Download memphis astronomical society short course in astronomy 2015

MEMPHIS ASTRONOMICAL SOCIETY
SHORT COURSE IN ASTRONOMY
2015-2016
STUDY GUIDE FOR CERTIFICATE EXAMINATION
If you would like to take the test, it is recommended that you prepare for it. It is not a
particularly difficult test, but you are expected to know most of the important concepts in
astronomy. You should not feel that the test is like a final exam in an astrophysics course, but
if you pass it, you can rightly be called a “Knowledgeable Amateur Astronomer”.
The various segments are listed below, with a brief synopsis of each. There is a link to each of
the lectures on our YouTube site. You should have a copy of the Short Course Manual.
If you can confidently answer the Questions posed in each section below, you will very likely
answer all the test questions correctly on that part of the exam.
If you are unsure about some of the concepts, by all means refer to the Short Course Manual
and watch the on-line lecture.
If you have any questions, please don’t hesitate to contact Bill Busler at [email protected].
Lecture #1 - Feb. 6, 2015:
Our Place in the Universe. By Bill Busler
An overview of the Universe providing a framework for the following lectures. Topics include
astronomical distance scales; the Milky Way and its contents, including stars, clusters, and nebulae;
the range of the human eye; the changing appearance of the Milky Way with the seasons; and other
galaxies and their enormous distances from us.
https://www.youtube.com/watch?v=wdgm204GYBQ
Questions: You should be able to describe the overall shape of the Milky Way Galaxy, indicate our
approximate location in it, and give its dimensions in light-years. You should know the definition of a
light-year and its equivalent in miles. You should be able to explain, perhaps using a sketch, why the
Milky Way looks different in the summer sky and the winter sky. You should be aware of the typical
(approximate) distances to bright constellation stars, compared to the dimensions of the Milky Way.
Lecture #2 (Parts 1 & 2) - Apr. 10, 2015
The Sky and the Earth. By Bill Busler.
Star maps, constellations; effects of the Earth’s rotation and revolution and the observer’s latitude;
circumpolarity; the celestial coordinate system; sidereal and solar time; the seasons; and precession.
Part 1: https://www.youtube.com/watch?v=-8E1RkGMai4
Part 2: https://www.youtube.com/watch?v=OLtiW-91xok
Questions: You should be able to define and explain the celestial equator, the ecliptic, solstices, and
equinoxes. You should understand why some constellations are circumpolar, and be able to name
some of them at our latitude. You should understand the difference between a solar and a sidereal
day, explaining the concept with a sketch. Be able to define declination and right ascension. Know
what precession is, and its two principal results as seen in the sky.
Lecture #3 - May 1, 2015
Sun-Earth-Moon Relationships. By Bill Wilson
Phases of the Moon, including the Moon’s shape, the names of the phases, their times of rise, transit,
and set; Earthshine; rotation and libration; solar eclipses (total, partial, and annular); lunar eclipses;
tides.
https://www.youtube.com/watch?v=L4TbEoiGe_o
Questions: You should understand the cause of the lunar phases, the shape and name of each phase
and how long it lasts, and approximately when the Moon rises, transits, and sets when in each phase.
Know the geometry of solar and lunar eclipses, and when each can occur. Understand what causes
the tides, and the difference between spring and neap tides.
Lecture #4 - Jul. 10, 2015
The Solar System and Its Origin. By Bill Busler
Review of basic facts about our Solar System, especially its overall shape and the orbital motions of
the planets, their satellites, and comets; old and new theories of the origin of the Solar System.
https://www.youtube.com/watch?v=YNvj4W9QXG0
Questions: Know the overall basic shape of the Solar System and the reason for it, according to
modern theories of its formation. Know where the main asteroid belt is. Explain how if the Sun and
planets had a common origin they are so different from each other today. Know where comets come
from, according to modern theories.
Lecture #5 - Jul. 10, 2015
Optics and Telescopes. By Tom Richardson
Principles of operation of the basic types of telescopes (refractors, reflectors, and catadioptrics), and
the relative merits of each; suitable eyepieces and magnifications for observing different types of
objects; how to select a telescope.
https://www.youtube.com/watch?v=qQsbxX7OZEo
Questions: You should be able to state the differences between the basic types of telescopes.
Understand the terms focal length, f/ ratio, magnification or power, and be able to calculate the
magnification of a telescope from given information. Explain which type of telescope is most suited
to observing different kinds of celestial objects. Know how to calculate the maximum useful power of
a given telescope.
Lecture #6 - Aug. 7, 2015
Early History of Astronomy. By Bill Busler
A brief review of the early astronomers, from the Babylonians, Egyptians, and Greeks to the great
discoveries and insights of Copernicus, Tycho, Kepler, Galileo, and Newton.
https://www.youtube.com/watch?v=QqhU-xlxdYU
Questions: Be able to describe the two basic world views about the layout of the Solar System, which
early astronomers held each, and why they did so. Be able to state and explain Kepler’s three Laws of
Planetary Motion. State an important astronomical contribution of each of the great astronomers
listed above. Be able to explain how modern techniques (such as telescopes and photography)
played an important role in the acceptance of the more modern world view of the Solar System.
Lecture #7 - Aug. 7, 2015
Techniques for Locating Celestial Objects. By Bill Busler
Tried-and-true methods for locating and observing every type of celestial object with your telescope,
from the obvious to the challenging.
https://www.youtube.com/watch?v=lQSPReBwjQ0
Questions: None. However, you should review this material in preparation for earning the various
M.A.S. Observing Awards, which can be thought of as the laboratory component of the Short Course.
Lecture #8 - Sept. 11, 2015
Measuring Distances in the Milky Way. By Bill Busler
Some early attempts to determine the diameter of the Earth, the distance to the Moon, and the scale
of the Solar System; measuring distances to the planets; using parallax to obtain the distances to the
nearest stars.
https://www.youtube.com/watch?v=J7VBPpzqNc4
Questions: No specific questions. The material in this Chapter (and lecture) can be used as helpful
background for understand the work of early astronomers (Lecture #6), as well as a preparation for
Lectures #9 through #12.
Lecture #9 (Parts 1 & 2) - Oct. 2, 2015
Classification and Measurement of Stars. By Bill Wilson
The magnitude scale of Hipparchus; nomenclature of stars; spectral classification; distance
determination; absolute magnitude and luminosity; size and density of stars; and the HertzsprungRussell diagram.
Part 1: https://www.youtube.com/watch?v=2htxDPdF53A
Part 2: https://www.youtube.com/watch?v=2Q8QPfJtmUU
Questions: You should be able to draw a Hertzsprung-Russell diagram, label the coordinate axes,
sketch the so-called “Main Sequence”, including blue giants and red dwarfs. Indicate the Sun’s
position. Indicate the position of red giants, red supergiants, and white dwarfs. Know what
determines the color (spectral classification) of a star. Be aware of the magnitude scale and the
difference in brightness between magnitudes. Be able to calculate the apparent brightness of one
star relative to another, given their visual magnitudes (as integers).
Lecture #10 (Parts 1 & 2) - Nov. 6, 2015
Stellar Evolution. By Bill Busler
One of the cornerstones of modern astronomy: the formation of stars from nebulae and their life on
the main sequence; supergiants, variables, planetary nebulae, supernovae, dwarfs, pulsars, neutron
stars, and black holes.
Part 1: https://www.youtube.com/watch?v=FzSW4_w6Cfc
Part 2. https://www.youtube.com/watch?v=e_epJ_LwJik
Questions: Be able to distinguish between the various types of nebulae – dark, emission, reflection,
planetary – and their roles in the modern theory of stellar evolution; give examples of each. Using an
H-R diagram, describe the evolutionary track of a solar-type star and a blue giant star, including the
end stages of each. Define white dwarf stars, red giants, supergiants, neutron stars, pulsars, and
black holes, including their place in stellar evolution.
Lecture #11 - Dec. 4, 2015
Galaxies. By Bill Busler
The origin of the Universe; types of galaxies and their evolution; stellar populations within galaxies;
Seyfert galaxies and quasars.
https://www.youtube.com/watch?v=eGQza3ZLUkU
Questions: Combined on the test with #12 (below).
Lecture #12 – Feb. 5, 2016:
Cosmology. By Bill Busler
The use of Cepheid variables as “yardsticks” to nearby galaxies; distance determinations to more
remote galaxies; the red shift and Hubble’s constant; the “Big Bang” and the expanding Universe; the
age of the Universe.
https://www.youtube.com/watch?v=q-iqyO-YmZs
Questions: Define and explain “red shift” and “blue shift” and show how those phenomena can be
used to measure the radial velocities of stars and galaxies. Explain how Cepheid variable stars can be
used to measure the distances to other galaxies. Be able to sketch a Hubble diagram, label its axes,
and show what it indicates about the Universe. Explain how this diagram led most astronomers to
accept the “Big Bang” theory of Lemaître and Hubble.