Bio 105 1st Edition Lecture 14Past Lecture (13)“I do not feel obligated to believe that the same God who has endowed us with sense, reason, and intellect has intended us to Fargo their use.” Galileo Galilei Origins of Diversity- We have been storytellers since the dawn of our evolution, and have narrative on how we got onEarth.- Science is relevantly new. - Cosmology-1. Nature and meaning of the universe generated from combining knowledge and wisdom. Dealing with the meaning of the universe. We gain this wisdom from education, experiences, etc. 2. Scientific cosmology is the study of the past, present, and future of our physical universe. Universe Today:Universe = largest unit on nature. All things, as a whole.H Hydrogen – 75%He Helium – 23%O Oxygen – 1%Other elements – remaining %- There are 92 naturally occurring elements on Earth (periodic table)- Structure of the universe – One millions earth’s can fit inside our single sun.- 1 light year is a distance (how far light travels.These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Galaxy – Massive collection of starts, gas, and dust kept together by gravity.- Earth to sun = 8 light minutes- Solar System = 5.5 light hours- “Stellar Region” - we have neighbor stars- The galaxy that our solar system is located in is the “Milky Way” on it Orion Arm.- From the within stars of the Milky Way appears a dim band.o 2/3of us public can’t see the Milky Way from their homes.Andromeda Galaxy – The closest neighbor galaxy, 2.5 m.l.y away.Telescopes are like time machines. “Look-back time” – we are looking at history, the past, when you look at the stars because of the distance light travels.o 8 minutes from earth to the sun.o the more distance an object is from us, the further back in time we are looking.o There are billions of galaxies with hundreds of billions of stars in each.History of Cosmology – There are hundreds to thousands of creation stories – fundamental to our well being. Traditional creation stories have similar:o Symbolic narratives of how the world began and how the first came to inhabit it.o Are sacred accountso Set in a dim and non-specific patho Speak to meaningful questions held by the societies that share themo They are means of transmitting valueWestern World (Judeo-Christian) universe was- Created by God thousand years old, perfect size of solar system, geocentric.Aristarchus (2300 BC) heliocentric views were rejected. Wandering stars= planetsRetrograde motion = pattern of starsPtolemy’s Scheme – (100 AD) used math and came up with Earth was the center of all. No one questioned this for hundreds of years.Copernicus – (Mid 1500’s) Through his finding he could make better predictions. He was afraid it would upset society. This findings explained retrograde motion better for the planets.Copernicus Revolution – turning point in world’s intellectual development, which laid the foundations of modern science and philosophy.Galileo became the target. He was questioned and criticized by the church/society and didn’t care. He changed the telescope and made it useful. He developed new technology, which drove discovery.Current Lecture (14)Galileo (early 1600s)- Developed Copernicus’s idea, “model”, and pushed it.- Telescopes showed the Universe was imperfect. For example, there were spots on the sun.- The Universe is much bigger than anyone thought it was.Universal Laws of Motion and gravityIsaac Newton (Late 17th – early 18th’)- First person to lay out laws of motion and gravity.- Actually spent more time studying and reading the bible.- Believed the universe was like a machine. “Clock-work universe”, the mechanical universe.- Thought everything was predictable.- Universe is deterministic.- Gravity as a force between two objects.Albert Einstein (early 20th)- Changed the understanding of Universe in ways that is still holding up.- Established our modern view of Universe.- General Relativity (1915) – replaced neutron’s theory of Gravity.- Einstein’s Universeo Described gravity in a new way.o Gravity not a force, nut a distortion of space and time.o Matter is a form of energyo Finding predicted on expanding or contracting and he didn’t accept that. He adjusted theequation to fit astatic ( non-changing, non-evolutionary) Universe.Edwin Hubble (early 20th)- Observed redshift* of galaxies- The indicated the expansion of space.- Dobbler Effect - The apparent change in wavelength of sound or light caused by the motion of the source, observer or both. Waves emitted by a moving object as received by an observer will be blue shifted (compressed) if approaching, red shifted (elongated) if receding. It occurs both in sound and light. How much the frequency changes depend on how fast the object is moving toward or away from the receiver. This explains redshift.- Hubble law – describes the movement of the galaxies away from each other as evidence by the red shift.- Space is increasing between galaxies created by redshift.- Discovery is the expansion of the Universe completely changed the discussion about its origin.There are two competing theories of the origin1. Steady State Theory – Universe has no beginning or end. Infinitely old, always the same (Fred Hoyles) But it doesn’t explain distribution of the elements.2. Big Bang – The Universe began as a super lot. Expansion of energetic radiation. Space and time comes into existence. - George Gamow and Georges Lemaîtice- Gamow predicted the radiation from initial events still in the Universe afterglow. Penzias and WilsonCosmic microwave background radiation (CMB). This was the most important discovery.- Steady state theory was no longer competition, the debate ends.- Falls in place about prediction made about Big Bang. - Serendipity – making fortunate discovery by accident.Science of Cosmology advances. Why? Because of evidence.Big Bang Theory explains- - Cosmological Redshift (dobbler)- Cosmic microwave background radiation.- Distribution of elements in Universe (abundance of Hydrogen)All findings have been consistent with predictions of the