ASTR-101 Section 004 Lecture 7 Comparative Planetology: The

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ASTR-101 Section 004 Lecture 7 Comparative Planetology: The

ASTR-101 Section 004 Lecture 8 Introduction to the Solar System John T. McGraw, Professor Danielle - Theater Operations Test 1 Results • Max Score 76 out of 85. • Curve set at 78: 3 A’s 7 B’s 8 C’s 4 D’s 1 F’ • Did I score your test correctly? • Do you think a question it is unfair or has the wrong answer? 64% Earthlike and Jupiter-like The Terrestrial and Jovian Planets • The four inner planets are called terrestrial planets • Relatively small (with diameters of 5000 to 13,000 km) • High average densities (4000 to 5500 kg/m3) • Composed primarily of rocky materials • The four giant outer planets are called Jovian planets • Large diameters (50,000 to 143,000 km) • Low average densities (700 to 1700 kg/m3) • Composed primarily of hydrogen and helium gas. Pluto •Pluto is a special case • Smaller than any of the terrestrial planets • Intermediate average density of about 1900 kg/m3 • Density suggests it is composed of a mixture of ice and rock • Many Pluto-like Kuiper Belt Objects (KBOs) are now known • Pluto was discovered by Clyde Tombaugh, long-time professor at NMSU. By NM State Law, Pluto remains a “planet!” Definition of a planet • The definition of planet set in August 2006 by the International Astronomical Union (IAU) states that, in the Solar System, a planet is a celestial body which: 1. is in orbit around the Sun, 2. has sufficient mass to assume hydrostatic equilibrium (a nearly round shape), and 3. has "cleared the neighborhood" around its orbit. Dwarf Planets • A dwarf planet is a planetary-mass object that is neither a planet nor a natural satellite. • Orbit of a star, is massive enough for its gravity to crush it into a hydrostatically equilibrious shape (usually a spheroid), but has not cleared the neighborhood of other material around its orbit. Ceres as seen from the Dawn Pluto as viewed by New Eris and its moon Dysnomia viewed spacecraft. It is the only dwarf Horizons space probe by the Hubble Space Telescope. planet in the asteroid belt. on July 13, 2015. Makemake and its moon viewed by the Hubble Space Telescope. Small chunks of rock and ice orbiting the Sun • Asteroids are small, rocky objects, while comets and Kuiper belt objects are made of dirty ice • All are remnants left over from the formation of the planets • The Kuiper belt extends far beyond the orbit of Pluto • Pluto can be thought of as the first member of the Kuiper belt L3 L5 L4 ~ 5 AU Seven large satellites are almost as big as the terrestrial planets The abundances of the chemical elements .

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Apparent Size of Celestial Objects
NATURE [April 7, 1870 daher wie schon fri.jher die Vor!esungen Uber die Warme, so of rectifying, we assume. :J'o me the Moon at an altit11de of auch jetzt die vorliegenden Vortrage Uber d~n Sc:hall unter 1~rer 45° is about (> i!lches in diameter ; when near the horizon, she is besonderen Aufsicht iibersetzen lasse~, und die :On1ckbogen e1µer about a foot. If I look through a telescope of small ruag11ifyjng genauen Durchsicht unterzogen, dam1t auch die deutsche J3ear power (say IO or 12 diameters), sQ as to leave a fair margin in beitung den englischen Werken ihres Freundes Tyndall nach the field, the Moon is still 6 inches in diameter, though her Form und Inhalt moglichst entsprache.-H. :fIEL!>iHOLTZ, G. visible area has really increased a hundred:fold. WIEDEMANN." . Can we go further than to say, as has often been said, that aH Prof. Tyndall's work, his account of Helmhqltz's Theory of magnitudi; is relative, and that nothing is great or small except Dissonance included, having passed through the hands of Helm by comparison? · · W. R. GROVE, holtz himself, not only without protest or correction, bnt with u5, Harley Street, April 4 the foregoing expression of opinion, it does not seem lihly that any serious dimag'e has been done.] · An After Pirm~. Jl;xperim1mt SUPPOSE in the experiment of an ellipsoid or spheroid, referred Apparent Size of Celestial Qpjecti:; to in my last letter, rolling between two parallel liorizontal ABOUT fifteen years ago I was looking at Venus through a planes, we were to scratch on the rolling body the two equal 40-inch telescope, Venus then being very near the Moon and similar and opposite closed curves (the polhods so-called), traced of a crescent form, the line across the middle or widest part upon it by the successive axes of instantaneou~ solutioll ; and of the crescent being about one-tenth of the planet's diameter.
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Constraints on the Spin Evolution of Young Planetary-Mass Companions Marta L
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Solar System KEY.Pdf
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The Nature of the Giant Exomoon Candidate Kepler-1625 B-I René Heller
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