Here Is an Ambitious and Vigorous Space Program Leading to Eventual Space Settlement
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Appendix 1 Some Astrophysical Reminders
Appendix 1 Some Astrophysical Reminders Marc Ollivier 1.1 A Physics and Astrophysics Overview 1.1.1 Star or Planet? Roughly speaking, we can say that the physics of stars and planets is mainly governed by their mass and thus by two effects: 1. Gravitation that tends to compress the object, thus releasing gravitational energy 2. Nuclear processes that start as the core temperature of the object increases The mass is thus a good parameter for classifying the different astrophysical objects, the adapted mass unit being the solar mass (written Ma). As the mass decreases, three categories of objects can be distinguished: ∼ 1. if M>0.08 Ma ( 80MJ where MJ is the Jupiter mass) the mass is sufficient and, as a consequence, the gravitational contraction in the core of the object is strong enough to start hydrogen fusion reactions. The object is then called a “star” and its radius is proportional to its mass. 2. If 0.013 Ma <M<0.08 Ma (13 MJ <M<80 MJ), the core temperature is not high enough for hydrogen fusion reactions, but does allow deuterium fu- sion reactions. The object is called a “brown dwarf” and its radius is inversely proportional to the cube root of its mass. 3. If M<0.013 Ma (M<13 MJ) the temperature a the center of the object does not permit any nuclear fusion reactions. The object is called a “planet”. In this category one distinguishes giant gaseous and telluric planets. This latter is not massive enough to accrete gas. The mass limit between giant and telluric planets is about 10 terrestrial masses. -
"High Accuracy Rotation--Vibration Calculations on Small Molecules" In
High Accuracy Rotation–Vibration Calculations on Small Molecules Jonathan Tennyson Department of Physics and Astronomy, University College London, London, UK 1 INTRODUCTION comprehensive understanding requires the knowledge of many millions, perhaps even billions, of individual transi- High-resolution spectroscopy measures the transitions bet- tions (Tennyson et al. 2007). It is not practical to measure ween energy levels with high accuracy; typically, uncer- this much data in the laboratory and therefore a more real- tainties are in the region of 1 part in 108. Although it is istic approach is the development of an accurate theoretical possible, under favorable circumstances, to obtain this sort model, benchmarked against experiment. of accuracy by fitting effective Hamiltonians to observed The incompleteness of most experimental datasets means spectra (see Bauder 2011: Fundamentals of Rotational that calculations are useful for computing other properties Spectroscopy, this handbook), such ultrahigh accuracy is that can be associated with spectra. The partition functions largely beyond the capabilities of purely ab initio proce- and the variety of thermodynamic properties that are linked dures. Given this, it is appropriate to address the question to this (Martin et al. 1991) are notable among these. Again, of why it is useful to calculate the spectra of molecules ab calculations are particularly useful for estimating these initio (Tennyson 1992). quantities at high temperature (e.g., Neale and Tennyson The concept of the potential energy surfaces, which in 1995). turn is based on the Born–Oppenheimer approximation, Other more fundamental reasons for calculating spectra underpins nearly all of gas-phase chemical physics. The include the search for unusual features, such as clustering of original motivation for calculating spectra was to provide energy levels (Jensen 2000) or quantum monodromy (Child stringent tests of potential energy surfaces. -
Moriba Kemessia Jah, Ph.D. August 2020 THE
Moriba Kemessia Jah, Ph.D. August 2020 THE UNIVERSITY OF TEXAS AT AUSTIN Cockrell School of Engineering Resume FULL NAME: Moriba Kemessia Jah TITLE: Associate Professor DEPARTMENT: Aerospace Engineering and Engineering Mechanics EDUCATION: Embry-Riddle Aeronautical University Aerospace Engineering B.S. 1999 University of Colorado (Boulder) Aerospace Engineering Sci M.S. 2001 University of Colorado (Boulder) Aerospace Engineering Sci Ph.D. 2005 PROFESSIONAL REGISTRATION: Not Registered CURRENT AND PREVIOUS ACADEMIC POSITIONS: Associate Professor (with Tenure), The University of Texas at Austin, • Department of Aerospace Engineering and Engineering Mechanics, February 2020 – present Affiliate Faculty, The University of Texas at Austin • Environmental Sciences Institute, October 2019 – present Visiting Professor, Australian National University • Research School of Aerospace, Mechanical, and Environmental Engineering (RSAMEE), July 2019 – present Core Faculty, The University of Texas at Austin, • Oden Institute for Computational Engineering and Sciences, August 2018 – present Director, The University of Texas at Austin, • Oden Institute Computational Astronautical Sciences and Technologies Group, August 2018 - present Associate Professor (Tenure-Track), The University of Texas at Austin, • Department of Aerospace Engineering and Engineering Mechanics, April 2017 – February 2020 • Statistics and Data Science Department (Courtesy), October 2017 – present Program Lead and Distinguished Scholar, The University of Texas at Austin, • Robert Strauss -
The Rotational Spectrum of Protonated Sulfur Dioxide, HOSO+
A&A 533, L11 (2011) Astronomy DOI: 10.1051/0004-6361/201117753 & c ESO 2011 Astrophysics Letter to the Editor The rotational spectrum of protonated sulfur dioxide, HOSO+ V. Lattanzi1,2, C. A. Gottlieb1,2, P. Thaddeus1,2, S. Thorwirth3, and M. C. McCarthy1,2 1 Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138, USA e-mail: [email protected] 2 School of Engineering & Applied Sciences, Harvard University, 29 Oxford St., Cambridge, MA 02138, USA 3 I. Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany Received 21 July 2011 / Accepted 19 August 2011 ABSTRACT Aims. We report on the millimeter-wave rotational spectrum of protonated sulfur dioxide, HOSO+. Methods. Ten rotational transitions between 186 and 347 GHz have been measured to high accuracy in a negative glow discharge. Results. The present measurements improve the accuracy of the previously reported centimeter-wave spectrum by two orders of magnitude, allowing a frequency calculation of the principal transitions to about 4 km s−1 in equivalent radial velocity near 650 GHz, or one linewidth in hot cores and corinos. Conclusions. Owing to the high abundance of sulfur-bearing molecules in many galactic molecular sources, the HOSO+ ion is an excellent candidate for detection, especially in hot cores and corinos in which SO2 and several positive ions are prominent. Key words. ISM: molecules – radio lines: ISM – molecular processes – molecular data – line: identification 1. Introduction abundant in hot regions; (6) and radio observations of SH+ and SO+ (Menten et al. 2011; Turner 1994) have established that pos- Molecules with sulfur account for about 10% of the species iden- itive ions of sulfur-bearing molecules are surprisingly abundant tified in the interstellar gas and circumstellar envelopes. -
ASTRIA Ontology: Open, Standards-Based, Data-Aggregated Representation of Space Objects
Space Traffic Management Conference 2019 Progress through Collaboration Feb 26th, 2:00 PM ASTRIA Ontology: Open, Standards-based, Data-aggregated Representation of Space Objects Jennie Wolfgang The University of Texas at Austin, [email protected] Kathleen Krysher The University of Texas at Austin, [email protected] Michael Slovenski The University of Texas at Austin, [email protected] Unmil P. Karadkar The University of Texas at Austin, [email protected] Shiva Iyer The University of Texas at Austin, [email protected] See next page for additional authors Follow this and additional works at: https://commons.erau.edu/stm Part of the Cataloging and Metadata Commons, Databases and Information Systems Commons, and the Space Vehicles Commons Wolfgang, Jennie; Krysher, Kathleen; Slovenski, Michael; Karadkar, Unmil P.; Iyer, Shiva; and Jah, Moriba K., "ASTRIA Ontology: Open, Standards-based, Data-aggregated Representation of Space Objects" (2019). Space Traffic Management Conference. 2. https://commons.erau.edu/stm/2019/presentations/2 This Event is brought to you for free and open access by the Conferences at Scholarly Commons. It has been accepted for inclusion in Space Traffic Management Conference by an authorized administrator of Scholarly Commons. For more information, please contact [email protected]. Presenter Information Jennie Wolfgang, Kathleen Krysher, Michael Slovenski, Unmil P. Karadkar, Shiva Iyer, and Moriba K. Jah This event is available at Scholarly Commons: https://commons.erau.edu/stm/2019/presentations/2 -
IAA Situation Report on Space Debris - 2016
IAA Situation Report on Space Debris - 2016 Editors: Christophe Bonnal Darren S. McKnight International A cadem y of A stronautics Notice: The cosmic study or position paper that is the subject of this report was approved by the Board of Trustees of the International Academy of Astronautics (IAA). Any opinions, findings, conclusions, or recommendations expressed in this report are those of the authors and do not necessarily reflect the views of the sponsoring or funding organizations. For more information about the International Academy of Astronautics, visit the IAA home page at www.iaaweb.org. Copyright 2017 by the International Academy of Astronautics. All rights reserved. The International Academy of Astronautics (IAA), an independent nongovernmental organization recognized by the United Nations, was founded in 1960. The purposes of the IAA are to foster the development of astronautics for peaceful purposes, to recognize individuals who have distinguished themselves in areas related to astronautics, and to provide a program through which the membership can contribute to international endeavours and cooperation in the advancement of aerospace activities. © International Academy of Astronautics (IAA) May 2017. This publication is protected by copyright. The information it contains cannot be reproduced without written authorization. Title: IAA Situation Report on Space Debris - 2016 Editors: Christophe Bonnal, Darren S. McKnight Printing of this Study was sponsored by CNES International Academy of Astronautics 6 rue Galilée, Po Box 1268-16, 75766 Paris Cedex 16, France www.iaaweb.org ISBN/EAN IAA : 978-2-917761-56-4 Cover Illustration: NASA IAA Situation Report on Space Debris - 2016 Editors Christophe Bonnal Darren S. -
Allocation of Commercial Space Industry Components 1
May 2018 Allocation of Commercial S pace Industry Components A Virtual Think Tank (ViTTa)® Report Deeper Analyses Clarifying Insights Better Decisions Produced in support of the Strategic Multilayer Assessment (SMA) Office (Joint Staff, J39) www.NSIteam.com Allocation of Commercial Space Industry Components 1 Authors Dr. Belinda Bragg Dr. Sabrina Pagano Please direct inquiries to Belinda Bragg at [email protected] ViTTa® Project Team Dr. Allison Astorino-Courtois Sarah Canna Nicole Peterson Executive VP Principal Analyst Analyst Weston Aviles Dr. Larry Kuznar George Popp Analyst Chief Cultural Sciences Officer Senior Analyst Dr. Belinda Bragg Dr. Sabrina Pagano Dr. John A. Stevenson Principal Research Scientist Principal Research Scientist Principal Research Scientist Interview Team1 Weston Aviles Nicole Peterson Analyst Analyst Sarah Canna George Popp Principal Analyst Senior Analyst What is ViTTa®? NSI’s Virtual Think Tank (ViTTa®) provides rapid response to critical information needs by pulsing our global network of subject matter experts (SMEs) to generate a wide range of expert insight. For this SMA Contested Space Operations project, ViTTa was used to address 23 unclassified questions submitted by the Joint Staff and US Air Force project sponsors. The ViTTa team received written and verbal input from over 111 experts from National Security Space, as well as civil, commercial, legal, think tank, and academic communities working space and space policy. Each Space ViTTa report contains two sections: 1) a summary response to the question asked; and 2) the full written and/or transcribed interview input received from each expert contributor organized alphabetically. Biographies for all expert contributors have been collated in a companion document. -
Orbit Estimation of Geosynchronous Objects Via Ground-Based and Space-Based Optical Tracking
Orbit Estimation of Geosynchronous Objects Via Ground-Based and Space-Based Optical Tracking by Jill Tombasco B.S., Pennsylvania State University, 2005 M.S., University of Colorado, 2009 A thesis submitted to the Faculty of the Graduate School of the University of Colorado in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Aerospace Engineering Sciences 2011 This thesis entitled: Orbit Estimation of Geosynchronous Objects Via Ground-Based and Space-Based Optical Tracking written by Jill Tombasco has been approved for the Department of Aerospace Engineering Sciences Dr. Penina Axelrad Dr. George Born Date The final copy of this thesis has been examined by the signatories, and we find that both the content and the form meet acceptable presentation standards of scholarly work in the above mentioned discipline. iii Tombasco, Jill (Ph.D., Aerospace Engineering Sciences) Orbit Estimation of Geosynchronous Objects Via Ground-Based and Space-Based Optical Tracking Thesis directed by Dr. Penina Axelrad Angles-only orbit estimation of geosynchronous objects is a unique challenge due to the dense population of clustered geosynchronous objects, the singularities of and perturbations to geosynchronous motion, and the error inherent to experimental observations of geosynchronous objects. Passive optical tracking of geosynchronous space objects has traditionally been performed by ground-based sensors, and the capability has advanced significantly through the introduction of space-based angles-only tracking. This research addresses three key facets of geosynchronous orbit estimation accuracy: improvement to the accuracy via appropriate coordinate modeling, empirical characterization of achievable ground-based angles-only estimation accuracy, and analytic mod- eling of the space-based angles-only estimated uncertainty. -
Water on the Sun: the Sun Yields More Secrets to Spectroscopy
Contemporary Physics, 1998, volume 39, number 4, pages 283 ± 294 Water on the Sun: the Sun yields more secrets to spectroscopy JONATHAN TENNYSON and OLEG L. POLYANSKY Analysis of sunlight, which started the discipline of spectroscopy, has been the key to a number of major scienti® c discoveries. Sunspots, which are much cooler than most of the Sun’s surface, have particularly rich and complicated spectra which has long been thought to be due to very hot water. The challenge of analysing this spectrum has stimulated the development of new theoretical procedures based on full quantum mechanical treatments of the vibrational and rotational motion of the water molecule. The result has been the identi® cation of novel spectral features and a deeper understanding of how excited molecules such as superheated water behave. This work has applications ranging from the models of cool star atmospheres and rocket exhausts to the possible automated detection of forest ® res. Perhaps the most interesting result is the insight given to understanding how our own atmosphere absorbs sunlight, and the possible consequences that this may have for modelling the greenhouse eŒect. 1. Spectroscopy and the Sun Sun’s photosphere. The remaining absorptions are caused In 1814 Fraunhofer allowed a beam of sunlight from a by molecules such as water and oxygen in the Earth’s narrow opening in his shutters to pass through a prism and atmosphere which also absorb sunlight. Such spectral to be projected onto a white wall. What Fraunhofer saw analysis of light, possible both at visible and non-visible was not only the colours of the rainbow, which had been wavelengths, yields the vast majority of our knowledge not observed in this manner since Newton, but also `almost only about the rest of the Universe but also about the countless strong and weak vertical lines’ [1], see ® gure 1. -
A Diatomic Molecule Is One Atom Too Few the Successful Laser Cooling of a Triatomic Molecule Paves the Way Towards the Study of Ultracold Polyatomic Molecules
VIEWPOINT A Diatomic Molecule is One Atom too Few The successful laser cooling of a triatomic molecule paves the way towards the study of ultracold polyatomic molecules. by Paul Hamilton∗ and Eric R. Hudsony hysicists considering a foray into the study of molecules are often warned that “a diatomic molecule is one atom too many!” [1]. Now John Doyle and colleagues [2] at Harvard University have Pthrown this caution to the wind and tackled laser cooling of a triatomic molecule with success, opening the door to the study of ultracold polyatomic molecules. The technique of laser cooling [3], which uses the scat- tering of laser photons and the concomitant momentum transfer to bring atoms to a near halt, has revolutionized atomic, molecular, and optical (AMO) physics. Laser cooling and an important variant known as Sisyphus cooling [4] un- derpin three Nobel prizes in physics—for magneto-optical trapping (1997), Bose-Einstein condensation (2001), and the manipulation of individual quantum systems (2012)—and are crucial to a host of quantum-assisted technologies and fundamental physics measurements. Since photons carry very little momentum and therefore reduce an atom’s velocity by just a small amount, a pre- requisite for effective laser cooling is the ability to scatter thousands of photons. Thus laser cooling has predominantly been used only to cool simple atoms, whose electronic struc- ture dictates that after a photon is absorbed, spontaneous Figure 1: Doyle and colleagues [2] have cooled SrOH molecules emission places the atomic electron back into its original using Sisyphus cooling. In this type of cooling, the SrOH state, allowing the process to repeat nearly ad infinitum. -
Rotational Hybridization, and Control of Alignment and Orientation in Triatomic Ultralong-Range Rydberg Molecules
Home Search Collections Journals About Contact us My IOPscience Rotational hybridization, and control of alignment and orientation in triatomic ultralong-range Rydberg molecules This content has been downloaded from IOPscience. Please scroll down to see the full text. 2015 New J. Phys. 17 013021 (http://iopscience.iop.org/1367-2630/17/1/013021) View the table of contents for this issue, or go to the journal homepage for more Download details: IP Address: 138.5.159.110 This content was downloaded on 14/03/2015 at 01:03 Please note that terms and conditions apply. New J. Phys. 17 (2015) 013021 doi:10.1088/1367-2630/17/1/013021 PAPER Rotational hybridization, and control of alignment and orientation in OPEN ACCESS triatomic ultralong-range Rydberg molecules RECEIVED 24 June 2014 Rosario González-Férez1,2, H R Sadeghpour3 and Peter Schmelcher2,4 ACCEPTED FOR PUBLICATION 1 Instituto Carlos I de Física Teórica y Computacional, and Departamento de Física Atómica, Molecular y Nuclear, Universidad de 3 December 2014 Granada, E-18071 Granada, Spain PUBLISHED 2 The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, D-22761 Hamburg, Germany 15 January 2015 3 ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138, USA 4 Zentrum für Optische Quantentechnologien, Universität Hamburg, Luruper Chaussee 149, D-22761 Hamburg, Germany Content from this work may be used under the E-mail: [email protected] terms of the Creative Commons Attribution 3.0 Keywords: Rydberg molecules, electric field, control of alignment and orientation, ultralong-range licence. Any further distribution of this work must maintain attribution to the author Abstract (s) and the title of the work, journal citation and We explore the electronic structure and rovibrational properties of an ultralong-range triatomic Ryd- DOI. -
![Arxiv:1805.08185V2 [Physics.Atom-Ph] 21 Jan 2021 Δω Δα Δµ = Qα + Qµ](https://docslib.b-cdn.net/cover/7501/arxiv-1805-08185v2-physics-atom-ph-21-jan-2021-%C2%B5-q-q%C2%B5-2637501.webp)
Arxiv:1805.08185V2 [Physics.Atom-Ph] 21 Jan 2021 Δω Δα Δµ = Qα + Qµ
Enhanced sensitivity to ultralight bosonic dark matter in the spectra of the linear radical SrOH Ivan Kozyryev,1, 2, ∗ Zack Lasner,1, 2,† and John M. Doyle1, 2 1Harvard-MIT Center for Ultracold Atoms, Cambridge, MA 02138 2Department of Physics, Harvard University, Cambridge, MA 02138 (Dated: January 22, 2021) Coupling between Standard Model particles and theoretically well-motivated ultralight dark matter (UDM) candidates can lead to time variation of fundamental constants, including the proton-to-electron mass ratio µ ≡ mp=me ≈ 1836. The presence of nearly-degenerate vibrational energy levels of different character in poly- atomic molecules can result in significantly enhanced relative energy shifts in molecular spectra originating from ¶t µ, relaxing experimental complexity required for high-sensitivity measurements. We analyze the am- plification of UDM effects in the spectrum of laser-cooled strontium monohydroxide (SrOH). SrOH was the first polyatomic molecule to be directly laser cooled to sub-millikelvin temperatures [Kozyryev et al., Phys. Rev. Lett. 118, 173201 (2017)], opening the possibility of long experimental coherence times and providing a 3 promising platform for suppressing systematic errors. Because of the high enhancement factors ( Qµ ≈ 10 ), measurements of the X˜ (200) $ X˜ 0310 rovibrational transitions of SrOH in the microwave regime can re- sult in ∼ 10−17 fractional uncertainty in dµ=µ with one day of integration, leading to significantly improved constraints for UDM coupling constants. We also detail how the use of more complex MOR-type radicals with additional vibrational modes arising from larger ligands R could lead to even greater enhancement factors, while still being susceptible to direct laser cooling.