Exomoon Habitability and Tidal Evolution in Low-Mass Star Systems
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
High Precision Photometry of Transiting Exoplanets
McNair Scholars Research Journal Volume 3 Article 3 2016 High Precision Photometry of Transiting Exoplanets Maurice Wilson Embry-Riddle Aeronautical University and Harvard-Smithsonian Center for Astrophysics Jason Eastman Harvard-Smithsonian Center for Astrophysics John Johnson Harvard-Smithsonian Center for Astrophysics Follow this and additional works at: https://commons.erau.edu/mcnair Recommended Citation Wilson, Maurice; Eastman, Jason; and Johnson, John (2016) "High Precision Photometry of Transiting Exoplanets," McNair Scholars Research Journal: Vol. 3 , Article 3. Available at: https://commons.erau.edu/mcnair/vol3/iss1/3 This Article is brought to you for free and open access by the Journals at Scholarly Commons. It has been accepted for inclusion in McNair Scholars Research Journal by an authorized administrator of Scholarly Commons. For more information, please contact [email protected]. Wilson et al.: High Precision Photometry of Transiting Exoplanets High Precision Photometry of Transiting Exoplanets Maurice Wilson1,2, Jason Eastman2, and John Johnson2 1Embry-Riddle Aeronautical University 2Harvard-Smithsonian Center for Astrophysics In order to increase the rate of finding, confirming, and characterizing Earth-like exoplanets, the MINiature Exoplanet Radial Velocity Array (MINERVA) was recently built with the purpose of obtaining the spectroscopic and photometric precision necessary for these tasks. Achieving the satisfactory photometric precision is the primary focus of this work. This is done with the four telescopes of MINERVA and the defocusing technique. The satisfactory photometric precision derives from the defocusing technique. The use of MINERVA’s four telescopes benefits the relative photometry that must be conducted. Typically, it is difficult to find satisfactory comparison stars within a telescope’s field of view when the primary target is very bright. -
Lab 7: Gravity and Jupiter's Moons
Lab 7: Gravity and Jupiter's Moons Image of Galileo Spacecraft Gravity is the force that binds all astronomical structures. Clusters of galaxies are gravitationally bound into the largest structures in the Universe, Galactic Superclusters. The galaxies themselves are held together by gravity, as are all of the star systems within them. Our own Solar System is a collection of bodies gravitationally bound to our star, Sol. Cutting edge science requires the use of Einstein's General Theory of Relativity to explain gravity. But the interactions of the bodies in our Solar System were understood long before Einstein's time. In chapter two of Chaisson McMillan's Astronomy Today, you went over Kepler's Laws. These laws of gravity were made to describe the interactions in our Solar System. P2=a3/M Where 'P' is the orbital period in Earth years, the time for the body to make one full orbit. 'a' is the length of the orbit's semi-major axis, for nearly circular orbits the orbital radius. 'M' is the total mass of the system in units of Solar Masses. Jupiter System Montage picture from NASA ID = PIA01481 Jupiter has over 60 moons at the last count, most of which are asteroids and comets captured from Written by Meagan White and Paul Lewis Page 1 the Asteroid Belt. When Galileo viewed Jupiter through his early telescope, he noticed only four moons: Io, Europa, Ganymede, and Callisto. The Jupiter System can be thought of as a miniature Solar System, with Jupiter in place of the Sun, and the Galilean moons like planets. -
The Geology of the Rocky Bodies Inside Enceladus, Europa, Titan, and Ganymede
49th Lunar and Planetary Science Conference 2018 (LPI Contrib. No. 2083) 2905.pdf THE GEOLOGY OF THE ROCKY BODIES INSIDE ENCELADUS, EUROPA, TITAN, AND GANYMEDE. Paul K. Byrne1, Paul V. Regensburger1, Christian Klimczak2, DelWayne R. Bohnenstiehl1, Steven A. Hauck, II3, Andrew J. Dombard4, and Douglas J. Hemingway5, 1Planetary Research Group, Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695, USA ([email protected]), 2Department of Geology, University of Georgia, Athens, GA 30602, USA, 3Department of Earth, Environmental, and Planetary Sciences, Case Western Reserve University, Cleveland, OH 44106, USA, 4Department of Earth and Environmental Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA, 5Department of Earth & Planetary Science, University of California Berkeley, Berkeley, CA 94720, USA. Introduction: The icy satellites of Jupiter and horizontal stresses, respectively, Pp is pore fluid Saturn have been the subjects of substantial geological pressure (found from (3)), and μ is the coefficient of study. Much of this work has focused on their outer friction [12]. Finally, because equations (4) and (5) shells [e.g., 1–3], because that is the part most readily assess failure in the brittle domain, we also considered amenable to analysis. Yet many of these satellites ductile deformation with the relation n –E/RT feature known or suspected subsurface oceans [e.g., 4– ε̇ = C1σ exp , (6) 6], likely situated atop rocky interiors [e.g., 7], and where ε̇ is strain rate, C1 is a constant, σ is deviatoric several are of considerable astrobiological significance. stress, n is the stress exponent, E is activation energy, R For example, chemical reactions at the rock–water is the universal gas constant, and T is temperature [13]. -
Galileo and the Telescope
Galileo and the Telescope A Discussion of Galileo Galilei and the Beginning of Modern Observational Astronomy ___________________________ Billy Teets, Ph.D. Acting Director and Outreach Astronomer, Vanderbilt University Dyer Observatory Tuesday, October 20, 2020 Image Credit: Giuseppe Bertini General Outline • Telescopes/Galileo’s Telescopes • Observations of the Moon • Observations of Jupiter • Observations of Other Planets • The Milky Way • Sunspots Brief History of the Telescope – Hans Lippershey • Dutch Spectacle Maker • Invention credited to Hans Lippershey (c. 1608 - refracting telescope) • Late 1608 – Dutch gov’t: “ a device by means of which all things at a very great distance can be seen as if they were nearby” • Is said he observed two children playing with lenses • Patent not awarded Image Source: Wikipedia Galileo and the Telescope • Created his own – 3x magnification. • Similar to what was peddled in Europe. • Learned magnification depended on the ratio of lens focal lengths. • Had to learn to grind his own lenses. Image Source: Britannica.com Image Source: Wikipedia Refracting Telescopes Bend Light Refracting Telescopes Chromatic Aberration Chromatic aberration limits ability to distinguish details Dealing with Chromatic Aberration - Stop Down Aperture Galileo used cardboard rings to limit aperture – Results were dimmer views but less chromatic aberration Galileo and the Telescope • Created his own (3x, 8-9x, 20x, etc.) • Noted by many for its military advantages August 1609 Galileo and the Telescope • First observed the -
Astronomy 330 HW 2 Presentations Outline
Astronomy 330 HW 2 •! Stanley Swat This class (Lecture 12): http://www.ufohowto.com/ Life in the Solar System •! Lucas Guthrie Next Class: http://www.crystalinks.com/abduction.html Life in the Solar System HW 5 is due Wednesday Music: We Are All Made of Stars– Moby Presentations Outline •! Daniel Borup •! Life on Venus? Futurama •! Life on Mars? Life in the Solar System? Earth – Venus comparison •! We want to examine in more detail the backyard of humans. •! What we find may change our estimates of ne. Radius 0.95 Earth Surface gravity 0.91 Earth Venus is the hottest Mass 0.81 Earth planet, the closest in Distance from Sun 0.72 AU size to Earth, the closest Average Temp 475 C in distance to Earth, and Year 224.7 Earth days the planet with the Length of Day 116.8 Earth days longest day. Atmosphere 96% CO2 What We Used to Think Turns Out that Venus is Hell Venus must be hotter, as it is closer the Sun, but the cloud •! The surface is hot enough to melt lead cover must reflect back a large amount of the heat. •! There is a runaway greenhouse effect •! There is almost no water In 1918, a Swedish chemist and Nobel laureate concluded: •! There is sulfuric acid rain •! Everything on Venus is dripping wet. •! Most of the surface is no doubt covered with swamps. •! Not a place to visit for Spring Break. •! The constantly uniform climatic conditions result in an entire absence of adaptation to changing exterior conditions. •! Only low forms of life are therefore represented, mostly no doubt, belonging to the vegetable kingdom; and the organisms are nearly of the same kind all over the planet. -
Exomoon Habitability Constrained by Illumination and Tidal Heating
submitted to Astrobiology: April 6, 2012 accepted by Astrobiology: September 8, 2012 published in Astrobiology: January 24, 2013 this updated draft: October 30, 2013 doi:10.1089/ast.2012.0859 Exomoon habitability constrained by illumination and tidal heating René HellerI , Rory BarnesII,III I Leibniz-Institute for Astrophysics Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany, [email protected] II Astronomy Department, University of Washington, Box 951580, Seattle, WA 98195, [email protected] III NASA Astrobiology Institute – Virtual Planetary Laboratory Lead Team, USA Abstract The detection of moons orbiting extrasolar planets (“exomoons”) has now become feasible. Once they are discovered in the circumstellar habitable zone, questions about their habitability will emerge. Exomoons are likely to be tidally locked to their planet and hence experience days much shorter than their orbital period around the star and have seasons, all of which works in favor of habitability. These satellites can receive more illumination per area than their host planets, as the planet reflects stellar light and emits thermal photons. On the contrary, eclipses can significantly alter local climates on exomoons by reducing stellar illumination. In addition to radiative heating, tidal heating can be very large on exomoons, possibly even large enough for sterilization. We identify combinations of physical and orbital parameters for which radiative and tidal heating are strong enough to trigger a runaway greenhouse. By analogy with the circumstellar habitable zone, these constraints define a circumplanetary “habitable edge”. We apply our model to hypothetical moons around the recently discovered exoplanet Kepler-22b and the giant planet candidate KOI211.01 and describe, for the first time, the orbits of habitable exomoons. -
Where Are the Distant Worlds? Star Maps
W here Are the Distant Worlds? Star Maps Abo ut the Activity Whe re are the distant worlds in the night sky? Use a star map to find constellations and to identify stars with extrasolar planets. (Northern Hemisphere only, naked eye) Topics Covered • How to find Constellations • Where we have found planets around other stars Participants Adults, teens, families with children 8 years and up If a school/youth group, 10 years and older 1 to 4 participants per map Materials Needed Location and Timing • Current month's Star Map for the Use this activity at a star party on a public (included) dark, clear night. Timing depends only • At least one set Planetary on how long you want to observe. Postcards with Key (included) • A small (red) flashlight • (Optional) Print list of Visible Stars with Planets (included) Included in This Packet Page Detailed Activity Description 2 Helpful Hints 4 Background Information 5 Planetary Postcards 7 Key Planetary Postcards 9 Star Maps 20 Visible Stars With Planets 33 © 2008 Astronomical Society of the Pacific www.astrosociety.org Copies for educational purposes are permitted. Additional astronomy activities can be found here: http://nightsky.jpl.nasa.gov Detailed Activity Description Leader’s Role Participants’ Roles (Anticipated) Introduction: To Ask: Who has heard that scientists have found planets around stars other than our own Sun? How many of these stars might you think have been found? Anyone ever see a star that has planets around it? (our own Sun, some may know of other stars) We can’t see the planets around other stars, but we can see the star. -
JUICE Red Book
ESA/SRE(2014)1 September 2014 JUICE JUpiter ICy moons Explorer Exploring the emergence of habitable worlds around gas giants Definition Study Report European Space Agency 1 This page left intentionally blank 2 Mission Description Jupiter Icy Moons Explorer Key science goals The emergence of habitable worlds around gas giants Characterise Ganymede, Europa and Callisto as planetary objects and potential habitats Explore the Jupiter system as an archetype for gas giants Payload Ten instruments Laser Altimeter Radio Science Experiment Ice Penetrating Radar Visible-Infrared Hyperspectral Imaging Spectrometer Ultraviolet Imaging Spectrograph Imaging System Magnetometer Particle Package Submillimetre Wave Instrument Radio and Plasma Wave Instrument Overall mission profile 06/2022 - Launch by Ariane-5 ECA + EVEE Cruise 01/2030 - Jupiter orbit insertion Jupiter tour Transfer to Callisto (11 months) Europa phase: 2 Europa and 3 Callisto flybys (1 month) Jupiter High Latitude Phase: 9 Callisto flybys (9 months) Transfer to Ganymede (11 months) 09/2032 – Ganymede orbit insertion Ganymede tour Elliptical and high altitude circular phases (5 months) Low altitude (500 km) circular orbit (4 months) 06/2033 – End of nominal mission Spacecraft 3-axis stabilised Power: solar panels: ~900 W HGA: ~3 m, body fixed X and Ka bands Downlink ≥ 1.4 Gbit/day High Δv capability (2700 m/s) Radiation tolerance: 50 krad at equipment level Dry mass: ~1800 kg Ground TM stations ESTRAC network Key mission drivers Radiation tolerance and technology Power budget and solar arrays challenges Mass budget Responsibilities ESA: manufacturing, launch, operations of the spacecraft and data archiving PI Teams: science payload provision, operations, and data analysis 3 Foreword The JUICE (JUpiter ICy moon Explorer) mission, selected by ESA in May 2012 to be the first large mission within the Cosmic Vision Program 2015–2025, will provide the most comprehensive exploration to date of the Jovian system in all its complexity, with particular emphasis on Ganymede as a planetary body and potential habitat. -