Hint 1 how long does each day represent on the cosmic

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Hint 1.How long does each day represent on the cosmic calendar?Given that the cosmic calendar compresses the history of the universe into a single year, how much time does one day on the calendar represent?
10/28/2018CH 1 HW - (Practice)15/25ANSWER:Hint 2.Estimated age of the earliest human fossilsAccording to modern techniques for dating fossils, early humans arose within the past 3 to 5 million years.ANSWER:CorrectThe cosmic calendar compresses the 14-billion-year history of the universe into 1 year, which means that each day represents about 1/365 of 14billion years, or about 40 million years. Early humans arose just a few million years ago, which therefore means just a few hours before thepresent moment (the stroke of midnight on December 31) on the cosmic calendar.Key Concept: The Expanding UniverseLearning Goal:To understand what we mean by an expanding universe and how we know that the universe is expanding.The idea that we live in an expanding universe is fundamental to much of modern astronomy. But we can’t actually see the universe growing larger, so how dowe know that it really is expanding? This tutorial should help you understand the evidence. Now, click on the image below to launch the video:The ExpandingUniverse.Once you have watched the entire video, answer the follow-up questions on the right. You can watch the video again at any point.Part AWhich of the following statementsbestdescribes what astronomers mean when they say that the universe is expanding?Hint 1.How big is the observable universe?The size of theobservableuniverse depends on __________.ANSWER:about 1 million yearsabout 40 million yearsabout 1.2 billion yearsin Junein Septemberin mid-Decemberon December 30just a few hours before midnight on December 31
10/28/2018CH 1 HW - (Practice)Hint 2.What is a galaxy?A galaxy is best described as __________.ANSWER:
16/25CorrectKeep in mind that while the universe as a whole is expanding, individual galaxies (and gravitationally bound groups or clusters of galaxies) andtheir contents donotexpand. That is why the average distances between galaxies grow with time, but objects such as people, Earth, the solarsystem, and the Milky Way Galaxy remain stable in size.Edwin Hubble discovered two key observation facts: (1) Virtually every galaxy outside our Local Group is moving away from us. (2) The more distant the galaxy,the faster it is moving away. The raisin cake analogy shows how these two facts lead to the conclusion that the universe is expanding. Click “Play” to watch thevideo; observe the motions of the raisins and note how the values in the table change as the cake expands.

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Term
Summer
Professor
Angelichio

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