Astronomy 101 -- Worksheet #5THE SOLAR SYSTEM and PLANET EARTH1) The solar system is made up of one star,the _____________, 9 _____________, and many______________, _________________, _______________, and ______________.2) One major difference between a star and a planet is that stars ____________ light, while planets_____________ light.3) The 9planets, in order of increasing average distance from the Sun, are _____________,_____________, _____________, _____________, _____________, _____________, _____________,_____________, and _____________.4) The outer 3 planets are not visible to the naked eye, and were not discovered until after the inventionof the telescope. These planets are _____________, _____________, and _____________.5) The planets all orbit the Sun in the plane known as the _____________. This orbital motion is alsocalled _____________. The plane of Pluto’sorbit exhibits the largest _____________ of all the planetaryorbits relative tothe ecliptic, with an inclination of about 17°.6) The Sun contains over__________% of the mass of the solar system. Most of the remaining__________% is found in _____________.7) The overall shape of the solar system is ____________________. This is known because the planetsare always seen to be close to the _____________ in the sky.8) The planets all _____________ around the the Sun, and most planets _____________ on their axes, inthe same direction -- counterclockwise as seen from the North.9) The orbits of the planets, comets, and asteroids around the Sun are ellipses with the Sun at one focus(according to _____________ _____________ Law). However, the planetary orbits are ellipses whichare nearly _____________, while cometary orbits are ellipses which are highly _____________.10) The radius of the Sun is about _____________ times larger than that of the Earth, while the radius ofthe Earth is about _____________ times larger than that of the Moon. Since the volume of a sphere de-pends on the cube of the radius, the volume of the Sun is about _____________ times larger than that ofthe Earth, while the volume of the Earth is about _____________ times larger than that of the Moon.11) The distance from the Earth to the Sun is about 150,000,000 km or 93,000,000 miles. This distanceis known as the ____________________.12) The distances of the planets from the Sun can all be measured relative tothe ____________________using trigonometry.The Astronomical Unit can then be measured relative tothe____________________.13) One wayofclassifying the planets is in terms of their distance from the Sun. The planets which arecloser to the Sun than Earth are known as _____________, while those which are farther from the Sunthan Earth are known as _____________. The _____________ planets can neverbeseen at midnight,while the _____________ planets can be seen during the middle of the day or night.14) When planets are classified in terms of their physical properties, the major categories are the Earth-like, or _______________ planets, and the Jupiter-like, or _______________ planets. The-2-_______________ planets are smaller with high densities (likerock), while the _______________ planetsare larger with lowdensities (likewater).15) The force which binds the planets to the Sun in the solar system is known as _______________. Thestrength of the force of _____________ between the Sun and planet X depends on the _____________ ofthe Sun, the _____________ of planet X, and the _____________ of the distance between them. If themass of the planet or the Sun increases, the force will _____________ in proportion, and if the distancebetween the planet and the Sun increases the force will _____________ as the square of the distance be-tween them.16) Suppose you discoveranew planet which is found to be 6 A.U. from the Sun with the same mass asthat of the Earth. Relative tothe force of _____________ between the Sun and the Earth, the force be-tween the Sun and the newplanet will be _____________ times _____________ (stronger/weaker).17) Astronomers use measurements of the orbits of moons, planets, stars, and galaxies to determine the_____________ of objects in the Universe. This procedure is based on Kepler’s_____________ Law.18) The density of an object is defined as the _____________ divided by the _____________. Afamiliardensity standard is water -- since 1 gram (1 g) of water is contained in a volume of 1 cubic centimeter (1cm3), water has a density of 1 g/cm3.Rock has a higher density,between 3 and 5 g/cm3,and oil has alower density than water (so it floats on water).19) Planet Earth is the largest of the _____________ planets. The atmosphere which surrounds our plan-et serves both to _______________________ and ______________________ as well as provide oxygenfor us to breathe.20) The Earth’satmosphere is composed of 77% _____________, 21% _____________, and traces ofother gases (including argon, water vapor,carbon dioxide and ozone).21) The trapping of heat near the surface of a planet by molecules (such as CO2)inthe atmosphere isknown as the _______________ effect. This effect is very significant on the planet _____________, andis becoming more so on the Earth as we burn more fossil fuels to produce energy.22) The Earth’sinterior is probed by seismic wav eswhich pass through our planet after theyare pro-duced in _____________. The general features of the Earth’sinterior include the _____________, the_____________, and the _____________. The outer _____________ is liquid, while the inner_____________ is solid.23) The Earth behaveslikeamagnet, with a magnetic field which is generated in the____________________. It is because of the Earth’smagnetic field that a compass points North (to mag-netic North, that is).24) The surface of the Earth changes slowly overtime, due to the process known as____________________. The surface of the Earth appears to be made of ∼10 large _____________which float on the mantle. As these _____________ collide, separate, or pass by each other,weexperi-ence ____________________, ____________________, ___________________,