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AS 101 Module 1 Quiz ReviewOur place in the universe:CERN Is a high-energy, physics research facility near Geneva, Switzerland 150 million km= 1.5 x 108km (in scientific notation we write this as).oThat is also known as 1 AU or astronomical unit The Sun:oSun is a star. It was formed from such a cloud about 5 billion years agooThe Sun is 110 times larger in diameter than the EarthoThe Earth orbits the Sun once a yearoMars is only 1.5 AU from the SunoThe average distance from the Sun to the Earth = 1.5 x 108km = 1 AUoAverage distance from Venus to the Sun = 0.7AUThe orbital radius of our outermost planet, Neptune = 40 AU Surrounding solar system: 2 regions of comets & asteroidsoThese objects are small & generate no visible light of their ownLight from the Sun reaches Earth in 8’but it reaches Neptune in over 4 hoursA light-year (ly): simply the distance light travels in one year.Our closest star is Proxima Centauri (4.2ly from the Earth)Sirius is the brightest star in the constellation Canis Major (The Great Dog) Procyon is the brightest star in the constellation Canis Minor (The Little Dog) The Milky Way Galaxyothe spiral galaxy, one of three major types of galaxies oOne of the oldest galaxiesoits age possibly as old as 13 billion yearsoover 100 billion starsspread over the cosmos about 100,000 ly in diameterOur nearest galactic neighbor: the Andromeda galaxy is about 2.5 million ly away and is headed in our directionOur galaxy is part of a cluster of few dozen galaxies called Local Group.oCluster are group into supercluster
The cosmic calendar- concepts of time:the formation of the universe and its age -> us to believe: it has been about 13.8 billion years since the Big BangCosmic calendar (a concept devised by Carl Sagan who was a well-known astronomer in the latter part of the 1900s).Milky way galaxy is about 13.8 billion years oldoBig Bang occurred = midnight on January 1oMilky Way Galaxy starts to coalesce = late February or early MarchoOur solar system starts being built = mid-AugustoPrimitive life exists on Earth = by the end of Septemberocomplex living structures were formed = mid-December oDinosaurs roamed Earth = December 25 oThe end of the dinosaur era (65 million years ago) =December 30Patterns in the Night SkyOn a clear night: 3,000 individual stars visible to the naked eyeoAll these stars are part of Milky Way GalaxyStar patterns are called constellations; all of them have names and some you will recognize (Orion, Cassiopeia, Canis Major, Taurus, Scorpio, Libra, Pisces).The most prominent night sky objects are our MoonoThe Moon's distance from Earth = 384,000 km (30 times Earth’s diameter)oThe Moon's diameter = 3476 km (1/4 of size of Earth)When we look at a particular pattern, such as the constellation Orion:owe are seeing stars that lie at different distances from Earthothese stars are not in a plane but are spread out in all three dimensionsothese stars are moving in different directionsAs we look at different parts of the sky, we see different patterns. As we look at the sky from different places on Earth, we’ll see other patterns