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Astronomy 1 — Elementary Astronomy LA Mission College Spring F2015 Quotes & Cartoon of the

“One may wonder, What came before? If space-time did not exist then, how could everything appear from nothing? . . . Explaining this initial singularity—where and when it all began—still remains the most intractable problem of modern cosmology. — Andrei Linde “But who shall dwell in these worlds if they be inhabited? ... Are we or they Lords of the World? ... And how are all things made for man?” — Johannes Kepler “Our is one of 100 billion in our galaxy. Our galaxy is one of billions of galaxies populating the universe. It would be the height of presumption to think that we are the only living things in that enormous immensity.” — Wernher von Braun Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Announcements

• Observing Project & Extra Credit Due • Midterm graded & gradebook updated to drop lowest • remainder of grading (hopefully) updated this weekend • Final 12/15 at 10-12 AM!

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Last Class

• Debrief Midterm • Debrief LT • Cosmology & Fate of the Universe • (time permitting)

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 This Class

• Review/Debrief Midterm • Exoplanets (time permitting)

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 About the Final

Astronomy 1 — Elementary Astronomy LA Mission College Spring F2015 About the Final

• Similar format to Midterms • Similar length • a little longer, some choice of questions • Little new material, mostly cumulative • Study the stuff on the midterms! • But don’t memorize the questions themselves, you probably won’t see many that are identical • You may bring a full sheet of notes • both sides • handwritten

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 About the Final

• Don’t leave stuff blank! • Can you remember ANYTHING about the topic? • Apply logic! • Comprehension before Computation -- Big Picture before Details • State units with numbers (except magnitude)

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Topics

Astronomy 1 — Elementary Astronomy LA Mission College Spring F2015 TOUR OF UNIVERSE Our “Cosmic Address” • LAMC • Sylmar • Los Angeles County • CA • US • • • Milky Way Galaxy • Local Group • Virgo Supercluster • The Universe Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 SCIENCE Science

• Definition • Method • KEY: Hypothesis, Test, Revision • Nomenclature -- Hypothesis, Theory • Characteristics of Science & Belief System • Be able to recognize science and not-science • Be able to recognize a scientific hypothesis • Be able to describe the scientific method

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 THE NIGHT SKY Diurnal Motion

• Daily • Everything Rises in East, sets in West • Moves in circles around the NCP (and SCP) • Earth is rotating • Be able to answer questions using diagrams from the Position LT

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Lunar Phases

• Cause of phases • ID of phases • Timing of rise/set/

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Eclipses

• Solar and Lunar • Cause • Geometry • Timing • Why not every full/new moon

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Zodiac & Apparent Solar Motion

Name:______!! Date:______ICE 2! ASTRO 110/120! Levine Spring 2013

• Ecliptic • Zodiac • Meaning of “The Sun is in Taurus etc.” • Takes a to cycle through

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Seasons

• It’s the axial tilt • It’s about energy transfer • Be able to discuss observable consequences • when is the Sun high in the sky, day length etc.

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 OLD DEAD GUYS Greeks to Kepler

• Greek ideas • Copernican Revolution • Tycho Brahe • Kepler the dude

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Kepler’s 3 laws of Planetary Motion

1. The orbits of the are ellipses, with the Sun at one focus. 2. A line from a to the Sun sweeps out equal areas in equal periods of time • Planets move fastest when physically closest to the Sun, and slowest when farthest. 3. A planet’s squared, is proportional to it’s farthest distance from the Sun cubed: • P2 = a3 • Be able to recognize these • Work with ellipses and eccentricity • Recognize examples of 2nd and 3rd law (faster/slower longer period/ shorter period) • Possible calculation with 3rd law Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Kepler to Sir Issac

• Galileo • Sir Issac • Contributions and fields of study • Law of Universal Gravity

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Law of Universal Gravity

• Be able to explain how the force varies (larger or smaller) with of either object, both objects and distance • Be able to work the inverse square relationship -- how does force change if distance doubles....

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 LIGHT, OPTICS, TELESCOPES Nature of Light

• Why this is important for Astronomy • electromagnetic radiation • waves, particles, duality • all light, from radio to gamma ray is same thing • all light travels at the same speed in vacuum • c=3x108 m/s

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Properties of Light • Waves • Relationship of wavelength and • λ = c/f • Interference • Particles • Photoelectric effect • E = h f = hc/λ • h = 6.6 x 10-34 Js = 6.6 x 10-34 J/Hz • Know what these relationships mean • Know how the ranking task worked • Possibility of seeing a a simple calculation Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Electromagnetic Spectrum

• difference between red and blue light • Basic bands of EMR (e.g. radio, visible, IR etc.) • Relationship between band, wavelength & Energy

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Telescopes and Observatories

• Refractors and Reflectors • Size (of primary) matters • Atmospheric Transmission & Seeing • Multiwavelength Astronomy • What are IR and Radio good for? • Cameras & Spectroscopes

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 SOLAR SYSTEM Solar System Properties

• Overall “bulk” properties • Disk shape • two types of planets • Space “debris” • common age

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Solar System Properties

• “Anatomy” What and Where • Sun • Inner SS & terrestrial planets • • Outer SS & Jovian planets • Kuiper Belt • Heliopause • • Size/Distance Scales

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Solar System Formation

• Raw materials -- big bang, role of supernovae • Theories of Formation • Solar Nebula Theory • Differentiation • Frost line • Planet formation -- both types • Disk clearing • Cratering & Craters

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Solar System Bodies

• Terrestrial Planets • common properties • dynamo effect • What went wrong for Venus and Mars • Greenhouse effect • Jovian Planets • common properties • Why are Titan and Enceladus interesting • Why isn’t Pluto a “planet” and what it is

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 STARS & GALAXIES Stellar Properties

• • Magnitude system • Apparent vs. • review the ranking tasks • Distance ladder & difficulty of distances • Stellar • know how angle & distance relate • Standard Candle • how does a standard candle work

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Color and & Size

• stars are (mostly) like blackbodies • temperature and peak wavelength • temperature and size & luminosity

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Spectral Type

• Color ~ temperature ~ spectral class • be able to answer questions based on the blackbody LT • Harvard computers & Harvard classification scheme • OBAFGKM • Brightness and temperature and size (Giants)

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 HR Diagram

• What is it? • What can be plotted on it? • • Red giants • Supergiants • White Dwarfs • Evolution

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Stellar Lifecycles

© NASA • formation • Main Sequence lifetime • End states and what determines them • Mass is everything!!!!! • More mass means shorter life Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Main Sequence & phase

• Main Sequence • Hydrostatic Equilibrium • H to He nuclear fusion • Most of a star’s life • Sun is on MS • Red Giant • New hydrostatic equilibrium • H to He fusion in shell • He fusion in core • 1/10th the duration of MS lifetime

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Endgame Scenarios

• Giant stars • Planetary nebulae • White dwarfs • Type II supernovae • neutron stars & pulsars • black holes • type Ia supernovae

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 The Milky Way

• Barred Spiral • General structure • disk, bulge, halo • General Content • Where are we?

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Galaxy Classification

NASA/ESA

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Characteristics of types

• Describe spirals, barred spirals, ellipticals, irregulars • Which are most common? • What are their overall properties? • Which tend to have older or younger stars • Which tend to have black holes (all)

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 COSMOLOGY Telescopes are Time machines

• Lookback time • Concept of the Observable Universe

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Expanding Universe

• Space is expanding, not stuff • Raisin bread & balloons • Role of gravity in holding structures together • Cosmological principle

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Big Bang

• NOT an explosion • Universe was infinite immediately • How long ago was it? • The whole universe was in a hot, dense state • energy became matter became stars and galaxies • Evidence for Big Bang • Expansion • H,He,Li abundance in early universe • Cosmic Microwave Background

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Cosmic Microwave Background

• Penzias & Wilson • 2.7 K • Very smooth but somewhat bumpy • Not the very beginning, 380,000 after BB

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Fate of Universe

• 3 fates: Open, Closed, Critical or Big Crunch, Big Chill/ Big Rip • Dark Matter & Dark Energy • Most of universe is dark • Dark Matter • Dark energy dominates universe • Dark energy is unknown cause of local expansion

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 EXOPLANETS Exoplanets

• If we get to them today…

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 IN SUMMARY… The Galaxy Song

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 So Long and Thanks for All the Fish!

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Other Worlds

Extrasolar planets and systems

Astronomy 1 — Elementary Astronomy LA Mission College Spring F2015 There are a lot of planets out there!

• 1879-1935 extrasolar planets around 1225 stars • 471-484 multiple planet systems • http://exoplanet.eu/ catalog/ • Simple flat-table list • 4696 Kepler candidates!

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 There are a lot of planets out there!

• 298 are very large • Radius larger than 6x Earth • 150 are small • Radius less than 1.25 x Earth

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 DETECTION METHODS How do we find them?

• Direct imaging • Rare • (RV) • Planet induces doppler shift in parent star • Transit • Planet blocks light from parent star • Gravitational microlensing • Planet causes background object to brighten • • Planet causes parent star to shift position periodically Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Image

Beta Pictoris b (bright spot) orbiting its star (center) Credit: Bruce Macintosh et al. • about 63.5 light years from Earth • Beta Pic b (planet) • dist from Beta Pic about 9x dist Earth from Sun • VERY large, ~ 1.6x radius of

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 RV Animation

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Transit Method Animation

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 KEPLER Kepler

• Capable of finding earth-sized planets in the habitable zone of nearby stars • Transit method • 962 confirmed planets to date • Now in modified extended mission K2 (has lost 2 reaction wheels)

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Kepler Overview

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 MOST EARTHLIKE PLANET “EARTH 2.0” KEPLER 452B Transit Graph

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Artist’s Concept

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Kepler 452b

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Kepler 186-f came first

• Kepler 186f discovered April 2014 was first Earth-size planet in Habitable zone. • Composition not as clearly confirmed as rocky • Orbits very close to a dim M-type Star • about 500 ly distant

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015 “Earth 2.0” Kepler 452b

• Discovered July 2015 (press con 7/23) • Orbits G-type Star • about 1400 ly distant

Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015