Choosing a Maximum Drift Rate in a SETI Search: Astrophysical Considerations
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ASU Colloquium
New Frontiers in Artifact SETI: Waste Heat, Alien Megastructures, and "Tabby's Star" Jason T Wright Penn State University SESE Colloquium Arizona State University October 4, 2017 Contact (Warner Bros.) What is SETI? • “The Search for Extraterrestrial Intelligence” • A field of study, like cosmology or planetary science • SETI Institute: • Research center in Mountain View, California • Astrobiology, astronomy, planetary science, radio SETI • Runs the Allen Telescope Array • Berkeley SETI Research Center: • Hosted by the UC Berkeley Astronomy Department • Mostly radio astronomy and exoplanet detection • Runs SETI@Home • Runs the $90M Breakthrough Listen Project Communication SETI The birth of Radio SETI 1960 — Cocconi & Morrison suggest interstellar communication via radio waves Allen Telescope Array Operated by the SETI Institute Green Bank Telescope Operated by the National Radio Astronomy Observatory Artifact SETI Dyson (1960) Energy-hungry civilizations might use a significant fraction of available starlight to power themselves Energy is never “used up”, it is just converted to a lower temperature If a civilization collects or generates energy, that energy must emerge at higher entropy (e.g. mid-infrared radiation) This approach is general: practically any energy use by a civilization should give a star (or galaxy) a MIR excess IRAS All-Sky map (1983) The discovery of infrared cirrus complicated Dyson sphere searches. Credit: NASA GSFC, LAMBDA Carrigan reported on the Fermilab Dyson Sphere search with IRAS: Lots of interesting red sources: -
Interstellar Communication: the Case for Spread Spectrum
Interstellar Communication: The Case for Spread Spectrum David G Messerschmitta aDepartment of Electrical Engineering and Computer Sciences, 253 Cory Hall, University of California, Berkeley, California 94720-1770, USA, [email protected], 1-925-465-5740 Abstract Spread spectrum, widely employed in modern digital wireless terrestrial radio systems, chooses a signal with a noise-like character and much higher bandwidth than necessary. This paper advocates spread spectrum modulation for interstellar communication, motivated by robust immunity to radio- frequency interference (RFI) of technological origin in the vicinity of the receiver while preserving full detection sensitivity in the presence of natural sources of noise. Receiver design for noise immunity alone provides no basis for choosing a signal with any specific character, therefore failing to reduce ambiguity. By adding RFI to noise immunity as a design objective, the conjunction of choice of signal (by the transmitter) together with optimum detection for noise immunity (in the receiver) leads through simple probabilistic argument to the conclusion that the signal should possess the statistical properties of a burst of white noise, and also have a large time-bandwidth product. Thus spread spectrum also provides an implicit coordination between transmitter and receiver by reducing the ambiguity as to the signal character. This strategy requires the receiver to guess the specific noise-like signal, and it is contended that this is feasible if an appropriate pseudorandom signal is generated algorithmically. For example, conceptually simple algorithms like the binary expansion of common irrational numbers like π are shown to be suitable. Due to its deliberately wider bandwidth, spread spectrum is more susceptible to dispersion and distortion in propagation through the interstellar medium, desirably reducing ambiguity in parameters like bandwidth and carrier frequency. -
The Search for Extraterrestrial Intelligence
THE SEARCH FOR EXTRATERRESTRIAL INTELLIGENCE Are we alone in the universe? Is the search for extraterrestrial intelligence a waste of resources or a genuine contribution to scientific research? And how should we communicate with other life-forms if we make contact? The search for extraterrestrial intelligence (SETI) has been given fresh impetus in recent years following developments in space science which go beyond speculation. The evidence that many stars are accompanied by planets; the detection of organic material in the circumstellar disks of which planets are created; and claims regarding microfossils on Martian meteorites have all led to many new empirical searches. Against the background of these dramatic new developments in science, The Search for Extraterrestrial Intelligence: a philosophical inquiry critically evaluates claims concerning the status of SETI as a genuine scientific research programme and examines the attempts to establish contact with other intelligent life-forms of the past thirty years. David Lamb also assesses competing theories on the origin of life on Earth, discoveries of ex-solar planets and proposals for space colonies as well as the technical and ethical issues bound up with them. Most importantly, he considers the benefits and drawbacks of communication with new life-forms: how we should communicate and whether we could. The Search for Extraterrestrial Intelligence is an important contribution to a field which until now has not been critically examined by philosophers. David Lamb argues that current searches should continue and that space exploration and SETI are essential aspects of the transformative nature of science. David Lamb is honorary Reader in Philosophy and Bioethics at the University of Birmingham. -
Astrobiology and the Search for Life Beyond Earth in the Next Decade
Astrobiology and the Search for Life Beyond Earth in the Next Decade Statement of Dr. Andrew Siemion Berkeley SETI Research Center, University of California, Berkeley ASTRON − Netherlands Institute for Radio Astronomy, Dwingeloo, Netherlands Radboud University, Nijmegen, Netherlands to the Committee on Science, Space and Technology United States House of Representatives 114th United States Congress September 29, 2015 Chairman Smith, Ranking Member Johnson and Members of the Committee, thank you for the opportunity to testify today. Overview Nearly 14 billion years ago, our universe was born from a swirling quantum soup, in a spectacular and dynamic event known as the \big bang." After several hundred million years, the first stars lit up the cosmos, and many hundreds of millions of years later, the remnants of countless stellar explosions coalesced into the first planetary systems. Somehow, through a process still not understood, the laws of physics guiding the unfolding of our universe gave rise to self-replicating organisms − life. Yet more perplexing, this life eventually evolved a capacity to know its universe, to study it, and to question its own existence. Did this happen many times? If it did, how? If it didn't, why? SETI (Search for ExtraTerrestrial Intelligence) experiments seek to determine the dis- tribution of advanced life in the universe through detecting the presence of technology, usually by searching for electromagnetic emission from communication technology, but also by searching for evidence of large scale energy usage or interstellar propulsion. Technology is thus used as a proxy for intelligence − if an advanced technology exists, so to does the ad- vanced life that created it. -
The Radio Search for Technosignatures in the Decade 2020–2030
Astro2020 Science White Paper The radio search for technosignatures in the decade 2020–2030 Background photo: central region of the Galaxy by Yuri Beletsky, Carnegie Las Campanas Observatory Thematic Area: Planetary Systems Principal Author: Name: Jean-Luc Margot Institution: University of California, Los Angeles Email: [email protected] Phone: 310.206.8345 Co-authors: Steve Croft (University of California, Berkeley), T. Joseph W. Lazio (Jet Propulsion Laboratory), Jill Tarter (SETI Institute), Eric J. Korpela (University of California, Berkeley) March 11, 2019 1 Scientific context Are we alone in the universe? This question is one of the most profound scientific questions of our time. All life on Earth is related to a common ancestor, and the discovery of other forms of life will revolutionize our understanding of living systems. On a more philosophical level, it will transform our perception of humanity’s place in the cosmos. Observations with the NASA Kepler telescope have shown that there are billions of habitable worlds in our Galaxy [e.g., Borucki, 2016]. The profusion of planets, coupled with the abundance of life’s building blocks in the universe, suggests that life itself may be abundant. Currently, the two primary strategies for the search for life in the universe are (1) searching for biosignatures in the Solar System or around nearby stars and (2) searching for technosignatures emitted from sources in the Galaxy and beyond [e.g., National Academies of Sciences, Engineer- ing, and Medicine, 2018]. Given our present knowledge of astrobiology, there is no compelling reason to believe that one strategy is more likely to succeed than the other. -
Searching for Extraterrestrial Intelligence
THE FRONTIERS COLLEctION THE FRONTIERS COLLEctION Series Editors: A.C. Elitzur L. Mersini-Houghton M. Schlosshauer M.P. Silverman J. Tuszynski R. Vaas H.D. Zeh The books in this collection are devoted to challenging and open problems at the forefront of modern science, including related philosophical debates. In contrast to typical research monographs, however, they strive to present their topics in a manner accessible also to scientifically literate non-specialists wishing to gain insight into the deeper implications and fascinating questions involved. Taken as a whole, the series reflects the need for a fundamental and interdisciplinary approach to modern science. Furthermore, it is intended to encourage active scientists in all areas to ponder over important and perhaps controversial issues beyond their own speciality. Extending from quantum physics and relativity to entropy, consciousness and complex systems – the Frontiers Collection will inspire readers to push back the frontiers of their own knowledge. Other Recent Titles Weak Links Stabilizers of Complex Systems from Proteins to Social Networks By P. Csermely The Biological Evolution of Religious Mind and Behaviour Edited by E. Voland and W. Schiefenhövel Particle Metaphysics A Critical Account of Subatomic Reality By B. Falkenburg The Physical Basis of the Direction of Time By H.D. Zeh Mindful Universe Quantum Mechanics and the Participating Observer By H. Stapp Decoherence and the Quantum-To-Classical Transition By M. Schlosshauer The Nonlinear Universe Chaos, Emergence, Life By A. Scott Symmetry Rules How Science and Nature are Founded on Symmetry By J. Rosen Quantum Superposition Counterintuitive Consequences of Coherence, Entanglement, and Interference By M.P. -
Interstellar Communication. Iii. Optimal Frequency to Maximize Data Rate
Draft version November 17, 2017 INTERSTELLAR COMMUNICATION. III. OPTIMAL FREQUENCY TO MAXIMIZE DATA RATE Michael Hippke1 and Duncan H. Forgan2, 3 1Sonneberg Observatory, Sternwartestr. 32, 96515 Sonneberg, Germany 2SUPA, School of Physics & Astronomy, University of St Andrews, North Haugh, St Andrews, Scotland, KY16 9SS, UK 3St Andrews Centre for Exoplanet Science, University of St Andrews, UK ABSTRACT The optimal frequency for interstellar communication, using \Earth 2017" technology, was derived in papers I and II of this series (Hippke 2017a,b). The framework included models for the loss of photons from diffraction (free space), interstellar extinction, and atmospheric transmission. A major limit of current technology is the focusing of wavelengths λ < 300 nm (UV). When this technological constraint is dropped, a physical bound is found at λ ≈ 1 nm (E ≈ keV) for distances out to kpc. While shorter wavelengths may produce tighter beams and thus higher data rates, the physical limit comes from surface roughness of focusing devices at the atomic level. This limit can be surpassed by beam-forming with electromagnetic fields, e.g. using a free electron laser, but such methods are not energetically competitive. Current lasers are not yet cost efficient at nm wavelengths, with a gap of two orders of magnitude, but future technological progress may converge on the physical optimum. We recommend expanding SETI efforts towards targeted (at us) monochromatic (or narrow band) X-ray emission at 0.5-2 keV energies. 1. INTRODUCTION believed to originate from intelligent beings on Mars. The idea to communicate with Extraterrestrial Intel- In the optical, William Pickering(1909) suggested to ligence was born in the 19th century. -
Nasa and the Search for Technosignatures
NASA AND THE SEARCH FOR TECHNOSIGNATURES A Report from the NASA Technosignatures Workshop NOVEMBER 28, 2018 NASA TECHNOSIGNATURES WORKSHOP REPORT CONTENTS 1 INTRODUCTION .................................................................................................................................................................... 1 What are Technosignatures? .................................................................................................................................... 2 What Are Good Technosignatures to Look For? ....................................................................................................... 2 Maturity of the Field ................................................................................................................................................... 5 Breadth of the Field ................................................................................................................................................... 5 Limitations of This Document .................................................................................................................................... 6 Authors of This Document ......................................................................................................................................... 6 2 EXISTING UPPER LIMITS ON TECHNOSIGNATURES ....................................................................................................... 9 Limits and the Limitations of Limits ........................................................................................................................... -
BREAKTHROUGH LISTEN Searching for Signatures of Technology
BREAKTHROUGH LISTEN Searching for Signatures of Technology Howard Isaacson, Andrew Siemion & the Breakthrough Listen Team Overview Search Results Instrumentation Breakthrough Listen (BL) is the most comprehensive At radio frequencies, the capability of the data recording search for signs of extraterrestrial technology ever In the first analysis of BL data, including 30 minute cycles of observations of system directly determines survey speed, and given a undertaken. Using some of the most powerful 692 targets from our stellar sample, we find that none of the observed systems fixed observing time and spectral coverage, they telescopes in the world, combined with an host high-duty-cycle radio transmitters emitting between 1.1 to 1.9 GHz with an determine survey sensitivity as well. Breakthrough Listen unprecedented capability to record, archive and EIRP of 1013 watts, a luminosity readily achievable by our own civilization. This has the ability to write data to disk at the rate of 24 GB analyze the incoming data, Breakthrough Listen is comprehensive search over hundreds of stars represents only a small piece of per second. Using commodity servers and consumer humanity’s best hope of detecting evidence for the ever growing data set being compiled by Breakthrough Listen. class hard drives, the BL backend can record 6 GHz of technological civilizations beyond the Earth. BL his bandwidth at 8 bits for two polarizations. In a typical 6 currently observing a focused target list consisting hour session, the raw data recorded to disk can exceed ~1700 nearby stars and ~150 nearby galaxies. Our 350 TB. Using GPU processors the data volume is observing strategy is expressly designed to to allow Target Selection reduced to 2% of the raw data volume in less than 6 us to to effectively work through the mountains of hours. -
Astrobiology and the Search for Life Beyond Earth in the Next Decade
ASTROBIOLOGY AND THE SEARCH FOR LIFE BEYOND EARTH IN THE NEXT DECADE HEARING BEFORE THE COMMITTEE ON SCIENCE, SPACE, AND TECHNOLOGY HOUSE OF REPRESENTATIVES ONE HUNDRED FOURTEENTH CONGRESS FIRST SESSION September 29, 2015 Serial No. 114–40 Printed for the use of the Committee on Science, Space, and Technology ( Available via the World Wide Web: http://science.house.gov U.S. GOVERNMENT PUBLISHING OFFICE 97–759PDF WASHINGTON : 2016 For sale by the Superintendent of Documents, U.S. Government Publishing Office Internet: bookstore.gpo.gov Phone: toll free (866) 512–1800; DC area (202) 512–1800 Fax: (202) 512–2104 Mail: Stop IDCC, Washington, DC 20402–0001 COMMITTEE ON SCIENCE, SPACE, AND TECHNOLOGY HON. LAMAR S. SMITH, Texas, Chair FRANK D. LUCAS, Oklahoma EDDIE BERNICE JOHNSON, Texas F. JAMES SENSENBRENNER, JR., ZOE LOFGREN, California Wisconsin DANIEL LIPINSKI, Illinois DANA ROHRABACHER, California DONNA F. EDWARDS, Maryland RANDY NEUGEBAUER, Texas SUZANNE BONAMICI, Oregon MICHAEL T. MCCAUL, Texas ERIC SWALWELL, California MO BROOKS, Alabama ALAN GRAYSON, Florida RANDY HULTGREN, Illinois AMI BERA, California BILL POSEY, Florida ELIZABETH H. ESTY, Connecticut THOMAS MASSIE, Kentucky MARC A. VEASEY, Texas JIM BRIDENSTINE, Oklahoma KATHERINE M. CLARK, Massachusetts RANDY K. WEBER, Texas DON S. BEYER, JR., Virginia BILL JOHNSON, Ohio ED PERLMUTTER, Colorado JOHN R. MOOLENAAR, Michigan PAUL TONKO, New York STEPHEN KNIGHT, California MARK TAKANO, California BRIAN BABIN, Texas BILL FOSTER, Illinois BRUCE WESTERMAN, Arkansas BARBARA COMSTOCK, Virginia GARY PALMER, Alabama BARRY LOUDERMILK, Georgia RALPH LEE ABRAHAM, Louisiana DARIN LAHOOD, Illinois (II) C O N T E N T S September 29, 2015 Page Witness List ............................................................................................................. 2 Hearing Charter ..................................................................................................... -
GNU Radio Update 2019
GNU Radio Project Update Ben Hilburn Ticket Sales Ticket 100 150 200 250 300 350 50 0 2019-03-23 2019-03-26 2019-04-06 2019-04-11 2019-04-13 2019-04-15 2019-04-24 2019-04-26 2019-04-29 2019-05-01 2019-05-13 2019-05-23 2019-05-29 2019-06-06 2019-06-12 2019-06-18 2019-06-26 Purchases Ticket GRCon 2019-06-28 2019-06-30 2019-07-08 2019-07-10 2019-07-15 2019-07-19 2019-07-23 2019-07-26 2019-07-29 2019-07-31 2019-08-02 2019-08-05 2019-08-07 2019-08-09 2019-08-12 2019-08-14 2019-08-18 2019-08-20 2019-08-22 2019-08-24 2019-08-26 2019-08-28 2019-08-30 2019-09-01 2019-09-03 2019-09-05 Big News: 3.8 • Huge changelog with many significant updates! • More than 200+ contributors in the changelog. • The release announcement garnered significant attention & Not least of which is Python 3 migration! interest. Radio Society of Great Britain Magazine Credit: Derek Kozel Yes, 3.8 has squiggly lines. Of course the examples *just work*! Credit: James Horton Out of Tree Modules and 3.8 • Update your OOTMs! • The GNU Radio Wiki has a v3.8.0.0 OOT Module Porting Guide • Thanks to Bastian Bloessl for authoring the guide! Credit: Clayton Smith, @argilo The Stats Slide • Unique Cloners: 34% increase • Unique Visitors: 11% increase Stat 2017 2018 2019 YOY Executed CLAs 5 11 28 155% Closed Issues 68 140 221 58% Closed Pull Requests 177 272 443 63% Summer Coding Programs • Google Summer of Code • Arpit Gupta: Block Header Parsing Tool • Mentor: Nicolas Cuervo • Auto-parse your block header into GRC YAML! • Bowen Hu: gr-Verilog • Mentors: Sebastian Kowslowski, Marcus Mueller • Cycle-accurate simulation of Verilog files from GRC! • See their posters in the expo! • Special thanks to Felix Wunsch for running GSoC! GNU Radio Signals Challenge • We released a SigMF recording containing three hidden messages. -
Full Curriculum Vitae
Jason Thomas Wright—CV Department of Astronomy & Astrophysics Phone: (814) 863-8470 Center for Exoplanets and Habitable Worlds Fax: (814) 863-2842 525 Davey Lab email: [email protected] Penn State University http://sites.psu.edu/astrowright University Park, PA 16802 @Astro_Wright US Citizen, DOB: 2 August 1977 ORCiD: 0000-0001-6160-5888 Education UNIVERSITY OF CALIFORNIA, BERKELEY PhD Astrophysics May 2006 Thesis: Stellar Magnetic Activity and the Detection of Exoplanets Adviser: Geoffrey W. Marcy MA Astrophysics May 2003 BOSTON UNIVERSITY BA Astronomy and Physics (mathematics minor) summa cum laude May 1999 Thesis: Probing the Magnetic Field of the Bok Globule B335 Adviser: Dan P. Clemens Awards and fellowships NASA Group Achievement Award for NEID 2020 Drake Award 2019 Dean’s Climate and Diversity Award 2012 Rock Institute Ethics Fellow 2011-2012 NASA Group Achievement Award for the SIM Planet Finding Capability Study Team 2008 University of California Hewlett Fellow 1999-2000, 2003-2004 National Science Foundation Graduate Research Fellow 2000-2003 UC Berkeley Outstanding Graduate Student Instructor 2001 Phi Beta Kappa 1999 Barry M. Goldwater Scholar 1997 Last updated — Jan 15, 2021 1 Jason Thomas Wright—CV Positions and Research experience Associate Department Head for Development July 2020–present Astronomy & Astrophysics, Penn State University Director, Penn State Extraterrestrial Intelligence Center March 2020–present Professor, Penn State University July 2019 – present Deputy Director, Center for Exoplanets and Habitable Worlds July 2018–present Astronomy & Astrophysics, Penn State University Acting Director July 2020–August 2021 Associate Professor, Penn State University July 2015 – June 2019 Associate Department Head for Diversity and Equity August 2017–August 2018 Astronomy & Astrophysics, Penn State University Visiting Associate Professor, University of California, Berkeley June 2016 – June 2017 Assistant Professor, Penn State University Aug.