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29_worlds_unnumbered..
29_worlds_unnumbered..

... mass, period of wobble tells length of planets “year”. From length of “year” we can determine radius of orbit (how far it is from the star). We don’t know what the planet looks like, all we know are its mass and orbit. ...
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... • Why are there rings? • Probably a moon that got too close! ...
HERE - physicsisphun.org
HERE - physicsisphun.org

... Temperature and color of stars • Hotter objects glow with light of higher intensity at shorter wavelength. This light is more toward the blue or violet end of the visible light spectrum. • Cooler objects glow with light intensity at the longer wavelengths or more toward the red end of the spectrum. ...
PPT - El Camino College
PPT - El Camino College

... formation model • Motions – counterclockwise, almost circles, and in same disk (flat) • Two types of planets: – Terrestrial – small, rocky & metallic, near the Sun & close together – Jovian – large, gaseous, far away & far apart ...
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... an object must: 1) orbit a star; 2) be large enough for its own gravity to make it round; and 3) must have cleared out most other objects from its orbital path. Pluto satisfies the first two criteria, but not the third. Pluto's orbit is inclined (tilted) 17 degrees from the plane of the Earth's orbi ...
I. What is an Exoplanet?
I. What is an Exoplanet?

... orbits around their stars will undergo reflected light variations.  This is because, like our Moon, they also go through phases from full to new and back again.  Since telescopes cannot resolve the planet from the star, they see only the combined light.  The brightness of the host star will seem ...
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AST 1002 Fall 2014 Midterm Exam Version 1
AST 1002 Fall 2014 Midterm Exam Version 1

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... asteroid belt, comets, meteors, and others. The sun is the center of our solar system; the planets, their moons, the asteroids, comets, and other rocks and gas all orbit the sun. The nine planets that orbit the sun are (in order from the sun): Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Ne ...
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FAR, FAR AWAY - Museum of Science and Industry
FAR, FAR AWAY - Museum of Science and Industry

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... Foucault pendulum: a freely swinging pendulum whose path appears to change over time in a predictable manner; provides evidence of Earth’s rotation. Geocentric Model: any celestial model that has Earth at its center. Heliocentric Model: any celestial model that has Sun at its center. Jovian planets: ...
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... hydrogen and helium. Their thick outer layers are gases and have liquid interiors •All of the outer planets have lots of moons, as well as planetary rings made of dust and other particles ...
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Exoplanets - An ESO/OPTICON/IAU summer school on modern

... (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 neighbourhood around its orbit." IAU, Resolution B5 "Extrasolar planet is: an object that has a mass between that of Pluto and the deu ...
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The Origin of the Solar System Chapter 8:
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... Remains of the protostellar nebula were cleared away by: • Radiation pressure of the sun • Sweeping-up of space debris by planets ...
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HOMEWORK 5 SOLUTIONS CHAPTER 9 4.A A red giant star will

... the Earth’s orbit will not change. Since the Sun is so far away, it appears to the Earth to be a point source. The black hole will also appear to be a point source so the orbit will not change. CHAPTER 11 1.C The halo is home to old, metal-poor stars. Globular clusters contain some of the oldest sta ...
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Definition of planet



The definition of planet, since the word was coined by the ancient Greeks, has included within its scope a wide range of celestial bodies. Greek astronomers employed the term asteres planetai (ἀστέρες πλανῆται), ""wandering stars"", for star-like objects which apparently moved over the sky. Over the millennia, the term has included a variety of different objects, from the Sun and the Moon to satellites and asteroids.By the end of the 19th century the word planet, though it had yet to be defined, had become a working term applied only to a small set of objects in the Solar System. After 1992, however, astronomers began to discover many additional objects beyond the orbit of Neptune, as well as hundreds of objects orbiting other stars. These discoveries not only increased the number of potential planets, but also expanded their variety and peculiarity. Some were nearly large enough to be stars, while others were smaller than Earth's moon. These discoveries challenged long-perceived notions of what a planet could be.The issue of a clear definition for planet came to a head in 2005 with the discovery of the trans-Neptunian object Eris, a body more massive than the smallest then-accepted planet, Pluto. In its 2006 response, the International Astronomical Union (IAU), recognised by astronomers as the world body responsible for resolving issues of nomenclature, released its decision on the matter. This definition, which applies only to the Solar System, states that a planet is a body that orbits the Sun, is massive enough for its own gravity to make it round, and has ""cleared its neighbourhood"" of smaller objects around its orbit. Under this new definition, Pluto and the other trans-Neptunian objects do not qualify as planets. The IAU's decision has not resolved all controversies, and while many scientists have accepted the definition, some in the astronomical community have rejected it outright.
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