Physics of Terrestrial Planets and Moons: an Introduction and Overview T Spohn, DLR Institut Fu¨R Planetenforschung, Berlin, Germany
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Demoting Pluto Presentation
WWhhaatt HHaappppeenneedd ttoo PPlluuttoo??!!!! Scale in the Solar System, New Discoveries, and the Nature of Science Mary L. Urquhart, Ph.D. Department of Science/Mathematics Education Marc Hairston, Ph.D. William B. Hanson Center for Space Sciences FFrroomm NNiinnee ttoo EEiigghhtt?? On August 24th Pluto was reclassified by the International Astronomical Union (IAU) as a “dwarf planet”. So what happens to “My Very Educated Mother Just Served Us Nine Pizzas”? OOffifficciiaall IAIAUU DDeefifinniittiioonn A planet: (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighborhood around its orbit. A dwarf planet must satisfy only the first two criteria. WWhhaatt iiss SScciieennccee?? National Science Education Standards (National Research Council, 1996) “…science reflects its history and is an ongoing, changing enterprise.” BBeeyyoonndd MMnneemmoonniiccss Science is “ not a collection of facts but an ongoing process, with continual revisions and refinements of concepts necessary in order to arrive at the best current views of the Universe.” - American Astronomical Society AA BBiitt ooff HHiiststoorryy • How have planets been historically defined? • Has a planet ever been demoted before? Planet (from Greek “planetes” meaning wanderer) This was the first definition of “planet” planet Latin English Spanish Italian French Sun Solis Sunday domingo domenica dimanche Moon Lunae Monday lunes lunedì lundi Mars Martis -
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. -
Initiation of Plate Tectonics in the Hadean: Eclogitization Triggered by the ABEL Bombardment
Accepted Manuscript Initiation of plate tectonics in the Hadean: Eclogitization triggered by the ABEL Bombardment S. Maruyama, M. Santosh, S. Azuma PII: S1674-9871(16)30207-9 DOI: 10.1016/j.gsf.2016.11.009 Reference: GSF 514 To appear in: Geoscience Frontiers Received Date: 9 May 2016 Revised Date: 13 November 2016 Accepted Date: 25 November 2016 Please cite this article as: Maruyama, S., Santosh, M., Azuma, S., Initiation of plate tectonics in the Hadean: Eclogitization triggered by the ABEL Bombardment, Geoscience Frontiers (2017), doi: 10.1016/ j.gsf.2016.11.009. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ACCEPTED MANUSCRIPT MANUSCRIPT ACCEPTED P a g e ‐|‐1111‐‐‐‐ ACCEPTED MANUSCRIPT ‐ 1‐ Initiation of plate tectonics in the Hadean: 2‐ Eclogitization triggered by the ABEL 3‐ Bombardment 4‐ 5‐ S. Maruyama a,b,*, M. Santosh c,d,e , S. Azuma a 6‐ a Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1, 7‐ Ookayama-Meguro-ku, Tokyo 152-8550, Japan 8‐ b Institute for Study of the Earth’s Interior, Okayama University, 827 Yamada, 9‐ Misasa, Tottori 682-0193, Japan 10‐ c Centre for Tectonics, Resources and Exploration, Department of Earth 11‐ Sciences, University of Adelaide, SA 5005, Australia 12‐ d School of Earth Sciences and Resources, China University of Geosciences 13‐ Beijing, 29 Xueyuan Road, Beijing 100083, China 14‐ e Faculty of Science, Kochi University, KochiMANUSCRIPT 780-8520, Japan 15‐ *Corresponding author. -
A Deep Search for Additional Satellites Around the Dwarf Planet
Search for Additional Satellites around Haumea A Preprint typeset using LTEX style emulateapj v. 01/23/15 A DEEP SEARCH FOR ADDITIONAL SATELLITES AROUND THE DWARF PLANET HAUMEA Luke D. Burkhart1,2, Darin Ragozzine1,3,4, Michael E. Brown5 Search for Additional Satellites around Haumea ABSTRACT Haumea is a dwarf planet with two known satellites, an unusually high spin rate, and a large collisional family, making it one of the most interesting objects in the outer solar system. A fully self-consistent formation scenario responsible for the satellite and family formation is still elusive, but some processes predict the initial formation of many small moons, similar to the small moons recently discovered around Pluto. Deep searches for regular satellites around KBOs are difficult due to observational limitations, but Haumea is one of the few for which sufficient data exist. We analyze Hubble Space Telescope (HST) observations, focusing on a ten-consecutive-orbit sequence obtained in July 2010, to search for new very small satellites. To maximize the search depth, we implement and validate a non-linear shift-and-stack method. No additional satellites of Haumea are found, but by implanting and recovering artificial sources, we characterize our sensitivity. At distances between 10,000 km and 350,000 km from Haumea, satellites with radii as small as 10 km are ruled out, assuming∼ an albedo∼ (p 0.7) similar to Haumea. We also rule out satellites larger∼ than &40 km in most of the Hill sphere using≃ other HST data. This search method rules out objects similar in size to the small moons of Pluto. -
An Impacting Descent Probe for Europa and the Other Galilean Moons of Jupiter
An Impacting Descent Probe for Europa and the other Galilean Moons of Jupiter P. Wurz1,*, D. Lasi1, N. Thomas1, D. Piazza1, A. Galli1, M. Jutzi1, S. Barabash2, M. Wieser2, W. Magnes3, H. Lammer3, U. Auster4, L.I. Gurvits5,6, and W. Hajdas7 1) Physikalisches Institut, University of Bern, Bern, Switzerland, 2) Swedish Institute of Space Physics, Kiruna, Sweden, 3) Space Research Institute, Austrian Academy of Sciences, Graz, Austria, 4) Institut f. Geophysik u. Extraterrestrische Physik, Technische Universität, Braunschweig, Germany, 5) Joint Institute for VLBI ERIC, Dwingelo, The Netherlands, 6) Department of Astrodynamics and Space Missions, Delft University of Technology, The Netherlands 7) Paul Scherrer Institute, Villigen, Switzerland. *) Corresponding author, [email protected], Tel.: +41 31 631 44 26, FAX: +41 31 631 44 05 1 Abstract We present a study of an impacting descent probe that increases the science return of spacecraft orbiting or passing an atmosphere-less planetary bodies of the solar system, such as the Galilean moons of Jupiter. The descent probe is a carry-on small spacecraft (< 100 kg), to be deployed by the mother spacecraft, that brings itself onto a collisional trajectory with the targeted planetary body in a simple manner. A possible science payload includes instruments for surface imaging, characterisation of the neutral exosphere, and magnetic field and plasma measurement near the target body down to very low-altitudes (~1 km), during the probe’s fast (~km/s) descent to the surface until impact. The science goals and the concept of operation are discussed with particular reference to Europa, including options for flying through water plumes and after-impact retrieval of very-low altitude science data. -
Stagnant Lid Tectonics: Perspectives from Silicate Planets, Dwarf Planets, Large Moons, and Large Asteroids
Geoscience Frontiers 9 (2018) 103e119 HOSTED BY Contents lists available at ScienceDirect China University of Geosciences (Beijing) Geoscience Frontiers journal homepage: www.elsevier.com/locate/gsf Research Paper Stagnant lid tectonics: Perspectives from silicate planets, dwarf planets, large moons, and large asteroids Robert J. Stern a,*, Taras Gerya b, Paul J. Tackley b a Geosciences Department, University of Texas at Dallas, Richardson, TX 75083-0688, USA b Department of Earth Sciences, ETH-Zurich, 8092 Zurich, Switzerland article info abstract Article history: To better understand Earth’s present tectonic styleeplate tectonicseand how it may have evolved from Received 7 November 2016 single plate (stagnant lid) tectonics, it is instructive to consider how common it is among similar bodies Received in revised form in the Solar System. Plate tectonics is a style of convection for an active planetoid where lid fragment 22 May 2017 (plate) motions reflect sinking of dense lithosphere in subduction zones, causing upwelling of Accepted 16 June 2017 asthenosphere at divergent plate boundaries and accompanied by focused upwellings, or mantle plumes; Available online 1 July 2017 any other tectonic style is usefully called “stagnant lid” or “fragmented lid”. In 2015 humanity completed a50þ year effort to survey the 30 largest planets, asteroids, satellites, and inner Kuiper Belt objects, Keywords: “ ” Stagnant lid which we informally call planetoids and use especially images of these bodies to infer their tectonic Solar system activity. The four largest planetoids are enveloped in gas and ice (Jupiter, Saturn, Uranus, and Neptune) Plate tectonics and are not considered. The other 26 planetoids range in mass over 5 orders of magnitude and in Planets diameter over 2 orders of magnitude, from massive Earth down to tiny Proteus; these bodies also range Moons widely in density, from 1000 to 5500 kg/m3. -
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. -
Mars Mars Is the Fourth Terrestrial Planet. It Is Smaller in Size Than
Mars Mars is the fourth terrestrial planet. It is smaller in size than Earth and Venus, but larger than Mercury. Of the planets, Mars is the most hospitable to visiting humans, as it has an atmosphere, though it has no oxygen and is very thin. In the early days of the solar system, Mars has had liquid water on its surface, which is proved by the existence of various minerals that require liquid water to form. The current atmosphere of Mars is too thin and cold for liquid water to exist for long periods of times. Still, there is evidence of terrain shaped by flowing liquids, which are probably temporary flows or floods caused by the melting of ice in the ground. Mars has seasons like the Earth, and ice caps at the poles that grow and shrink over the course of the year. They consist of water ice and CO2 ice, the latter varying more with the seasons. One year on Mars is a bit less than two Earth years. Mars has two moons, Phobos and Deimos. They are very small compared to Mars, and are likely to be asteroids captured by Mars's gravity in the distant past. Giant planets and their moons The outer four planets of the solar system are known as the giant planets, because of their large size (compared to the terrestrial planets). The giant planets of our solar system can be further divided into two categories: gas giants (Jupiter and Saturn) and ice giants (Uranus and Neptune). The gas giants consist mainly of hydrogen (up to 90%) and helium, while the ice giants are mostly "ices" such as water and ammonia, with only some 20% of hydrogen. -
CHORUS: Let's Go Meet the Dwarf Planets There Are Five in Our Solar
Meet the Dwarf Planet Lyrics: CHORUS: Let’s go meet the dwarf planets There are five in our solar system Let’s go meet the dwarf planets Now I’ll go ahead and list them I’ll name them again in case you missed one There’s Pluto, Ceres, Eris, Makemake and Haumea They haven’t broken free from all the space debris There’s Pluto, Ceres, Eris, Makemake and Haumea They’re smaller than Earth’s moon and they like to roam free I’m the famous Pluto – as many of you know My orbit’s on a different path in the shape of an oval I used to be planet number 9, But I break the rules; I’m one of a kind I take my time orbiting the sun It’s a long, long trip, but I’m having fun! Five moons keep me company On our epic journey Charon’s the biggest, and then there’s Nix Kerberos, Hydra and the last one’s Styx 248 years we travel out Beyond the other planet’s regular rout We hang out in the Kuiper Belt Where the ice debris will never melt CHORUS My name is Ceres, and I’m closest to the sun They found me in the Asteroid Belt in 1801 I’m the only known dwarf planet between Jupiter and Mars They thought I was an asteroid, but I’m too round and large! I’m Eris the biggest dwarf planet, and the slowest one… It takes me 557 years to travel around the sun I have one moon, Dysnomia, to orbit along with me We go way out past the Kuiper Belt, there’s so much more to see! CHORUS My name is Makemake, and everyone thought I was alone But my tiny moon, MK2, has been with me all along It takes 310 years for us to orbit ‘round the sun But out here in the Kuiper Belt… our adventures just begun Hello my name’s Haumea, I’m not round shaped like my friends I rotate fast, every 4 hours, which stretched out both my ends! Namaka and Hi’iaka are my moons, I have just 2 And we live way out past Neptune in the Kuiper Belt it’s true! CHORUS Now you’ve met the dwarf planets, there are 5 of them it’s true But the Solar System is a great big place, with more exploring left to do Keep watching the skies above us with a telescope you look through Because the next person to discover one… could be me or you… . -
Is Plate Tectonics Needed to Evolve Technological Species on Exoplanets?
Geoscience Frontiers 7 (2016) 573e580 HOSTED BY Contents lists available at ScienceDirect China University of Geosciences (Beijing) Geoscience Frontiers journal homepage: www.elsevier.com/locate/gsf Research paper Is plate tectonics needed to evolve technological species on exoplanets? Robert J. Stern Geoscience Department, University of Texas at Dallas, Richardson, TX 75080, USA article info abstract Article history: As we continue searching for exoplanets, we wonder if life and technological species capable of Received 23 September 2015 communicating with us exists on any of them. As geoscientists, we can also wonder how important is the Received in revised form presence or absence of plate tectonics for the evolution of technological species. This essay considers this 18 November 2015 question, focusing on tectonically active rocky (silicate) planets, like Earth, Venus, and Mars. The Accepted 4 December 2015 development of technological species on Earth provides key insights for understanding evolution on Available online 29 December 2015 exoplanets, including the likely role that plate tectonics may play. An Earth-sized silicate planet is likely Keywords: to experience several tectonic styles over its lifetime, as it cools and its lithosphere thickens, strengthens, Plate tectonics and becomes denser. These include magma ocean, various styles of stagnant lid, and perhaps plate Exoplanets tectonics. Abundant liquid water favors both life and plate tectonics. Ocean is required for early evolution Planetary science of diverse single-celled organisms, then colonies of cells which specialized further to form guts, ap- Intelligent life pendages, and sensory organisms up to the complexity of fish (central nervous system, appendages, eyes). Large expanses of dry land also begin in the ocean, today produced above subduction zones in juvenile arcs and by their coalescence to form continents, although it is not clear that plate tectonics was required to create continental crust on Earth. -
Spectra As Windows Into Exoplanet Atmospheres
SPECIAL FEATURE: PERSPECTIVE PERSPECTIVE SPECIAL FEATURE: Spectra as windows into exoplanet atmospheres Adam S. Burrows1 Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 Edited by Neta A. Bahcall, Princeton University, Princeton, NJ, and approved December 2, 2013 (received for review April 11, 2013) Understanding a planet’s atmosphere is a necessary condition for understanding not only the planet itself, but also its formation, structure, evolution, and habitability. This requirement puts a premium on obtaining spectra and developing credible interpretative tools with which to retrieve vital planetary information. However, for exoplanets, these twin goals are far from being realized. In this paper, I provide a personal perspective on exoplanet theory and remote sensing via photometry and low-resolution spectroscopy. Although not a review in any sense, this paper highlights the limitations in our knowledge of compositions, thermal profiles, and the effects of stellar irradiation, focusing on, but not restricted to, transiting giant planets. I suggest that the true function of the recent past of exoplanet atmospheric research has been not to constrain planet properties for all time, but to train a new generation of scientists who, by rapid trial and error, are fast establishing a solid future foundation for a robust science of exoplanets. planetary science | characterization The study of exoplanets has increased expo- by no means commensurate with the effort exoplanetology, and this expectation is in part nentially since 1995, a trend that in the short expended. true. The solar system has been a great, per- term shows no signs of abating. Astronomers An important aspect of exoplanets that haps necessary, teacher. -
Sha'áłchíní Welcome to Science Class! What If… My Teacher Gets Kicked August 27, 2020 out of Zoom?
April 26, 2021 Yá’át’ééh! sha'áłchíní Welcome to science class! What if… My teacher gets kicked August 27, 2020 out of Zoom? Then.. 1. If you get assigned as the host end the meeting. 2. Everyone immediately log out of Zoom. 3. Re-enter the class in 5 minutes. 4. If you do not get back into the meeting after continuous tries, class is cancelled. 5. Refer to agenda slides from website. In case Mrs. Yazzie loses internet connection: ● someone becomes host ● host monitors class until Mrs. Yazzie returns or four minutes have passed ● after 4 minutes host ends class ● everyone tries to re-enter class ● if Mrs. Yazzie doesn’t return after another 4 minutes, class is ended for the day Sun. Mon. Tues. Wed. Thurs. Fri. Sat. 1 Intervention 2 3 Science Project PTC 4-7PM Check-In 4 5 6 7 8 9 10 No school Intervention Science Project Check-In 11 12 13 14 15 16 17 Intervention Science Project Due 40 points 18 19 20 21 22 23 24 Intervention 25 26 27 28 29 30 Community Forum Last Intervention NO SCHOOL 5:30pm No School Sun. Mon. Tues. Wed. Thurs. Fri. Sat. 25 26 27 28 29 30 1 Community Forum Last Day of Intervention 5:30PM No School 2 3 4 5 6 7 8 Last Day of Science Zoom No School 9 10 11 12 13 14 15 Mother’s No Zoom No Zoom No Zoom Return school laptops Day NWEA- Math NWEA-RDG NWEA-LANG No School 16 17 18 19 20 21 22 ALL WORK DUE No School 23 24 25 26 27 28 29 30 31 Last Day of School 8th Grade Promotion Announcements ● April 28th-Community Forum ● Friday, April 30th-NO SCHOOL ● Thurs., May 27th- 8th Grade Promotion ● Thurs., May 27th - Last Day of School Agenda -Announcements and Calendar -Student Objective & Essential Question -Intro to Vocabulary -Dwarf Planets -Kahoot! On a scale from 1-10 with 10 being excellent, how was your weekend? UPDATE! ● INGENUITY-2nd Flight Success! ● Perseverance makes oxygen! Student Objective Day 1, Monday: I can describe the relationship of objects in the solar system.