at its core an infrastructure investment. This work shows that calling a spaceport "commercial" is a bit of a misnomer because these "commercial" spaceports are typically run by state agencies that receive significant public investment. In addition, the analysis shows that the VCSFA is still in the startup phase, characterized by operating losses, so it is too soon to tell whether this spaceport can be a feasible and sustainable business. This initial financial analysis shows that investing in a spaceport is a long-term commitment that may not have direct financial returns on investment but may have corollary benefits. While the commercial space industry is growing significantly, it remains to be seen whether launch demand will change significantly to justify the construction of additional spaceports when there is already an overcapacity of launch sites. Copyright © 2019 by the International Astronautical Federation (IAF). All rights reserved.

关键词： Investments

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Autonomously deployable tower infrastructure for exploration and communication in lunar permanently shadowed regions

Autonomously deployable tower infrastructure for exploration...

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Accelerating Space Commerce, Exploration, and New Discovery Conference, ASCEND 2020

作者： Amy, Caleb Bégin, Marc-André Browder, Becca Chan, Manwei Dawson, Charles Pereira, Paula Do Vale Hank, Travis J. Hinterman, Eric Lordos, George Martell, Benjamin Miller, Alex O’neill, Cormac Padia, Vineet J. Stamler, Natasha Todd, Jessica Wang, Nieky Newman, Dava J. de Weck, Olivier L. Hoffman, Jeffrey A. Dept of Mechanical Engineering Massachusetts Institute of Technology CambridgeMA02139 United States Dept of Aeronautics and Astronautics and Technology & Policy Program Massachusetts Institute of Technology CambridgeMA02139 United States Dept of Aeronautics and Astronautics Massachusetts Institute of Technology CambridgeMA02139 United States Physics and EECS Massachusetts Institute of Technology CambridgeMA02139 United States Dept of Mechanical Engineering Massachusetts Institute of Technology CambridgeMA02139 United States Mechanical Engineering and Urban Planning Massachusetts Institute of Technology CambridgeMA02139 United States Dept of Aeronautics and Astronautics Woods Hole Oceanographic Institute Massachusetts Institute of Technology CambridgeMA02139 United States Massachusetts Institute of Technology CambridgeMA02139 United States Aeronautics and Astronautics and Engineering Systems Dept of Aeronautics and Astronautics Massachusetts Institute of Technology CambridgeMA02139 United States

ISBN: (纸本)9781624106088

NASA is interested in characterising and robotically exploring the lunar permanently shadowed regions (PSRs) in advance of Artemis crewed landings. The challenging terrain of these regions means a lander would only be able to access the rim of a PSR, limiting line-of-sight communication and sensing into the PSR. Autonomously deployed lunar tower infrastructures could provide valuable lines of sight into and around these PSRs. NASA has developed deployable composite booms for use in microgravity, and we propose an extension of those capabilities by deploying a composite boom vertically in the lunar gravity field. Services hosted by the elevated platform at the top of the boom, such as power beaming, radio repeaters, or imagers, could support the near-term operations of multiple distributed, mobile, robotic assets as well as long-term regional operations of exploration crews. The Multifunctional Expandable Lunar Lightweight, Tall Tower (MELLTT) design, created by our interdisciplinary team of MIT graduate and undergraduate students in October 2019, has been selected and funded by NASA STMD and Space Grant as a finalist in the National Institute of Aerospace’s NASA BIG Idea 2020 Challenge and will be demonstrated at the virtual BIG Idea Forum in January 2021. The expected result of this work is a proof-of-concept of a TRL 4 prototype of a deployable, tall lunar tower by January 2021, setting the stage for future development along a path to flight targeting an early 2020’s lunar tower technology demonstration mission in support of the Artemis program. © 2020 The MITRE Corporation. All Rights Reserved.

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Graphene Aerogel-Enhanced DBD Reactor with Thermoelectric Energy Recovery for Superior Plasma Activated Water Production

Graphene Aerogel-Enhanced DBD Reactor with Thermoelectric En...

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2024 International Conference on Applied Sciences and Material Applications, ICASMA 2024

作者： Seetawan, Chatchavit Namhongsa, Wanatchaporn Ruamruk, Surasak Thaowankaew, Somporn Min, Zhu Chaohai, Zhang Seetawan, Tosawat Plasma Research Laboratory Center of Excellence on Alternative Energy Research and Development Institution Sakon Nakhon Rajabhat University 680 Nittayo Road Mueang District Sakhon Nakhon470001 Thailand Thermoelectric Research Laboratory Center of Excellence on Alternative Energy Research and Development Institution Sakon Nakhon Rajabhat University 680 Nittayo Road Mueang District Sakhon Nakhon470002 Thailand Policy and Planning Division Office of the President Sakon Nakhon Rajabhat University 680 Nittayo Road Mueang District Sakhon Nakhon470003 Thailand Nanjing University of Aeronautics and Astronautics 29 Yudao Street Jiangsu Province China4 Nanjing210016 China Program of Physics Faculty of Science and Technology Sakon Nakhon Rajabhat University 680 Nittayo Road Mueang District Sakhon Nakhon470005 Thailand

This study investigates plasma-activated water (PAW) production enhancement using a Dielectric Barrier Discharge (DBD) reactor integrated with graphene aerogel inserts. It explores the potential for thermoelectric energy recovery. The research focuses on optimizing PAW generation by leveraging graphene aerogel’s high surface area and porosity to improve plasma-water interaction and increase the dissolution of reactive oxygen and nitrogen species (RONS). Additionally, the study examines the integration of thermoelectric materials within the reactor system to recover and utilize the thermal energy generated during plasma activation. A rotating DBD reactor design facilitates dynamic mixing and enhances contact between plasma and water. Key parameters are systematically evaluated, including rotation speed, aerogel characteristics, discharge conditions, and thermoelectric material performance. Results indicate that graphene aerogel significantly boosts PAW production efficiency while including thermoelectric materials, contributing to energy recovery and making the process more sustainable. This dual advancement in PAW technology offers potential applications in biomedical treatments, environmental remediation, and energy-efficient industrial processes. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Dielectric barrier discharge

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Decarbonization of aviation via hydrogen propulsion: technology performance targets and energy system impacts

arXiv

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arXiv 2023年

作者： Cybulsky, Anna Allroggen, Florian Shao-Horn, Yang Mallapragada, Dharik S. MIT Energy Initiative Massachusetts Institute of Technology CambridgeMA02139 United States Laboratory for Aviation and the Environment Department of Aeronautics and Astronautics Massachusetts Institute of Technology CambridgeMA02139 United States Joint Program on the Science Policy of Global Change Massachusetts Institute of Technology CambridgeMA02139 United States Research Laboratory of Electronics Massachusetts Institute of Technology CambridgeMA02139 United States Department of Materials Science and Engineering Massachusetts Institute of Technology CambridgeMA02139 United States Department of Mechanical Engineering Massachusetts Institute of Technology CambridgeMA02139 United States

The aviation sector is challenging to decarbonize since aircraft require high power and energy per unit of weight. Liquid hydrogen is an interesting solution due to its high gravimetric energy density, minimal warming impact, and low-carbon production potential. We quantify the performance targets for fuel cell systems and on-board storage to enable hydrogen-powered regional aviation. We then explore the energy infrastructure impacts of meeting this additional H2 demand in the European context under deep decarbonization scenarios. We find that minimal payload reduction would be needed for powering regional aviation up to 1000 nmi if fuel cell system specific power of 2 kW/kg and tank gravimetric index of 50% can be achieved. The energy systems analysis highlights the importance of utilizing multiple technology options: such as nuclear expansion and natural gas reforming with CCS for hydrogen production. Levelized cost of liquid hydrogen as low as €3.5/kg demonstrates pathways for Europe to achieve cost-competitive production. Copyright © 2023, The Authors. All rights reserved.

关键词： Hydrogen storage

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Correction: Impacts of a near-future supersonic aircraft fleet on atmospheric composition and climate

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Environmental Science: Atmospheres 2022年第3期2卷 547-547页

作者： Sebastian D. Eastham Thibaud Fritz Inés Sanz-Morère Prakash Prashanth Florian Allroggen Ronald G. Prinn Raymond L. Speth Steven R. H. Barrett Laboratory for Aviation and the Environment Department of Aeronautics and Astronautics Massachusetts Institute of Technology Cambridge MA 02139 USA seastham@mit.edu Joint Program for the Science and Policy of Global Change Massachusetts Institute of Technology Cambridge MA 02139 USA Department of Earth Atmospheric and Planetary Sciences Massachusetts Institute of Technology USA

Correction for ‘Impacts of a near-future supersonic aircraft fleet on atmospheric composition and climate’ by Sebastian D. Eastham et al. , Environ. Sci.: Atmos. , 2022, https://***/10.1039/D1EA00081K .

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Large satellite constellation orbital debris impacts: Case studies of oneweb and SpaceX proposals

Large satellite constellation orbital debris impacts: Case s...

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AIAA Space and astronautics Forum and Exposition, SPACE 2017

作者： Foreman, Veronica L. Siddiqi, Afreen de Weck, Olivier L. Massachusetts Institute of Technology Department of Aeronautics & Astronautics and Technology and Policy Program Building 33-409 CambridgeMA02139 United States Massachusetts Institute of Technology Institute for Data Systems and Society MIT Building 33- 410 CambridgeMA02139 United States Massachusetts Institute of Technology Department of Aeronautics & Astronautics MIT Building 33- 410 CambridgeMA02139 United States

ISBN: (数字)9781624104831

ISBN: (纸本)9781624104831

Recent proposals for large constellations of communications satellites have added to the debate surrounding the long-term impact of large satellite constellations on spectrum regulation and orbital debris propagation. The many spectrum license applications currently before the Federal Communications Commission for large, non-geostationary satellite constellation systems provide the satellite risk community with a unique opportunity to weigh the promise of these missions against their long-term impact on the orbital debris environment prior to their launch. The last decade has seen approximately a 60% increase in the total orbital debris object count, and the additional impact of these pending proposals could significantly alter the LEO environment. Furthermore, regulators should examine these proposals within the existing space policy framework to identify potential regulatory inefficiencies. Much of the existing literature focuses on the risk that the orbital environment poses to satellite constellations and distributed spacecraft missions, but the pending constellation requests can serve as case studies for examining the risk that large satellite constellations pose to the orbital environment. Better understanding the proposed systems will offer insight into the risks that mission managers and regulators may be accepting now on behalf the future space community. By examining the licensed OneWeb broadband services satellite constellation and the proposed initial deployment of a similar SpaceX system using the NASA Johnson Space Center Orbital Debris Engineering Model software (Version 3) and a small Monte Carlo analysis, we are able to examine potential implications of the proposed missions, as well as the policy decision space that may emerge as these proposals are reviewed over the coming months and years. © 2017, American Institute of aeronautics and astronautics Inc, AIAA. All rights reserved.

关键词： NASA

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Using space-inspired education tools to enhance STEM learning in rural communities

Using space-inspired education tools to enhance STEM learnin...

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作者： Anderson, Allison Trotti, Guillermo Luis Wilcox, Suzanne Marie Gundersen, Elizabeth Perry Newman, Dava J. Department of Aeronautics and Astronautics and the Technology Policy Program Massachusetts Institute of Technology United States Trotti and Asssociates Inc. United States ExplorationWorks Museum of Science and Culture Helena MT United States

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RFID-based automated Asset Management for the international Space Station: RAMSES prototype test results and implications for ISS and constellation

RFID-based automated Asset Management for the international ...

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作者： Grindle, Abraham T. De Weck, Olivier L. Parrish, Joseph C. Massachusetts Institute of Technology Cambridge MA 02139 United States Aurora Flight Sciences Corporation Cambridge MA 02142 United States Department of Aeronautics and Astronautics Technology nad Policy Program Building 33-410 77 Massachusetts Ave. Cambridge MA 02139 United States Department of Aeronautics and Astronautics Engineering Systems Division Building E40-261 United States Research and Development One Broadway 12th Floor Cambridge MA 02139 United States

ISBN: (纸本)9781563479793

The performance of a prototype RFID-wired NASA Cargo Transfer Bag (CTB), implementing the Rule-based analytic Asset Management for Space Exploration Systems (RAMSES) architecture, was recently tested in both standard and reduced gravity conditions. In addition to gravity, other experimental variables included the material of the test articles (paper, metal, or liquid) and the number of articles within the container at one time. As predicted by ground test results, the best read rates were observed during reduced-gravity flight, with metals detected at 100% accuracy, paper at 96%, and water at roughly 93%, when tests were conducted with 30 articles of the material in the "smart CTB". These results, while still at the prototype level, demonstrate that the system holds significant potential for future flight implementation on ISS and future human spaceflight outposts. Copyright © 2009 by Abraham T. Grindle.

关键词： Asset management

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Preliminary analysis of strategies and challenges to encourage data link adoption over the North Atlantic airspace

Preliminary analysis of strategies and challenges to encoura...

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作者： Campos, Norma V. Weigel, Annalisa L. Hansman, R. John Massachusetts Institute of Technology Technology and Policy Program Engineering Systems Division United States Massachusetts Institute of Technology Department of Aeronautics and Astronautics and of Engineering Systems United States Massachusetts Institute of Technology Department of Aeronautics and Astronautics United States

A survey of commercial operators and Air Navigation Service Providers in the North Atlantic (NAT) was conducted with the objective of identifying potential strategies for increasing efficiency of operations and promoting the adoption of data link communications. Stakeholders identified fuel penalties associated with the inability to fly preferred routes and levels as the main operational inefficiency in the NAT. Data link is perceived as the enabler to improve operations through applications such as reducing separation minima. Although operational benefits from data link have been significant, economic benefits have not been achieved yet, as major applications have not been implemented. Initial costs of infrastructure and equipment as well as uncertainty in the establishment and harmonization of procedures and technologies are some of the main barriers to data link equipage. However, delivering value from data link to all stakeholders is more than balancing costs and benefits. A number of issues regarding policies, procedures, safety, and technical aspects need to be resolved first. A combination of operational, financial, and regulatory strategies may be necessary to encourage data link adoption. Copyright © 2008 by Norma V. Campos.

关键词： Air navigation

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An autonomous, real-time asset management system for the International Space Station: Net present value analysis

An autonomous, real-time asset management system for the Int...

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Space 2008 Conference

作者： Grindle, Abraham T. De Weck, Olivier L. Shull, Sarah A. Department of Aeronautics and Astronautics and Technology and Policy Program Massachusetts Institute of Technology Building 33-412 Cambridge MA 02139 United States Department of Aeronautics and Astronautics and Engineering Systems Division Massachusetts Institute of Technology Building 33-412 Cambridge MA 02139 United States DO5/Cargo Integration and Operations Branch NASA Lyndon B. Johnson Space Center Mission Operations Directorate Houston TX 77058 United States

ISBN: (纸本)9781563479465

This paper provides a cost-benefit analysis for a real-time, autonomous inventory management system for the International Space Station (ISS) based upon Radio Frequency Identification (RFID) technology. This paper describes a Net Present Value (NPV) analysis of a possible application of the system to the International Space Station's cargo transfer bags. Quantities such as crew time, cargo launch volume, and cargo launch mass were monetized to allow comparison of costs and benefits, and several different implementation scenarios were evaluated. The analysis found that the application has marginal or negative value under conservative assumptions, but possibly significant positive value when inventory transactions are concentrated in a subset of the total cargo transfer bag population, and/or if ISS Operations are continued into 2018/2020. We show that a modest concentration of inventory transactions - for example, 75% of transactions occurring in the 50% of the bags that are RFID equipped - results in a positive mean NPV of approximately $46.8 million, and an 84% probability of a positive NPV. Also, a gradual Phase-In Implementation Scenario - as it is modeled in this work - is inferior to a more rapid deployment of the system via Modification Kits. Copyright © 2008 by Abraham T. Grindle.

关键词： Cost benefit analysis

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