Earth, Life and TimeDr. RampinoSpring 2022Science Core-Life ScienceStudy Guide for EXAM 1I.DEEP TIMEWhat is Science?-Science is testable and open to rejection or acceptance. It is the bestway we understand the planet.Bishop Ussher’s age of the Universe/Earth = 6,000 years origin in 4004 BC-Based on biblical events, bishop usher calculated that the earth was formedOctober 23, 4004. Meaning the universe/earth was about 6,000 years old. Thisview was adopted by the church.Nicholaus Steno—in mid-1600s-He was the one who figured out that tongue stones were shark teeth. And foundout the rocks were made of ocean sedimentsFossils occur within rocksSteno’s Laws-Steno had three laws of sedimentary rocks.-the oldest layers are deposited at the bottom and youngest layers on the top-the rocks are thick, with thickness about 100 and 100 feet- the rocks were originally deposited in horizontal layers- he also figured it took more than 6,000 years for the rocks to form.Original Horizontality of Sedimentary RocksJames Hutton and the discovery of Deep Time in late 1700s-Based on this, Hutton was able to discover deep time. He studied deposition ofsediments and found a geological concept of angular uncorfmity. This is whenlayers A-d are deposited. Then they become folded into a mountain. The mountainbecomes washed away and a new layer E is deposited on it.The rate of this wascm/per 1,000 of years.-Proving that human history on earth is non significantII.DEEP SPACEThe Geocentric Universe of Aristotle-Aristotle thought that the earth was the center of the universe, and that heavyobjects fell because they were trying to get to the center of the earth. He alsoproposed that the ‘fixed stars’ were the end of the universe and anything beyondthat was the realm of God. His view was also backed by the church.Ptolemy and EpicycLes to explain planet positions-Ptolemy thought you could use epicycles, wheels in wheels to tell the position ofthe planets, and this could explain mercury retrograde.-He found that the ‘fixed stars’ maintain their relative positions as they move1
-His concept was very complicated using a geocentric view of the universeHeliocentric Universe—Nicholas Copernicus in 1543-Proposed that the earth revolved around the sunEarth and other planets orbit the Sun—much simplerGalileo Galilei (1609)—Evidence for Heliocentrism—Telescopic observationsMoons of JupiterPhases of VenusMilky Way composed of individual stars not visibleto the naked eyeConstellations—Not real groupings of stars—Astrology has no basisGalaxies and Clusters of GalaxiesIII.THE UNIVERSELight year (unit of distance)= 6 trillion miles= 6 x 1012milesDistance to the nearest stars in light years? 4 Lt yrsThe Milky Way Galaxy– size and shape—disk shaped spiral galaxyMilky Way Galaxy contains about 400 billion starsUniverse composed of many galaxies; maybe more than 100 billion galaxies!