Inventory of CO2 Available for Terraforming Mars

Total Page:16

File Type:pdf, Size:1020Kb

Inventory of CO2 Available for Terraforming Mars PERSPECTIVE https://doi.org/10.1038/s41550-018-0529-6 Inventory of CO2 available for terraforming Mars Bruce M. Jakosky 1,2* and Christopher S. Edwards3 We revisit the idea of ‘terraforming’ Mars — changing its environment to be more Earth-like in a way that would allow terres- trial life (possibly including humans) to survive without the need for life-support systems — in the context of what we know about Mars today. We want to answer the question of whether it is possible to mobilize gases present on Mars today in non- atmospheric reservoirs by emplacing them into the atmosphere, and increase the pressure and temperature so that plants or humans could survive at the surface. We ask whether this can be achieved considering realistic estimates of available volatiles, without the use of new technology that is well beyond today’s capability. Recent observations have been made of the loss of Mars’s atmosphere to space by the Mars Atmosphere and Volatile Evolution Mission probe and the Mars Express space- craft, along with analyses of the abundance of carbon-bearing minerals and the occurrence of CO2 in polar ice from the Mars Reconnaissance Orbiter and the Mars Odyssey spacecraft. These results suggest that there is not enough CO2 remaining on Mars to provide significant greenhouse warming were the gas to be emplaced into the atmosphere; in addition, most of the CO2 gas in these reservoirs is not accessible and thus cannot be readily mobilized. As a result, we conclude that terraforming Mars is not possible using present-day technology. he concept of terraforming Mars has been a mainstay of sci- Could the remaining planetary inventories of CO2 be mobi- ence fiction for a long time, but it also has been discussed from lized and emplaced into the atmosphere via current or plausible 1 a scientific perspective, initially by Sagan and more recently near-future technologies? Would the amount of CO2 that could T 2 by, for example, McKay et al. The idea has resurfaced lately in pub- be emplaced into the atmosphere provide any significant green- lic discussions of possible human missions to Mars and long-term house warming? human colonization3. Here we take ‘terraforming’ to mean chang- Our analysis follows that of ref. 2, but benefits from 20 years of ing the Martian environment into one that could be more suitable additional spacecraft observations of Mars. These data have pro- for the existence of terrestrial life. Following McKay et al.2, this has vided substantial new information on the volatile history of the two possible approaches. First, we can consider increasing the pres- planet, the abundance of volatiles locked up on and below the sur- sure enough to allow humans to work without the use of pressure face, and the loss of gas from the atmosphere to space. suits; this approach does not necessarily require an oxygen atmo- sphere that can be breathed directly. Second, we can increase the Reservoirs and sinks for CO2 abundance of an atmospheric greenhouse gas enough such that the Non-atmospheric CO2 reservoirs or sinks that we examine here temperature will increase to the point at which liquid water can be include: polar CO2 ice or water-ice clathrate, CO2 adsorbed onto stable or persist. Having warmer temperatures and stable liquid mineral grains in the regolith, carbon-bearing minerals (in carbon- water could greatly simplify all aspects of operations in the Martian ate-bearing rocks), and the permanent loss of CO2 from the atmo- environment. Both aspects require the addition of significant quan- sphere to space. Below we will discuss the amount of CO2 necessary tities of gas to the present atmosphere. to raise temperatures sufficiently to allow liquid water; for now, CO2 and H2O are the only greenhouse gases that are likely to be however, take a nominal requirement as being about 1 bar of CO2, –2 present on Mars today in sufficient abundance to provide any sig- which is equivalent to about 2,500 g CO2 cm in the atmosphere. nificant greenhouse warming. While other gases such as introduced For comparison, the present-day atmosphere has an average pres- –2 chlorofluorocarbons have been proposed as ways to raise the atmo- sure of about 6 mbar — equivalent to about 15 g CO2 cm at the spheric temperature2,4–6, these are short-lived and without a feasible surface. source using current technologies; they are therefore not considered further here. Previous models of atmospheric warming have dem- Polar CO2 ice and clathrate. The Martian polar caps contain a sea- onstrated that water cannot provide significant warming by itself; sonal covering of CO2 ice that deposits in winter when the surface temperatures do not allow enough water to persist as vapour with- drops below the condensation temperature of atmospheric CO2, 7 out first having significant warming by CO2 (ref. ). CH4 and H2 and disappears in summer when sunlight causes it to sublimate back have been proposed as possible greenhouse gases that contributed into the atmosphere. This seasonal covering can contain as much as to warming early Mars7, but these are not expected to be present in perhaps a third of the atmosphere at any given time, or the equiva- an accessible location on Mars today. Thus, we focus on determin- lent of about 2 mbar (ref. 8). ing the inventory of CO2 on present-day Mars, and whether the CO2 The Martian north polar cap loses its entire covering of CO2 ice that is present in non-atmospheric reservoirs can be put back into during summer, exposing a residual polar cap. This cap consists the atmosphere. broadly of water ice with intermixed dust in various proportions to To understand the availability and impact of CO2 gas on atmo- form layers in a stack up to several kilometres thick. The ice cap is spheric warming, we address the following questions. Where has surrounded by layered deposits that are thought to contain little to 9 the CO2 from an ancient, thicker greenhouse atmosphere gone? no water ice, down to a latitude of about 80° (ref. ). 1Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO, USA. 2Department of Geological Sciences, University of Colorado, Boulder, CO, USA. 3Department of Physics and Astronomy, Northern Arizona University, Flagstaff, AZ, USA. *e-mail: [email protected] 634 NATURE ASTronomY | VOL 2 | AUGUST 2018 | 634–639 | www.nature.com/natureastronomy NATURE ASTRONOMY PERSPECTIVE The south polar cap retains a thin and spatially discontinuous 0.020 T = 200 K cover of CO2 ice after the seasonal frost has disappeared during summer. This ice is not thought to be substantial, containing only the equivalent of a fraction of the present-day atmospheric CO2 8 Palagonite abundance . Water ice is observed to be present beneath that CO2, and much of the volume of the polar deposits is thought to be water ice with intermixed dust. Within the volume of the polar deposits, however, radar measurements show what appears to be a substan- 10 tial volume of clean CO2 ice buried at depth . This volume of ice, 0.015 if emplaced into the atmosphere, would provide enough CO2 to double the atmospheric pressure, to an estimated 12 mbar (ref. 11). H2O and CO2 can also occur in a clathrate structure, in which 12 the H2O molecules form a ‘cage’ that can hold CO2 (ref. ). The H2O shell contains six molecules for every CO2 molecule trapped inside. Clathrates can be stable in the Martian polar regions13, although there’s no evidence to suggest that they are actually present. If the full volume of the polar ice deposits consisted of H2O–CO2 clath- rate, they could contain up to the equivalent of about 150 mbar of 0.010 CO2. Even if clathrate is present, however, it’s unlikely that the entire per gram adsorbent (g) polar deposit could have formed in a way that allowed them to be 2 fully populated with CO2. Such a deposit would require high CO2 pressures to have been present throughout the formation process14. Although it’s not possible to obtain a more realistic estimate of the Adsorbed CO possible CO2 content of the polar deposit, 150 mbar should be con- sidered as an extreme upper limit, and it’s possible that there is no clathrate present at all. Nontronite Furthermore, liquid CO2 is not considered to be a viable reser- 0.005 voir for polar-region CO2. The pressure is above the triple-point pressure for liquid CO2 at a depth of only a few kilometres in the polar regions15. However, temperatures are too low to allow liquid CO2 until a depth that would be well below the ice and deep within the crust. CO2 clathrate or liquid CO2 can exist within the crust in non- polar regions, based solely on their stability phase diagram14. However, for either to be present in significant quantities, the Basalt CO2 pressure in pore spaces in the crust would have to be equal to the lithostatic pressure from the overlying materials; this is not 0 5 10 likely and, were the pores sealed in a way that allowed this, the Pressure (mbar) CO2 would be effectively sequestered in the subsurface and thus 14 rendered inaccessible . Fig. 1 | CO2 adsorption isotherms for palagonite, nontronite and basalt. Credit: adapted from ref. 16, Elsevier Adsorbed CO2. Both CO2 and H2O can be adsorbed onto individual grains in the regolith and megaregolith16,17. This process involves a physical (as opposed to chemical) bonding at the level of the indi- vidual molecule. The amount of gas that can adsorb onto a grain some instances to depths of 8 km (ref.
Recommended publications
  • Journal Issue 26 | October 2019
    journal Issue 26 | October 2019 Communicating Astronomy with the Public Spotlighting a Black Hole What did it take to create the largest outreach campaign for an astronomical result? Tactile Subaru A project to make telescope technology accessible Naming ExoWorlds Update on the IAU100 NameExoWorlds campaign www.capjournal.org As part of the 100th anniversary commemorations, the International Astronomical Union (IAU) is organising the IAU100 NameExoWorlds global competition to allow any country in the world to give a popular name to a selected exoplanet and its News News host star. The final results of the competion will be announced in Decmeber 2019. Credit: IAU/L. Calçada. Editorial Welcome to the 26th edition of the CAPjournal! To start off, the first part of 2019 brought in a radical new era in astronomy with the first ever image showing a shadow of a black hole. For CAPjournal #26, part of the team who collaborated on the promotion of this image hs written a piece to show what it took to produce one of the largest astronomy outreach campaigns to date. We also highlight two other large outreach campaigns in this edition. The first is a peer-reviewed article about the 2016 solar eclipse in Indonesia from the founder of the astronomy website lagiselatan, Avivah Yamani. Next, an update on NameExoWorlds, the largest IAU100 campaign, as we wait for the announcement of new names for the ExoWorlds in December. Additionally, this issue touches on opportunities for more inclusive astronomy. We bring you a peer-reviewed article about outreach for inclusion by Dr. Kumiko Usuda-Sato and the speech “Diversity Across Astronomy Can Further Our Research” delivered by award-winning astronomy communicator Dr.
    [Show full text]
  • Mars 2020 Radiological Contingency Planning
    National Aeronautics and Space Administration Mars 2020 Radiological Contingency Planning NASA plans to launch the Mars 2020 rover, produce the rover’s onboard power and to Perseverance, in summer 2020 on a mission warm its internal systems during the frigid to seek signs of habitable conditions in Mars’ Martian night. ancient past and search for signs of past microbial life. The mission will lift off from Cape NASA prepares contingency response plans Canaveral Air Force Station in Florida aboard a for every launch that it conducts. Ensuring the United Launch Alliance Atlas V launch vehicle safety of launch-site workers and the public in between mid-July and August 2020. the communities surrounding the launch area is the primary consideration in this planning. The Mars 2020 rover design is based on NASA’s Curiosity rover, which landed on Mars in 2012 This contingency planning task takes on an and greatly increased our knowledge of the added dimension when the payload being Red Planet. The Mars 2020 rover is equipped launched into space contains nuclear material. to study its landing site in detail and collect and The primary goal of radiological contingency store the most promising samples of rock and planning is to enable an efficient response in soil on the surface of Mars. the event of an accident. This planning is based on the fundamental principles of advance The system that provides electrical power for preparation (including rehearsals of simulated Mars 2020 and its scientific equipment is the launch accident responses), the timely availability same as for the Curiosity rover: a Multi- of technically accurate and reliable information, Mission Radioisotope Thermoelectric Generator and prompt external communication with the (MMRTG).
    [Show full text]
  • The Ethics of Terraforming and Areoforming in an Age of Climate Change
    Engineering Planets, Engineering Ourselves: The Ethics of Terraforming and Areoforming in an Age of Climate Change Patrick D. Murphy (University of Central Florida)1 Abstract The concept of terraforming, the engineered transformation of alien planets into habitats suitable for human settlement, has taken on new meaning in science fiction and contemporary culture as climate change has indicated that human beings are currently transforming this planet but without a clear plan for sustaining inhabitability. Literary depictions by Kim Stanley Robinson of both climate change and terraforming raise ethical questions about the engineering of this and other planets, while the science fiction novels of Joan Slonczewski raise ethical questions about engineering human beings to adapt to alien environments. Together, they provide ways of thinking about the intertwined ethical questions of engineering the biosphere and engineering the species in the context of human and environmental sustainability. In particular, some works, such as the novels of Karen Traviss, raise the issue of how much the human species might have to engineer itself to pay the price of its unplanned engineering of planet Earth. Nearly twenty years ago Bill McKibben claimed that "we are at the end of nature" (8). In support of this seemingly hyperbolic statement, he referred to a 1957 scientific paper which claimed that "Human beings are now carrying out a large scale geophysical experiment" (qtd. in McKibben 10), by pumping rapidly increasing amounts of carbon dioxide into the atmosphere. 1 Patrick Murphy, Department of English, University of Central Florida, Building: CNH301 P.O. Box 161346 Orlando, FL 32816-1346 [email protected] 54 Many people, myself included, thought McKibben had gone over the top.
    [Show full text]
  • The War of the Worlds Postcolonialism, Americanism, and Terrorism in Modern Science Fiction Film
    Durkstra 4167430 | 1 The War of the Worlds Postcolonialism, Americanism, and Terrorism in Modern Science Fiction Film Sytse Durkstra English Language and Culture Supervisor | Chris Louttit Sytse Durkstra | s4167430 | Email [email protected] Durkstra 4167430 | 2 ENGLISH LANGUAGE AND CULTURE Teacher who will receive this document: Chris Louttit Title of document: The War of the Worlds: Postcolonialism, Americanism, and Terrorism in Modern Science Fiction Film Name of course: BA Thesis English Language and Culture Date of submission: 15 June 2015 The work submitted here is the sole responsibility of the undersigned, who has neither committed plagiarism nor colluded in its production. Signed Name of student: Sytse Durkstra Student number: 4167430 Durkstra 4167430 | 3 And this Thing I saw! How can I describe it? A monstrous tripod, higher than many houses, striding over the young pine trees, and smashing them aside in its career; a walking engine of glittering metal, reeling now across the heather, articulate ropes of steel dangling from it, and the clattering tumult of its passage mingling with the riot of the thunder. A flash, and it came out vividly, heeling over one way with two feet in the air, to vanish and reappear almost instantly, as it seemed with the next flash, a hundred yards nearer. - H.G. Wells, The War of the Worlds But who shall dwell in these worlds if they be inhabited? . Are we or they Lords of the World? . And how are all things made for man? - Kepler In our obsession with antagonisms of the moment, we often forget how much unites all the members of humanity.
    [Show full text]
  • The Past Decade and the Future of Cosmology and Astrophysics
    Towards a New Enlightenment? A Transcendent Decade The Past Decade and the Future of Cosmology and Astrophysics Martin Rees Martin Rees is a cosmologist and space scientist. After studying at Cambridge University, he held various posts in the UK and elsewhere, before returning to Cambridge, where he has been a professor, Head of the Institute of Astronomy, and Master of Trinity College. He has contributed to our understanding of galaxy formation, black holes, high-energy phenomena in the cosmos, and the concept of the multiverse. He has received substantial international recognition for his research. He has been much involved in science-related policy, being a member of the UK’s House of Lords and (during 2005–10) President of the Royal Society, the independent scientific academy of the UK Martin Rees and the Commonwealth. Apart from his research publications, he writes and University of Cambridge lectures widely for general audiences, and is the author of eight books, the most recent being On the Future (2018). Recommended books: Universe, Martin Rees, Dorling Kindersley, 2012; On the Future, Martin Rees, Princeton University Press, 2018. In the last decade, there has been dramatic progress in exploring the cosmos. Highlights include close-up studies of the planets and moons of our Solar System; and (even more dramatic) the realization that most stars are orbited by planets, and that there may be millions of Earth-like planets in our Galaxy. On a still larger scale, we have achieved a better understanding of how galaxies have developed, over 13.8 billion years of cosmic history, from primordial fluctuations.
    [Show full text]
  • Patrick Thaddeus
    PUBLISHED: 19 JUNE 2017 | VOLUME: 1 | ARTICLE NUMBER: 0170 obituary Patrick Thaddeus A pioneer in the field of astrochemistry, Patrick Thaddeus discovered dozens of exotic molecules in space and helped revolutionize our view of the interstellar medium and star formation. atrick Thaddeus did more than anyone telescope operating from a rooftop just a else to demonstrate, as he was fond few hundred yards from Broadway. After Pof saying, that chemistry was not a over two decades of steady mapping with provincial subject that stopped five miles this instrument and a near-duplicate one above our heads. As a pioneer in the field that they installed in Chile in 1982, Pat and of astrochemistry, his elegant laboratory his students obtained what is still today work provided ironclad identifications the most extensive and widely used survey of hundreds of new molecules of of the molecular Milky Way. More than astronomical interest, and his observational 40 years later, both telescopes continue to programme discovered about one-sixth yield important scientific results, including of the ~200 molecules known to exist in the discovery over the past decade of two space. His early recognition that carbon THOMAS DAME new spiral arm features of the Galaxy. monoxide would be an excellent tracer of A total of 24 PhD dissertations have the cold dense regions of space led directly been written based on observations or to the discovery of giant molecular clouds instrumental work with the two telescopes. and a revolution in our understanding of In 1986, Pat, along with several the interstellar medium and star formation.
    [Show full text]
  • MARS 2020, CANDIDATES LANDING SITES, EXOMARS and THEIR RELATIONSHIP to MARS SAMPLE RETURN 10:25 A.M
    2nd International Mars Sample Return 2018 (LPI Contrib. No. 2071) sess303.pdf Thursday, April 26, 2018 MARS 2020, CANDIDATES LANDING SITES, EXOMARS AND THEIR RELATIONSHIP TO MARS SAMPLE RETURN 10:25 a.m. Forum This session will present a status report on the Mars 2020 sample-caching rover, its candidate landing sites, the Exomars rover mission, and the relationship of all of these to Mars Sample Return. Chairs: Victoria Hipkin (Canadian Space Agency, Canada) Briony Horgan (Purdue University, USA) 10:25 a.m. Williford K. * *Jet Propulsion Laboratory, California Institute of Technology, USA The NASA Mars 2020 Rover Mission The NASA Mars 2020 rover mission will explore an astrobiologically relevant site to characterize its geology, evaluate past habitability, seek signs of ancient life, and assemble a returnable cache of samples. An overview of technical capabilities and scientific strategy in development will be presented with a focus on the role envisioned for Mars 2020 in a possible Mars sample return campaign. 10:45 a.m. Schulte M. * Meyer M. Grant J. Golombek M. *NASA Headquarters, USA The Mars 2020 Rover Mission Landing Site Candidates [#6026] The number of suitable landing sites for the Mars 2020 rover mission has been narrowed to three leading candidates: Jezero Crater, NE Syrtis, and Columbia Hills. Each offers geologic settings with the potential for preservation of biosignatures. 11:00 a.m. Vago J. L. * Svedhem H. Sefton-Nash E. Kminek G. Ruesch O. Haldemann A. F. C. Rodionov D. ExoMars Science Working Team *European Space Agency ExoMars Contributions to Mars Sample Return [#6021] Each of the two ExoMars missions has the potential to make discoveries that could inform and perhaps influence our collective strategy for a future Mars Sample Return mission.
    [Show full text]
  • List Stranica 1 Od
    list product_i ISSN Primary Scheduled Vol Single Issues Title Format ISSN print Imprint Vols Qty Open Access Option Comment d electronic Language Nos per volume Available in electronic format 3 Biotech E OA C 13205 2190-5738 Springer English 1 7 3 Fully Open Access only. Open Access. Available in electronic format 3D Printing in Medicine E OA C 41205 2365-6271 Springer English 1 3 1 Fully Open Access only. Open Access. 3D Display Research Center, Available in electronic format 3D Research E C 13319 2092-6731 English 1 8 4 Hybrid (Open Choice) co-published only. with Springer New Start, content expected in 3D-Printed Materials and Systems E OA C 40861 2363-8389 Springer English 1 2 1 Fully Open Access 2016. Available in electronic format only. Open Access. 4OR PE OF 10288 1619-4500 1614-2411 Springer English 1 15 4 Hybrid (Open Choice) Available in electronic format The AAPS Journal E OF S 12248 1550-7416 Springer English 1 19 6 Hybrid (Open Choice) only. Available in electronic format AAPS Open E OA S C 41120 2364-9534 Springer English 1 3 1 Fully Open Access only. Open Access. Available in electronic format AAPS PharmSciTech E OF S 12249 1530-9932 Springer English 1 18 8 Hybrid (Open Choice) only. Abdominal Radiology PE OF S 261 2366-004X 2366-0058 Springer English 1 42 12 Hybrid (Open Choice) Abhandlungen aus dem Mathematischen Seminar der PE OF S 12188 0025-5858 1865-8784 Springer English 1 87 2 Universität Hamburg Academic Psychiatry PE OF S 40596 1042-9670 1545-7230 Springer English 1 41 6 Hybrid (Open Choice) Academic Questions PE OF 12129 0895-4852 1936-4709 Springer English 1 30 4 Hybrid (Open Choice) Accreditation and Quality PE OF S 769 0949-1775 1432-0517 Springer English 1 22 6 Hybrid (Open Choice) Assurance MAIK Acoustical Physics PE 11441 1063-7710 1562-6865 English 1 63 6 Russian Library of Science.
    [Show full text]
  • The Terraforming Timeline. A. J. Berliner1 and C. P. Mckay2
    Planetary Science Vision 2050 Workshop 2017 (LPI Contrib. No. 1989) 8031.pdf The Terraforming Timeline. A. J. Berliner1 and C. P. McKay2, 1University of California Berkeley, Berkeley, CA 94704, [email protected], 2Space Sciences Division, NASA Ames Research Center, Mountain View, CA 94075. Introduction: Terraforming, the transformation of particularly the winter South Polar Cap, and any CO2 a planet so as to resemble the earth so that it can sup- that is absorbed into the cold ground in the polar re- port widespread life, has been described as a grand gions. Once the warming starts all this releasable CO2 challenge of both space sciences and synthetic biology will go into the atmosphere. Thus, it is important to [1,2]. We propose the following abstract on a Martian know the total before warming starts. Current esti- Terraforming timeline as a guide to shaping planetary mates of the releasable CO2 on Mars today range from science research over the coming century. a little more than the present thin atmosphere to values Terraforming Mars can be divided into two phases. sufficient to create a pressure on Mars equal to the sea The first phase is warming the planet from the present level pressure on Earth. Nitrogen is a fundamental re- average surface temperature of -60ºC to a value close quirement for life and necessary constituent of a to Earth’s average temperature to +15ºC, and re- breathable atmosphere. The recent discovery by the creating a thick CO2 atmosphere [3,4,5,6] This warm- Curiosity Rover of nitrate in the soil on Mars (~0.03% ing phase is relatively easy and quick, and could take by mass) is therefore encouraging for terraforming [7].
    [Show full text]
  • Mars Reconnaissance Orbiter Maneuver Plan for Mars 2020 Entry, Descent, and Landing Support and Beyond
    Jet Propulsion Laboratory California Ins5tute of Technology Mars Reconnaissance Orbiter Maneuver Plan for Mars 2020 Entry, Descent, and Landing Support and Beyond Sean Wagner Premkumar Menon AAS/AIAA Space Flight Mechanics Meeting Ka'anapali, HI January 13{17, 2019 AAS Paper 19-233 c 2019 California Institute of Technology. U.S. Government sponsorship acknowledged. Jet Propulsion Laboratory MarsCalifornia Ins5tute of Technology Reconnaissance Orbiter Project Mars Reconnaissance Orbiter Mission The Mars Reconnaissance Orbiter launched on August 12, 2005 from the Cape Canaveral Air Force Station and arrived at Mars on March 10, 2006. After aerobraking, MRO began the Primary Science Phase (PSP) in November 2006 and continues to perform science observations at Mars. MRO Spacecraft: Spacecraft Bus: 3-axis stabilized ACS system; 3-meter diameter High Gain Antenna; hydrazine propulsion system Instrument Suite: HiRISE Camera, CRISM Imaging Spectrometer, Mars Climate Sounder, Mars Color Imager, Context Camera, Shallow Subsurface Radar, Electra Proximity Link Payload (among other instrument payloads) January 15, 2019 MRO Maneuver Plan for Mars 2020 EDL Support and Beyond SVW { 3 MRO Primary Science Orbit (PSO) The MRO PSO is designed to satisfy science and mission requirements; the spacecraft is flown in an orbit designed to optimize the science instruments performance. The MRO PSO is defined by three key characteristics: Sun-synchronous orbit ascending node at 3:00 PM ± 15 minutes Local Mean Solar Time (LMST) (daylight equatorial crossing) Periapsis
    [Show full text]
  • Science Fiction Stories with Good Astronomy & Physics
    Science Fiction Stories with Good Astronomy & Physics: A Topical Index Compiled by Andrew Fraknoi (U. of San Francisco, Fromm Institute) Version 7 (2019) © copyright 2019 by Andrew Fraknoi. All rights reserved. Permission to use for any non-profit educational purpose, such as distribution in a classroom, is hereby granted. For any other use, please contact the author. (e-mail: fraknoi {at} fhda {dot} edu) This is a selective list of some short stories and novels that use reasonably accurate science and can be used for teaching or reinforcing astronomy or physics concepts. The titles of short stories are given in quotation marks; only short stories that have been published in book form or are available free on the Web are included. While one book source is given for each short story, note that some of the stories can be found in other collections as well. (See the Internet Speculative Fiction Database, cited at the end, for an easy way to find all the places a particular story has been published.) The author welcomes suggestions for additions to this list, especially if your favorite story with good science is left out. Gregory Benford Octavia Butler Geoff Landis J. Craig Wheeler TOPICS COVERED: Anti-matter Light & Radiation Solar System Archaeoastronomy Mars Space Flight Asteroids Mercury Space Travel Astronomers Meteorites Star Clusters Black Holes Moon Stars Comets Neptune Sun Cosmology Neutrinos Supernovae Dark Matter Neutron Stars Telescopes Exoplanets Physics, Particle Thermodynamics Galaxies Pluto Time Galaxy, The Quantum Mechanics Uranus Gravitational Lenses Quasars Venus Impacts Relativity, Special Interstellar Matter Saturn (and its Moons) Story Collections Jupiter (and its Moons) Science (in general) Life Elsewhere SETI Useful Websites 1 Anti-matter Davies, Paul Fireball.
    [Show full text]
  • Valuing Life Detection Missions Edwin S
    Valuing life detection missions Edwin S. Kite* (University of Chicago), Eric Gaidos (University of Hawaii), Tullis C. Onstott (Princeton University). * [email protected] Recent discoveries imply that Early Mars was habitable for life-as-we-know-it (Grotzinger et al. 2014); that Enceladus might be habitable (Waite et al. 2017); and that many stars have Earth- sized exoplanets whose insolation favors surface liquid water (Dressing & Charbonneau 2013, Gaidos 2013). These exciting discoveries make it more likely that spacecraft now under construction – Mars 2020, ExoMars rover, JWST, Europa Clipper – will find habitable, or formerly habitable, environments. Did these environments see life? Given finite resources ($10bn/decade for the US1), how could we best test the hypothesis of a second origin of life? Here, we first state the case for and against flying life detection missions soon. Next, we assume that life detection missions will happen soon, and propose a framework (Fig. 1) for comparing the value of different life detection missions: Scientific value = (Reach × grasp × certainty × payoff) / $ (1) After discussing each term in this framework, we conclude that scientific value is maximized if life detection missions are flown as hypothesis tests. With hypothesis testing, even a nondetection is scientifically valuable. Should the US fly more life detection missions? Once a habitable environment has been found and characterized, life detection missions are a logical next step. Are we ready to do this? The case for emphasizing habitable environments, not life detection: Our one attempt to detect life, Viking, is viewed in hindsight as premature or at best uncertain. In-space life detection experiments are expensive.
    [Show full text]