Astrobiology and the Search for Life in the Universe
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SETI Is Part of Astrobiology
SETI is Part of Astrobiology Jason T. Wright Department of Astronomy & Physics Center for Exoplanets and Habitable Worlds Penn State University Phone: (814) 863-8470 [email protected] I. SETI is Part of Astrobiology “Traditional SETI is not part of astrobiology” declares the NASA Astrobiology Strategy 2015 document (p. 150). This is incorrect.1 Astrobiology is the study of life in the universe, in particular its “origin, evolution, distribution, and future in the universe.” [emphasis mine] Searches for biosignatures are searches for the results of interactions between life and its environment, and could be sensitive to even primitive life on other worlds. As such, these searches focus on the origin and evolution of life, using past life on Earth as a guide. But some of the most obvious ways in which Earth is inhabited today are its technosignatures such as radio transmissions, alterations of its atmosphere by industrial pollutants, and probes throughout the Solar System. It seems clear that the future of life on Earth includes the development of ever more obvious technosignatures. Indeed, the NASA Astrobiology Strategy 2015 document acknowledges “the possibility” that such technosignatures exist, but erroneously declares them to be “not part of contemporary SETI,” and mentions them only to declare that we should “be aware of the possibility” and to “be sure to include [technosignatures] as a possible kind of interpretation we should consider as we begin to get data on the exoplanets.” In other words, while speculation on the nature of biosignatures and the design of multi-billion dollar missions to find those signatures is consistent with NASA’s vision for astrobiology, speculation on the nature of technosignatures and the design of observations to find them is not. -
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: -
Defenses That Hurt Science ______By Avi Loeb on June 4, 2021
Defenses That Hurt Science _______ By Avi Loeb on June 4, 2021 In the highlighted subtitle of a recent New-York Times Op-Ed, Bret Stephens stated: "Sometimes science is hurt most by those who think they are defending it". This sentiment resonates with many examples that go beyond the topic of his Op-Ed. Let me elaborate. When the nitrogen iceberg model was proposed recently to explain the weird properties of the first interstellar object `Oumuamua, it was immediately embraced by mainstream astronomers with a sigh of relief that the anomalous object was finally explained. We had never seen a chunk of frozen nitrogen floating within the Solar system before, and being detected first - `Oumuamua should represent the most common type of objects ejected by other planetary systems; but this was of little concern for the advocates. Shortly afterwards, my student Amir Siraj and I posted a paper showing that this model requires much more raw material of heavy elements than available in stars within the Milky Way galaxy. This was not a reflection on the previously noted abundance problem for interstellar objects, but a specific deficiency of the nitrogen model - which associates `Oumuamua with a fragment chipped off the surface of a Pluto-like planet around another star. The limited supply of nitrogen on exo-Pluto surfaces and the requirement that the interstellar journey would last just half a billion years - or else most of the nitrogen would evaporate, leads to a mass budget problem. But why should the mainstream worry about a fundamental drawback when the agenda is to sideline the weirdness of `Oumuamua? In another recent Op-Ed, Seth Shostak from the SETI Institute downgraded the scientific credentials of the anticipated report on Unidentified Flying Objects (UFOs), to be delivered by the Pentagon and various intelligence agencies to Congress this month. -
Lecture-29 (PDF)
Life in the Universe Orin Harris and Greg Anderson Department of Physics & Astronomy Northeastern Illinois University Spring 2021 c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 1 / 95 Overview Dating Rocks Life on Earth How Did Life Arise? Life in the Solar System Life Around Other Stars Interstellar Travel SETI Review c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 2 / 95 Dating Rocks Zircon Dating Sedimentary Grand Canyon Life on Earth How Did Life Arise? Life in the Solar System Life Around Dating Rocks Other Stars Interstellar Travel SETI Review c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 3 / 95 Zircon Dating Zircon, (ZrSiO4), minerals incorporate trace amounts of uranium but reject lead. Naturally occuring uranium: • U-238: 99.27% • U-235: 0.72% Decay chains: • 238U −→ 206Pb, τ =4.47 Gyrs. • 235U −→ 207Pb, τ = 704 Myrs. 1956, Clair Camron Patterson dated the Canyon Diablo meteorite: τ =4.55 Gyrs. c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 4 / 95 Dating Sedimentary Rocks • Relative ages: Deeper layers were deposited earlier • Absolute ages: Decay of radioactive isotopes old (deposited last) oldest (depositedolder first) c 2012-2021 G. Anderson., O. Harris Universe: Past, Present & Future – slide 5 / 95 Grand Canyon: Earth History from 200 million - 2 billion yrs ago. Dating Rocks Life on Earth Earth History Timeline Late Heavy Bombardment Hadean Shark Bay Stromatolites Cyanobacteria Q: Earliest Fossils? Life on Earth O2 History Q: Life on Earth How Did Life Arise? Life in the Solar System Life Around Other Stars Interstellar Travel SETI Review c 2012-2021 G. -
Bayesian Analysis of the Astrobiological Implications of Life's
Bayesian analysis of the astrobiological implications of life's early emergence on Earth David S. Spiegel ∗ y, Edwin L. Turner y z ∗Institute for Advanced Study, Princeton, NJ 08540,yDept. of Astrophysical Sciences, Princeton Univ., Princeton, NJ 08544, USA, and zInstitute for the Physics and Mathematics of the Universe, The Univ. of Tokyo, Kashiwa 227-8568, Japan Submitted to Proceedings of the National Academy of Sciences of the United States of America Life arose on Earth sometime in the first few hundred million years Any inferences about the probability of life arising (given after the young planet had cooled to the point that it could support the conditions present on the early Earth) must be informed water-based organisms on its surface. The early emergence of life by how long it took for the first living creatures to evolve. By on Earth has been taken as evidence that the probability of abiogen- definition, improbable events generally happen infrequently. esis is high, if starting from young-Earth-like conditions. We revisit It follows that the duration between events provides a metric this argument quantitatively in a Bayesian statistical framework. By (however imperfect) of the probability or rate of the events. constructing a simple model of the probability of abiogenesis, we calculate a Bayesian estimate of its posterior probability, given the The time-span between when Earth achieved pre-biotic condi- data that life emerged fairly early in Earth's history and that, billions tions suitable for abiogenesis plus generally habitable climatic of years later, curious creatures noted this fact and considered its conditions [5, 6, 7] and when life first arose, therefore, seems implications. -
Optical SETI: the All-Sky Survey
Professor van der Veen Project Scientist, UCSB Department of Physics, Experimental Cosmology Group class 4 [email protected] frequencies/wavelengths that get through the atmosphere The Planetary Society http://www.planetary.org/blogs/jason-davis/2017/20171025-seti-anybody-out-there.html THE ATMOSPHERE'S EFFECT ON ELECTROMAGNETIC RADIATION Earth's atmosphere prevents large chunks of the electromagnetic spectrum from reaching the ground, providing a natural limit on where ground-based observatories can search for SETI signals. Searching for technology that we have, or are close to having: Continuous radio searches Pulsed radio searches Targeted radio searches All-sky surveys Optical: Continuous laser and near IR searches Pulsed laser searches a hypothetical laser beacon watch now: https://www.youtube.com/watch?time_continue=41&v=zuvyhxORhkI Theoretical physicist Freeman Dyson’s “First Law of SETI Investigations:” Every search for alien civilizations should be planned to give interesting results even when no aliens are discovered. Interview with Carl Sagan from 1978: Start at 6:16 https://www.youtube.com/watch?v=g- Q8aZoWqF0&feature=youtu.be Anomalous signal recorded by Big Ear Telescope at Ohio State University. Big Ear was a flat, aluminum dish three football fields wide, with reflectors at both ends. Signal was at 1,420 MHz, the hydrogen 21 cm ‘spin flip’ line. http://www.bigear.org/Wow30th/wow30th.htm May 15, 2015 A Russian observatory reports a strong signal from a Sun-like star. Possibly from advanced alien civilization. The RATAN-600 radio telescope in Zelenchukskaya, at the northern foot of the Caucasus Mountains location: star HD 164595 G-type star (like our Sun) 94.35 ly away, visually located in constellation Hercules 1 planet that orbits it every 40 days unusual radio signal detected – 11 GHz (2.7 cm) claim: Signal from a Type II Kardashev civilization Only one observation Not confirmed by other telescopes Russian Academy of Sciences later retracted the claim that it was an ETI signal, stating the signal came from a military satellite. -
Messengers from Outer Space
The complete absence of national laboratories for standardizing radiation measurements and the lack of physics departments in most radiotherapy centres in Latin America warrant the setting up of one or more regional dosimetry facilities, the functions of which would be primarily to calibrate dosimeters; to provide local technical assistance by means of trained staff; to check radiation equipment and dosimeters; to arrange a dose-intercomparison service; and to co-operate with local personnel dosimetry services. To be most effective, this activity should be in the charge of local personnel, with some initial assistance in the form of equipment and experts provided by the Agency. Although the recommendations were presented to the IAEA as the or ganization responsible for the setting up of the panel, the participants re commended that the co-operation of the World Health Organization and the Pan-American Health Organization should be invited. It was also suggested that the panel report be circulated to public health authorities in the countries represented. MESSENGERS FROM OUTER SPACE Although no evidence has yet been confirmed of living beings reaching the earth from space, it has been estimated that hundreds of tons of solid matter arrive every day in the form of meteorites or cosmic dust particles. Much is destroyed by heat in the atmosphere but fragments recovered can give valuable information about what has been happening in the universe for billions of years. Some of the results of worldwide research on meteorites were given at a symposium in Vienna during August. During six days of discussions a total of 73 scientific papers was present ed and a special meeting was held for the purpose of improving international co-operation in the research. -
The Water on Mars Vanished. This Might Be Where It Went
The water on Mars vanished. This might be where it went. timesofindia.indiatimes.com/home/science/the-water-on-mars-vanished-this-might-be-where- it-went-/articleshow/81599751.cms NYT News Service | Mar 20, 2021, 10:32 IST Mars was once wet, with an ocean’s worth of water on its surface. Today, most of Mars is as dry as a desert except for ice deposits in its polar regions. Where did the rest of the water go? Some of it disappeared into space. Water molecules, pummeled by particles of solar wind, broke apart into hydrogen and oxygen atoms, and those, especially the lighter hydrogen atoms, sped out of the atmosphere, lost to outer space. A tall outcropping of rock, with layered deposits of sediments in the distance, marking a remnant of an ancient, long-vanished river delta in Jezero Crater, are pictured in this undated image taken by NASA's Mars rover Perseverance. (Reuters) But most of the water, a new study concludes, went down, sucked into the red planet’s rocks. And there it remains, trapped within minerals and salts. Indeed, as much as 99% of the water that once flowed on Mars could still be there, the researchers estimated in a paper published this week in the journal Science. Data from the past two decades of robotic missions to Mars, including NASA ’s Curiosity rover and the Mars Reconnaissance Orbiter, showed a wide distribution of what geologists call hydrated minerals. “It became very, very clear that it was common and not rare to find evidence of water alteration,” said Bethany Ehlmann, a professor of planetary science at the California Institute of Technology and one of the authors of the paper. -
A Direct Communication Proposal to Test the Zoo Hypothesis
Space Policy 38 (2016) 22e26 Contents lists available at ScienceDirect Space Policy journal homepage: www.elsevier.com/locate/spacepol Viewpoint A direct communication proposal to test the Zoo Hypothesis Joao~ Pedro de Magalhaes~ Institute of Integrative Biology, University of Liverpool, Biosciences Building, Room 245, Crown Street, Liverpool, L69 7ZB, UK article info abstract Article history: Whether we are alone in the universe is one of the greatest mysteries facing humankind. Given the >100 Received 3 March 2016 billion stars in our galaxy, many have argued that it is statistically unlikely that life, including intelligent Accepted 16 June 2016 life, has not emerged anywhere else. The lack of any sign of extraterrestrial intelligence, even though on a Available online 26 July 2016 cosmic timescale extraterrestrial civilizations would have enough time to cross the galaxy, is known as Fermi's Paradox. One possible explanation for Fermi's Paradox is the Zoo Hypothesis which states that Keywords: one or more extraterrestrial civilizations know of our existence and can reach us, but have chosen not to Active SETI disturb us or even make their existence known to us. I propose here a proactive test of the Zoo Hy- Astrobiology fi Fermi's Paradox pothesis. Speci cally, I propose to send a message using television and radio channels to any extrater- Messaging to extraterrestrial intelligence restrial civilization(s) that might be listening and inviting them to respond. Even though I accept this is METI unlikely to be successful in the sense of resulting in a response from extraterrestrial intelligences, the possibility that extraterrestrial civilizations are monitoring us cannot be dismissed and my proposal is consistent with current scientific knowledge. -
After the Financial Crisis: Ongoing Challenges Facing Delphi Retirees
AFTER THE FINANCIAL CRISIS: ONGOING CHALLENGES FACING DELPHI RETIREES FIELD HEARING BEFORE THE SUBCOMMITTEE ON OVERSIGHT AND INVESTIGATIONS OF THE COMMITTEE ON FINANCIAL SERVICES U.S. HOUSE OF REPRESENTATIVES ONE HUNDRED ELEVENTH CONGRESS SECOND SESSION JULY 13, 2010 Printed for the use of the Committee on Financial Services Serial No. 111–143 ( U.S. GOVERNMENT PRINTING OFFICE 61–847 PDF WASHINGTON : 2010 For sale by the Superintendent of Documents, U.S. Government Printing 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 VerDate Nov 24 2008 18:29 Nov 12, 2010 Jkt 061847 PO 00000 Frm 00001 Fmt 5011 Sfmt 5011 K:\DOCS\61847.TXT TERRIE HOUSE COMMITTEE ON FINANCIAL SERVICES BARNEY FRANK, Massachusetts, Chairman PAUL E. KANJORSKI, Pennsylvania SPENCER BACHUS, Alabama MAXINE WATERS, California MICHAEL N. CASTLE, Delaware CAROLYN B. MALONEY, New York PETER T. KING, New York LUIS V. GUTIERREZ, Illinois EDWARD R. ROYCE, California NYDIA M. VELA´ ZQUEZ, New York FRANK D. LUCAS, Oklahoma MELVIN L. WATT, North Carolina RON PAUL, Texas GARY L. ACKERMAN, New York DONALD A. MANZULLO, Illinois BRAD SHERMAN, California WALTER B. JONES, JR., North Carolina GREGORY W. MEEKS, New York JUDY BIGGERT, Illinois DENNIS MOORE, Kansas GARY G. MILLER, California MICHAEL E. CAPUANO, Massachusetts SHELLEY MOORE CAPITO, West Virginia RUBE´ N HINOJOSA, Texas JEB HENSARLING, Texas WM. LACY CLAY, Missouri SCOTT GARRETT, New Jersey CAROLYN MCCARTHY, New York J. GRESHAM BARRETT, South Carolina JOE BACA, California JIM GERLACH, Pennsylvania STEPHEN F. LYNCH, Massachusetts RANDY NEUGEBAUER, Texas BRAD MILLER, North Carolina TOM PRICE, Georgia DAVID SCOTT, Georgia PATRICK T. -
CQ Committee Guide
SPECIAL REPORT Committee Guide Complete House and senate RosteRs: 113tH CongRess, seCond session DOUGLAS GRAHAM/CQ ROLL CALL THE PEOPLE'S BUSINESS: The House Energy and Commerce Committee, in its Rayburn House Office Building home, marks up bills on Medicare and the Federal Communications Commission in July 2013. www.cq.com | MARCH 24, 2014 | CQ WEEKLY 431 09comms-cover layout.indd 431 3/21/2014 5:12:22 PM SPECIAL REPORT Senate Leadership: 113th Congress, Second Session President of the Senate: Vice President Joseph R. Biden Jr. President Pro Tempore: Patrick J. Leahy, D-Vt. DEMOCRATIC LEADERS Majority Leader . Harry Reid, Nev. Steering and Outreach Majority Whip . Richard J. Durbin, Ill. Committee Chairman . Mark Begich, Alaska Conference Vice Chairman . Charles E. Schumer, N.Y. Chief Deputy Whip . Barbara Boxer, Calif. Policy Committee Chairman . Charles E. Schumer, N.Y. Democratic Senatorial Campaign Conference Secretary . Patty Murray, Wash. Committee Chairman . Michael Bennet, Colo. REPUBLICAN LEADERS Minority Leader . Mitch McConnell, Ky. Policy Committee Chairman . John Barrasso, Wyo. Minority Whip . John Cornyn, Texas Chief Deputy Whip . Michael D. Crapo, Idaho Conference Chairman . John Thune, S.D. National Republican Senatorial Conference Vice Chairman . Roy Blunt, Mo. Committee Chairman . Jerry Moran, Kan. House Leadership: 113th Congress, Second Session Speaker of the House: John A. Boehner, R-Ohio REPUBLICAN LEADERS Majority Leader . Eric Cantor, Va. Policy Committee Chairman . James Lankford, Okla. Majority Whip . Kevin McCarthy, Calif. Chief Deputy Whip . Peter Roskam, Ill. Conference Chairwoman . .Cathy McMorris Rodgers, Wash. National Republican Congressional Conference Vice Chairwoman . Lynn Jenkins, Kan. Committee Chairman . .Greg Walden, Ore. Conference Secretary . Virginia Foxx, N.C. -
Dr. Seth Shostak
Written Text for Congressional Testimony Advances in the Search for Life Seth Shostak, Senior Astronomer, SETI Institute 189 Bernardo Ave., #200, Mountain View, CA 94043, [email protected] It is no longer considered foolish to argue that biology could exist on some of the trillion other planets in our galaxy. Its discovery would produce a lasting change in our perceptions, demonstrating that life is not confined to our world. We would know that biology is not some sort of miracle, but a commonplace – an ubiquitous, cosmic infection. The discovery of intelligence elsewhere would be of even greater import, as we have always considered humans to be special, even the pinnacle of Creation. To learn that there are others out there – others whose cognitive abilities exceed our own – would be a discovery that would recalibrate how our species views itself. It would also have consequences that can be only vaguely gauged, in much the way that the discovery of the New World led to societal changes that were largely unpredictable at the time of its happening. However, the search for extraterrestrial intelligence, known by the acronym SETI, has been pursued for more than a half century with no unambiguous, positive result. We haven’t found conclusive proof of any intelligent (or even unintelligent) life beyond the confines of Earth. Claims that our planet is being visited by alien beings, while popular with the citizenry, are not considered credible by most scientists. However, recent developments in both astronomy and technology are accelerating the speed of SETI searches, and it is hardly fantastic to suggest that we could find evidence of cosmic company within a few decades.