Habitability and Life Parameters in Our Solar System *
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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. -
Lennon Reunion, Page 6 “There Will Be a Huge Transformation of the Page 2 July 4, 2013 TORRANCE TRIBUNE Calendar People FRIDAY, JULY 5 Torrance Blvd
The Weekly Newspaper of Torrance Herald Publications - Torrance, El Segundo, Manhattan Beach, Hawthorne, Lawndale, & Inglewood Community Newspapers Since 1911 - (310) 322-1830 - Vol. 3, No. 26 - July 4, 2013 Torrance Salutes Independence Inside Day Sans Fireworks Show This Issue Business & Professional ......................10 Calendar...............................2 Classifieds ...........................9 Crossword/Sudoku ............9 Police Reports ....................3 Politically Speaking ...........4 Real Estate. .......................12 The fourth of July, the most American of holidays, was again marked without parades or city-sponsored fireworks due to budget cuts but it did not stop residents from celebrating. Seen here is a skydiver with the American flag at the Torrance Centennial Celebration. Photo by TerriAnn Ferren. Sports ...................................5 City Council Previews Del Amo TerriAnn in Torrance .........6 Fashion Center Renovations By Dylan Little mall. The mall will not look anywhere near and going to other places in Southern California On Tuesday, the Torrance City Council heard how it looks today,” said Scotto. “When 2015 to shop, they’re going to stop in Torrance at a presentation from Simon Property Group on comes around, I think people will be extremely our Del Amo Mall. Come Thanksgiving this planned upgrades to the Del Amo Fashion pleased with the results we’re going to have year, we’ll get the first taste of that with the Center. Chuck Davis with Simon Property Group with this mall. Instead of driving by our mall See City Council, page 2 made a PowerPoint presentation that showed a nearly unrecognizable mall. One of the major Weekend changes was to divide the mall into the “Fashion Center” (focusing on clothes and high-end retail) TerriAnn: A Lennon and “Market Square” (focusing on home goods Forecast and furniture). -
The Search for Another Earth – Part II
GENERAL ARTICLE The Search for Another Earth – Part II Sujan Sengupta In the first part, we discussed the various methods for the detection of planets outside the solar system known as the exoplanets. In this part, we will describe various kinds of exoplanets. The habitable planets discovered so far and the present status of our search for a habitable planet similar to the Earth will also be discussed. Sujan Sengupta is an 1. Introduction astrophysicist at Indian Institute of Astrophysics, Bengaluru. He works on the The first confirmed exoplanet around a solar type of star, 51 Pe- detection, characterisation 1 gasi b was discovered in 1995 using the radial velocity method. and habitability of extra-solar Subsequently, a large number of exoplanets were discovered by planets and extra-solar this method, and a few were discovered using transit and gravi- moons. tational lensing methods. Ground-based telescopes were used for these discoveries and the search region was confined to about 300 light-years from the Earth. On December 27, 2006, the European Space Agency launched 1The movement of the star a space telescope called CoRoT (Convection, Rotation and plan- towards the observer due to etary Transits) and on March 6, 2009, NASA launched another the gravitational effect of the space telescope called Kepler2 to hunt for exoplanets. Conse- planet. See Sujan Sengupta, The Search for Another Earth, quently, the search extended to about 3000 light-years. Both Resonance, Vol.21, No.7, these telescopes used the transit method in order to detect exo- pp.641–652, 2016. planets. Although Kepler’s field of view was only 105 square de- grees along the Cygnus arm of the Milky Way Galaxy, it detected a whooping 2326 exoplanets out of a total 3493 discovered till 2Kepler Telescope has a pri- date. -
The Subsurface Habitability of Small, Icy Exomoons J
A&A 636, A50 (2020) Astronomy https://doi.org/10.1051/0004-6361/201937035 & © ESO 2020 Astrophysics The subsurface habitability of small, icy exomoons J. N. K. Y. Tjoa1,?, M. Mueller1,2,3, and F. F. S. van der Tak1,2 1 Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands e-mail: [email protected] 2 SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen, The Netherlands 3 Leiden Observatory, Leiden University, Niels Bohrweg 2, 2300 RA Leiden, The Netherlands Received 1 November 2019 / Accepted 8 March 2020 ABSTRACT Context. Assuming our Solar System as typical, exomoons may outnumber exoplanets. If their habitability fraction is similar, they would thus constitute the largest portion of habitable real estate in the Universe. Icy moons in our Solar System, such as Europa and Enceladus, have already been shown to possess liquid water, a prerequisite for life on Earth. Aims. We intend to investigate under what thermal and orbital circumstances small, icy moons may sustain subsurface oceans and thus be “subsurface habitable”. We pay specific attention to tidal heating, which may keep a moon liquid far beyond the conservative habitable zone. Methods. We made use of a phenomenological approach to tidal heating. We computed the orbit averaged flux from both stellar and planetary (both thermal and reflected stellar) illumination. We then calculated subsurface temperatures depending on illumination and thermal conduction to the surface through the ice shell and an insulating layer of regolith. We adopted a conduction only model, ignoring volcanism and ice shell convection as an outlet for internal heat. -
Can There Be Additional Rocky Planets in the Habitable Zone of Tight Binary
Mon. Not. R. Astron. Soc. 000, 1–10 () Printed 24 September 2018 (MN LATEX style file v2.2) Can there be additional rocky planets in the Habitable Zone of tight binary stars with a known gas giant? B. Funk1⋆, E. Pilat-Lohinger1 and S. Eggl2 1Institute for Astronomy, University of Vienna, Vienna, Austria 2IMCCE, Observatoire de Paris, Paris, France ABSTRACT Locating planets in Habitable Zones (HZs) around other stars is a growing field in contem- porary astronomy. Since a large percentage of all G-M stars in the solar neighborhood are expected to be part of binary or multiple stellar systems, investigations of whether habitable planets are likely to be discovered in such environments are of prime interest to the scientific community. As current exoplanet statistics predicts that the chances are higher to find new worlds in systems that are already known to have planets, we examine four known extrasolar planetary systems in tight binaries in order to determine their capacity to host additional hab- itable terrestrial planets. Those systems are Gliese 86, γ Cephei, HD 41004 and HD 196885. In the case of γ Cephei, our results suggest that only the M dwarf companion could host ad- ditional potentially habitable worlds. Neither could we identify stable, potentially habitable regions around HD 196885A. HD 196885 B can be considered a slightly more promising tar- get in the search forEarth-twins.Gliese 86 A turned out to be a very good candidate, assuming that the system’s history has not been excessively violent. For HD 41004 we have identified admissible stable orbits for habitable planets, but those strongly depend on the parameters of the system. -
Livre-Ovni.Pdf
UN MONDE BIZARRE Le livre des étranges Objets Volants Non Identifiés Chapitre 1 Paranormal Le paranormal est un terme utilisé pour qualifier un en- mé n'est pas considéré comme paranormal par les semble de phénomènes dont les causes ou mécanismes neuroscientifiques) ; ne sont apparemment pas explicables par des lois scien- tifiques établies. Le préfixe « para » désignant quelque • Les différents moyens de communication avec les chose qui est à côté de la norme, la norme étant ici le morts : naturels (médiumnité, nécromancie) ou ar- consensus scientifique d'une époque. Un phénomène est tificiels (la transcommunication instrumentale telle qualifié de paranormal lorsqu'il ne semble pas pouvoir que les voix électroniques); être expliqué par les lois naturelles connues, laissant ain- si le champ libre à de nouvelles recherches empiriques, à • Les apparitions de l'au-delà (fantômes, revenants, des interprétations, à des suppositions et à l'imaginaire. ectoplasmes, poltergeists, etc.) ; Les initiateurs de la parapsychologie se sont donné comme objectif d'étudier d'une manière scientifique • la cryptozoologie (qui étudie l'existence d'espèce in- ce qu'ils considèrent comme des perceptions extra- connues) : classification assez injuste, car l'objet de sensorielles et de la psychokinèse. Malgré l'existence de la cryptozoologie est moins de cultiver les mythes laboratoires de parapsychologie dans certaines universi- que de chercher s’il y a ou non une espèce animale tés, notamment en Grande-Bretagne, le paranormal est inconnue réelle derrière une légende ; généralement considéré comme un sujet d'étude peu sé- rieux. Il est en revanche parfois associé a des activités • Le phénomène ovni et ses dérivés (cercle de culture). -
Biosignatures Search in Habitable Planets
galaxies Review Biosignatures Search in Habitable Planets Riccardo Claudi 1,* and Eleonora Alei 1,2 1 INAF-Astronomical Observatory of Padova, Vicolo Osservatorio, 5, 35122 Padova, Italy 2 Physics and Astronomy Department, Padova University, 35131 Padova, Italy * Correspondence: [email protected] Received: 2 August 2019; Accepted: 25 September 2019; Published: 29 September 2019 Abstract: The search for life has had a new enthusiastic restart in the last two decades thanks to the large number of new worlds discovered. The about 4100 exoplanets found so far, show a large diversity of planets, from hot giants to rocky planets orbiting small and cold stars. Most of them are very different from those of the Solar System and one of the striking case is that of the super-Earths, rocky planets with masses ranging between 1 and 10 M⊕ with dimensions up to twice those of Earth. In the right environment, these planets could be the cradle of alien life that could modify the chemical composition of their atmospheres. So, the search for life signatures requires as the first step the knowledge of planet atmospheres, the main objective of future exoplanetary space explorations. Indeed, the quest for the determination of the chemical composition of those planetary atmospheres rises also more general interest than that given by the mere directory of the atmospheric compounds. It opens out to the more general speculation on what such detection might tell us about the presence of life on those planets. As, for now, we have only one example of life in the universe, we are bound to study terrestrial organisms to assess possibilities of life on other planets and guide our search for possible extinct or extant life on other planetary bodies. -
University of Groningen Evaluating Galactic Habitability Using High
University of Groningen Evaluating galactic habitability using high-resolution cosmological simulations of galaxy formation Forgan, Duncan; Dayal, Pratika; Cockell, Charles; Libeskind, Noam Published in: International Journal of Astrobiology DOI: 10.1017/S1473550415000518 IMPORTANT NOTE: You are advised to consult the publisher's version (publisher's PDF) if you wish to cite from it. Please check the document version below. Document Version Final author's version (accepted by publisher, after peer review) Publication date: 2017 Link to publication in University of Groningen/UMCG research database Citation for published version (APA): Forgan, D., Dayal, P., Cockell, C., & Libeskind, N. (2017). Evaluating galactic habitability using high- resolution cosmological simulations of galaxy formation. International Journal of Astrobiology, 16(1), 60–73. https://doi.org/10.1017/S1473550415000518 Copyright Other than for strictly personal use, it is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license (like Creative Commons). The publication may also be distributed here under the terms of Article 25fa of the Dutch Copyright Act, indicated by the “Taverne” license. More information can be found on the University of Groningen website: https://www.rug.nl/library/open-access/self-archiving-pure/taverne- amendment. Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Downloaded from the University of Groningen/UMCG research database (Pure): http://www.rug.nl/research/portal. -
Comparative Habitability of Transiting Exoplanets
Draft version October 1, 2015 A Preprint typeset using LTEX style emulateapj v. 04/17/13 COMPARATIVE HABITABILITY OF TRANSITING EXOPLANETS Rory Barnes1,2,3, Victoria S. Meadows1,2, Nicole Evans1,2 Draft version October 1, 2015 ABSTRACT Exoplanet habitability is traditionally assessed by comparing a planet’s semi-major axis to the location of its host star’s “habitable zone,” the shell around a star for which Earth-like planets can possess liquid surface water. The Kepler space telescope has discovered numerous planet candidates near the habitable zone, and many more are expected from missions such as K2, TESS and PLATO. These candidates often require significant follow-up observations for validation, so prioritizing planets for habitability from transit data has become an important aspect of the search for life in the universe. We propose a method to compare transiting planets for their potential to support life based on transit data, stellar properties and previously reported limits on planetary emitted flux. For a planet in radiative equilibrium, the emitted flux increases with eccentricity, but decreases with albedo. As these parameters are often unconstrained, there is an “eccentricity-albedo degeneracy” for the habitability of transiting exoplanets. Our method mitigates this degeneracy, includes a penalty for large-radius planets, uses terrestrial mass-radius relationships, and, when available, constraints on eccentricity to compute a number we call the “habitability index for transiting exoplanets” that represents the relative probability that an exoplanet could support liquid surface water. We calculate it for Kepler Objects of Interest and find that planets that receive between 60–90% of the Earth’s incident radiation, assuming circular orbits, are most likely to be habitable. -
PLANETARY CANDIDATES OBSERVED by Kepler. VIII. a FULLY AUTOMATED CATALOG with MEASURED COMPLETENESS and RELIABILITY BASED on DATA RELEASE 25
Draft version October 13, 2017 Typeset using LATEX twocolumn style in AASTeX61 PLANETARY CANDIDATES OBSERVED BY Kepler. VIII. A FULLY AUTOMATED CATALOG WITH MEASURED COMPLETENESS AND RELIABILITY BASED ON DATA RELEASE 25 Susan E. Thompson,1, 2, 3, ∗ Jeffrey L. Coughlin,2, 1 Kelsey Hoffman,1 Fergal Mullally,1, 2, 4 Jessie L. Christiansen,5 Christopher J. Burke,2, 1, 6 Steve Bryson,2 Natalie Batalha,2 Michael R. Haas,2, y Joseph Catanzarite,1, 2 Jason F. Rowe,7 Geert Barentsen,8 Douglas A. Caldwell,1, 2 Bruce D. Clarke,1, 2 Jon M. Jenkins,2 Jie Li,1 David W. Latham,9 Jack J. Lissauer,2 Savita Mathur,10 Robert L. Morris,1, 2 Shawn E. Seader,11 Jeffrey C. Smith,1, 2 Todd C. Klaus,2 Joseph D. Twicken,1, 2 Jeffrey E. Van Cleve,1 Bill Wohler,1, 2 Rachel Akeson,5 David R. Ciardi,5 William D. Cochran,12 Christopher E. Henze,2 Steve B. Howell,2 Daniel Huber,13, 14, 1, 15 Andrej Prša,16 Solange V. Ramírez,5 Timothy D. Morton,17 Thomas Barclay,18 Jennifer R. Campbell,2, 19 William J. Chaplin,20, 15 David Charbonneau,9 Jørgen Christensen-Dalsgaard,15 Jessie L. Dotson,2 Laurance Doyle,21, 1 Edward W. Dunham,22 Andrea K. Dupree,9 Eric B. Ford,23, 24, 25, 26 John C. Geary,9 Forrest R. Girouard,27, 2 Howard Isaacson,28 Hans Kjeldsen,15 Elisa V. Quintana,18 Darin Ragozzine,29 Avi Shporer,30 Victor Silva Aguirre,15 Jason H. Steffen,31 Martin Still,8 Peter Tenenbaum,1, 2 William F. -
Recipe for a Habitable Planet
Recipe for a Habitable Planet Aomawa Shields Clare Boothe Luce Associate Professor Shields Center for Exoplanet Climate and Interdisciplinary Education (SCECIE) University of California, Irvine ASU School of Earth and Space Exploration (SESE) December 2, 2020 A moment to pause… Leading effectively during COVID-19 • Employees Need Trust and Compassion: Be Present, Even When You're Distant • Employees Need Stability: Prioritize Wellbeing Amid Disruption • Employees Need Hope: Anchor to Your "True North" From “3 strategies for leading effectively during COVID-19” (https://www.gallup.com/workplace/306503/strategies-leading-effectively-amid-covid.aspx) Hobbies: reading movies, shows knitting mixed media/collage violin tea yoga good restaurants spa days the beach hiking smelling flowers hanging with family BINGO Ill. Niklas Elmehed. Ill. Niklas Elmehed. © Nobel Media. © Nobel Media. RadialVelocity (m/s) Nobel Prize in Physics 2019 Mayor & Queloz 1995 https://exoplanets.nasa.gov/ As of December 2, 2020 Aomawa Shields Recipe for a Habitable World Credit: NASA NNASA’sASA’s KKeplerepler MMissionission TESS Transiting Exoplanet Survey Satellite Credit: NASA-JPL/Caltech Proxima Centauri b Credit: ESO/M. Kornmesser LHS 1140b Credit: ESO TOI 700d Credit: NASA TESS planets in the Earth-sized regime Credit: NASA’s Goddard Space Flight Center Which ones do we follow up on? 20 The Habitable Zone (Kasting et al. 1993, Kopparapu et al. 2013) ) Runaway greenhouse Maximum CO2 greenhouse Stellar Mass (M Mass Stellar Distance from Star (AU) Snowball Earth Many factors can affect planetary habitability Aomawa Shields Recipe for a Habitable World Liquid water Aomawa Shields Recipe for a Habitable World Isotopic Birth Tides Orbit Abundance Environ. -
Goldilocks Planet)
Anthropomorphic (formed for man) Is the universe the way it is because it was designed with man in mind? • The widely accepted principle of mediocrity (also called the Copernican principle), is advocated by Carl Sagan and Frank Drake, among others. • The principle of mediocrity concludes that the Earth is a typical rocky planet in a typical planetary system, located in a non-exceptional region of a common spiral galaxy. Hence it is probable that the universe teems with complex life. 1 RARE EARTH HYPOTHESIS (GOLDILOCKS PLANET) • The term "Rare Earth" originates from Rare Earth: Why Complex Life Is Uncommon in the Universe (2000), a book by Peter Ward, a geologist and paleontologist, and Donald Brownlee, an astronomer and astrobiologist. • In planetary astronomy and astrobiology, the Rare Earth hypothesis argues that the emergence of complex multicellular life on earth, required an improbable combination of astrophysical and geological events and circumstances. The hypothesis argues that complex extraterrestrial life requires an earth like planet with similar circumstance and that few if any such planets exist. 2 Ward and Brownlee argue to the contrary: planets, planetary systems, and galactic regions that are as friendly to complex life as are the Earth, the Solar System, and our region of the Milky Way are very rare. 3 • Early modern science allegedly put an end to the anthropomorphic conceit by showing, not only was earth not the center of the universe, but there was nothing special about the earth. “Copernican Principle” • Science may now be discovering that we and our planet are far more special than we could have known.