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StuDocu is not sponsored or endorsed by any college or universityAS 101 Module 1 Quiz ReviewAstronomy I Our Place in the Cosmos (Wilfrid Laurier University)StuDocu is not sponsored or endorsed by any college or universityAS 101 Module 1 Quiz ReviewAstronomy I Our Place in the Cosmos (Wilfrid Laurier University)Downloaded by Gong Sil Tae ([email protected])lOMoARcPSD|4381654
AS 101 Module 1 Quiz ReviewOur place in the universeCERN Is a high-energy, physics research facility near Geneva, Switzerland150 million km= In scientific notation we write this as 1.5 x 108km.That is also known as 1 AU or astronomical unit ^The average distance from the Sun to the Earth, about 1.5 x 108km, is defined tobe 1 AUThe orbital radius of our outermost planet, Neptune, is about 40 AUA light-year is simply the distance light travels in one year.Our closest star is Proxima CentauriSirius 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 Galaxy. This spiral galaxy, one of three major types of galaxies shows a swirling mass of over 100 billion stars spread over the cosmos about 100,000 ly in diameter.Our nearest galactic neighbour, the Andromeda galaxy is about 2.5 million ly away and is headed in our directionThe cosmic calendar- concepts of time Our current understanding of the formation of the universe and its age leads us to believe that it has been about 13.8 billion years since the Big Bang,cosmic 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 old Patterns in the Night SkyLooking up at the sky reveals up to 3,000 individual stars visible to the naked eye 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 MoonThe Moon's distance from Earth is about 384,000 kmThe Moon's diameter is 3476 kmWhen we look at a particular pattern, such as the constellation Orion, we are seeing stars that lie at different distances from Earth; these stars are not in a plane but are spread out in all three dimensions and, furthermore, these stars aremoving in different directions.PrecessionDownloaded by Gong Sil Tae ([email protected])lOMoARcPSD|4381654
The Earth's rotational axis is pointed toward Polaris, a star we traditionally call the North Star, but this wasn't always so. 2000 years ago, the axis didn't point to any particular star and 2000 years from now it won't either. The precessional period for the Earth is about 26,000 years, all the while maintaining its 23.4° tilt.One precessional cycle takes 26,000 years.The Night Sky and Its MotionsThe objects in the sky appear to rotate from east to west each day but it is, in fact, the Earth that is rotating from west to east in front of the Sun, giving up both day and night. This is something you’ve known since grade school so nothing new here.

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