Have We Found Other Earths?
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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: -
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. -
Dynamics of the Arecibo Radio Telescope
DYNAMICS OF THE ARECIBO RADIO TELESCOPE Ramy Rashad 110030106 Department of Mechanical Engineering McGill University Montreal, Quebec, Canada February 2005 Under the supervision of Professor Meyer Nahon Abstract The following thesis presents a computer and mathematical model of the dynamics of the tethered subsystem of the Arecibo Radio Telescope. The computer and mathematical model for this part of the Arecibo Radio Telescope involves the study of the dynamic equations governing the motion of the system. It is developed in its various components; the cables, towers, and platform are each modeled in succession. The cable, wind, and numerical integration models stem from an earlier version of a dynamics model created for a different radio telescope; the Large Adaptive Reflector (LAR) system. The study begins by converting the cable model of the LAR system to the configuration required for the Arecibo Radio Telescope. The cable model uses a lumped mass approach in which the cables are discretized into a number of cable elements. The tower motion is modeled by evaluating the combined effective stiffness of the towers and their supporting backstay cables. A drag model of the triangular truss platform is then introduced and the rotational equations of motion of the platform as a rigid body are considered. The translational and rotational governing equations of motion, once developed, present a set of coupled non-linear differential equations of motion which are integrated numerically using a fourth-order Runge-Kutta integration scheme. In this manner, the motion of the system is observed over time. A set of performance metrics of the Arecibo Radio Telescope is defined and these metrics are evaluated under a variety of wind speeds, directions, and turbulent conditions. -
Vol 25 No 3, Summer 2019
SearchLites Vol. 25 No. 3, Summer 2019 The Quarterly Newsletter of The SETI League, Inc. Offices: 433 Liberty Street In Memoriam: Little Ferry NJ Dr. Owen K. Garriott, W5LFL 07643 USA 22 November 1930 – 15 April 2019 Phone: (201) 641-1770 Facsimile: (201) 641-1771 Email: [email protected] Web: www.setileague.org President Richard Factor Registered Agent: Anthony Agnello Secretary/Treasurer: A. Heather Wood Executive Director Emeritus: H. Paul Shuch, Ph.D. Trustee: Martin Schreiber, CPA Advisory Board: Anthony Agnello KT6W photo Greg Bear Paul Davies, Ph.D. The SETI League is saddened to report the death in April of Owen Garriott, Robert S. Dixon, Ph.D. Frank D. Drake, Ph.D. W5LFL, at age 88. Owen was an electrical engineering professor at Stanford, a Claudio Maccone, Ph.D. Skylab and Space Shuttle astronaut, and a lifelong radio amateur. In December Clifford Stoll, Ph.D. 1983, he became the first ham to operate in space. In this early 1984 picture, Owen is exchanging QSL cards with H. Paul Shuch (now SETI League Executive Direc- SearchLites, ISSN 1096-5599, tor Emeritus), following Owen's historic STS-9 mission. is the Quarterly Newsletter of The SETI League, Inc., a membership-supported, non- Garriott became a licensed radio amateur at the age of 15. It was ham radio profit [501(c)(3)], educational that prompted him to become an electrical engineer, and ultimately one of NASA’s and scientific corporation, dedi- first scientist-astronauts in 1965. He joined the space program after having served cated to the electromagnetic Search for Extra-Terrestrial as an electronics officer in the US navy, and as a professor of electrical engineer- Intelligence. -
SETI@Home Completes a Decade of ET Search 1 May 2009
SETI@home completes a decade of ET search 1 May 2009 Over the years, improvements to the Arecibo telescope have significantly improved the quality of data available to SETI@home, and the continuous increase in the speed of the average PC has made it possible to use more sensitive and sophisticated analysis techniques. Today, SETI@home continues its search for evidence of extraterrestrial life, with greater sensitivity than ever, and its hundreds of thousands of volunteers continue to engage in lively on-line forums and in a spirited competition The SETI@home project, which has involved the for most data processed. worldwide public in a search for radio-wave evidence of life outside Earth, marks its 10th More information: anniversary on May 17, 2009. setiathome.berkeley.edu/index.php The project, based at the Space Sciences Provided by SETI@home Laboratory at the University of California, Berkeley, records and analyzes data from the world's largest radio telescope, the Arecibo Observatory in Puerto Rico. The collected computing power of hundreds of thousands of volunteer PCs is used to search this data for narrow-band signals (similar to TV or cell-phone transmissions) and other types of signals of possible extraterrestrial origin. SETI@home was conceived in 1995. Development began in 1998, with initial funding from The Planetary Society and Paramount Pictures. It was publicly launched on May 17, 1999, and the number of volunteers quickly grew to about one million. Because of the presence of noise and man-made radio interference, SETI@home doesn't get excited by individual signals. -
Why SETI Will Fail ‡
Why SETI Will Fail z B. Zuckerman1 1Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA E-mail: [email protected] Abstract. The union of space telescopes and interstellar spaceships guarantees that if extraterrestrial civilizations were common, someone would have come here long ago. PACS numbers: 97.10.Tk arXiv:1912.08386v1 [physics.pop-ph] 18 Dec 2019 z This article originally appeared in the September/October 2002 issue of Mercury magazine (published by the Astronomical Society of the Pacific). Why SETI Will Fail 2 1. Introduction Where do humans stand on the scale of cosmic intelligence? For most people, this question ranks at or very near the top of the list of "scientific things I would like to know." Lacking hard evidence to constrain the imagination, optimists conclude that technological civilizations far in advance of our own are common in our Milky Way Galaxy, whereas pessimists argue that we Earthlings probably have the most advanced technology around. Consequently, this topic has been debated endlessly and in numerous venues. Unfortunately, significant new information or ideas that can point us in the right direction come along infrequently. But recently I have realized that important connections exist between space astronomy and space travel that have never been discussed in the scientific or popular literature. These connections clearly favor the more pessimistic scenario mentioned above. Serious radio searches for extraterrestrial intelligence (SETI) have been conducted during the past few decades. Brilliant scientists have been associated with SETI, starting with pioneers like Frank Drake and the late Carl Sagan and then continuing with Paul Horowitz, Jill Tarter, and the late Barney Oliver. -
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 ........................................................................................................................... -
The Search for Extra-Terrestial Intelligence in the New Millennium Transcript
The Search for Extra-Terrestial Intelligence in the New Millennium Transcript Date: Thursday, 3 April 2008 - 12:00AM THE SEARCH FOR EXTRA-TERRESTRIAL INTELLIGENCE IN THE NEW MILLENNIUM Professor Ian Morison SETI, the Search for Extra-terrestrial Intelligence, has now been actively pursued for close on 50 years without success. However this does not imply that we are alone in the Milky Way galaxy for, although most astronomers now agree that intelligent civilisations are far less common than once thought, we cannot say that there are none. But it does mean that they are likely to be at greater distances from us and, as yet, we have only seriously searched a tiny region of our galaxy. It will not be until the 2020's that an instrument, now on the drawing board, will give us the capability to detect radio signals of realistic power from across the whole galaxy. It is also possible that light, rather than radio, might be the communication carrier chosen by an alien race, but optical-SETI searches seeking out pulsed laser signals have only just begun. The story so far The subject may well have been inspired by the building of the 76m Mk1 radio telescope at Jodrell Bank in 1957. In 1959 two American astronomers, Guccione and Morrison, submitted a paper to the journal Nature in which they pointed out that, given two radio telescopes of comparable size to the Mk 1, it would be possible to communicate across interstellar distances by radio. They suggested a number of possible nearby, sun-like, stars that could be observed to see if any signals might be detected. -
Kepler Press
National Aeronautics and Space Administration PRESS KIT/FEBRUARY 2009 Kepler: NASA’s First Mission Capable of Finding Earth-Size Planets www.nasa.gov Media Contacts J.D. Harrington Policy/Program Management 202-358-5241 NASA Headquarters [email protected] Washington 202-262-7048 (cell) Michael Mewhinney Science 650-604-3937 NASA Ames Research Center [email protected] Moffett Field, Calif. 650-207-1323 (cell) Whitney Clavin Spacecraft/Project Management 818-354-4673 Jet Propulsion Laboratory [email protected] Pasadena, Calif. 818-458-9008 (cell) George Diller Launch Operations 321-867-2468 Kennedy Space Center, Fla. [email protected] 321-431-4908 (cell) Roz Brown Spacecraft 303-533-6059. Ball Aerospace & Technologies Corp. [email protected] Boulder, Colo. 720-581-3135 (cell) Mike Rein Delta II Launch Vehicle 321-730-5646 United Launch Alliance [email protected] Cape Canaveral Air Force Station, Fla. 321-693-6250 (cell) Contents Media Services Information .......................................................................................................................... 5 Quick Facts ................................................................................................................................................... 7 NASA’s Search for Habitable Planets ............................................................................................................ 8 Scientific Goals and Objectives ................................................................................................................. -
Panoramic Optical and Near-Infrared SETI Instrument: Overall Specifications and Science Program
Panoramic optical and near-infrared SETI instrument: overall specifications and science program Shelley A. Wrighta,b, Paul Horowitzc,J´erˆomeMairea,DanWerthimerd, Franklin Antonioe, Michael Aronsonf,MarenCosensa,b,FrankD.Drakeg, Andrew W. Howardh, Geo↵rey W. Marcyd,RickRa↵antii, Andrew P. V. Siemiond,g,j,k,RemingtonP.S.Stonel,RichardR. Tre↵ersm, Avinash Uttamchandanic,SamChaim-Weismannd, a Center for Astrophysics & Space Sciences, University of California San Diego, USA; b Department of Physics, University of California San Diego, USA; c Department of Physics, Harvard University, USA; d Department of Astronomy, University of California Berkeley, CA, USA; e Qualcomm Research Center, 5775 Morehouse Dr, San Diego, CA, USA; f Electronic Packaging Man, Encinitas, CA, USA g SETI Institute, Mountain View, USA; h Astronomy Department, California Institute of Technology, USA; i Techne Instruments, Berkeley, CA, USA; j Radboud University, Nijmegen , Netherlands; kInstitute of Space Sciences and Astronomy, University of Malta; l University of California Observatories, Lick Observatory, USA; m Starman Systems, Alamo, USA; n Space Sciences Laboratory, University of California Berkeley, CA, USA ABSTRACT We present overall specifications and science goals for a new optical and near-infrared (350 - 1650 nm) instru- ment designed to greatly enlarge the current Search for Extraterrestrial Intelligence (SETI) phase space. The Pulsed All-sky Near-infrared Optical SETI (PANOSETI) observatory will be a dedicated SETI facility that aims to increase sky area searched, wavelengths covered, number of stellar systems observed, and duration of time monitored. This observatory will o↵er an “all-observable-sky” optical and wide-field near-infrared pulsed tech- nosignature and astrophysical transient search that is capable of surveying the entire northern hemisphere. -
Kepler Spies Most Earth-Like Planet Yet NASA Mission Finds a Potentially Rocky World Orbiting a Star That Resembles the Sun
IN FOCUS NEWS The programme will also provide valuable edges, where the ice tends to be warmer, thicker the coast to track large-scale ice loss over five information on the physical characteristics of and full of crevices. “It’s still a challenge to get years. Analysing that ice loss in light of the new glacier ice. Last December, geophysicist Beata the mass of these glaciers,” she says. topographical and oceanographic data will help Csatho of the University at Buffalo in New York When the aerial phase of OMG begins next researchers to determine where, and to what and her colleagues reported using surface- year, planes will fly inland from the coast, taking extent, deeper saltwater currents affect glaciers. elevation data to estimate how much ice mass measurements of slight changes in gravitational Lipscomb says that all these OMG data Greenland had lost between 1993 and 2012 pull that can be used to produce low-resolution should help modellers as they incorporate (B. M. Csatho et al. Proc. Natl Acad. Sci. USA maps of the topography under both water and ocean–ice interactions around Greenland 111, 18478–18483; 2014). The data were fairly ice. Planes will also drop more than 200 temper- into their models. That work is still in its early reliable over the island’s interior, Csatho says, ature and salinity probes into fjords and coastal stages, he says, “but the data that they are get- but measurements were more difficult along its waters, and take radar measurements along ting in this project is exactly what we need”.