Download The Universe

The Universe
Chapter 1
Why was Astronomy important to the
ancients?
Natural Clocks
•Motion of the sun, moon, planets and stars
–plant crops, harvest crops
Location, Location, Location
•Sailors relied on the astronomy
–―Astronomy is the handmaiden to the sailor‖
________________
(2000 B.C.)
•
________ ___________
–Year
•12 months
–7 days a week
–
_______ _______ a year
–Day
•24 hours
•60 minutes / hour
•60 seconds / minute
•Stonehenge
_____________ Universe
(_________ ____________)
•The use of Stonehenge as an astronomical observatory
Apparent Path of the Sun
____________
•The ____________ ____________ __________ ___________
across the sky in the course of a year
–Plane of earth‘s orbit around the sun
________________
•____________ ___________ of ____________
•____________(―circle of animals‖)
–12 equal divisions
–________ _______ ________ one ―_______‖ each month
Sun‘s movement through Zodiac
Planets (―wanderers‖)
•______________ motion – the ___________ __________
__________ ___________ that a planet makes in its orbit about the
sun
Celestial Location
•__________ ___________
–A ____________ used by astronomers to __________ ____________ in
_______________
•Right ascension – analogous to longitude
•Declination – analogous to latitude
Finding the North Celestial Pole
___________ – the North Star
Celestial Distance
Circle
Circle
Circle
___________ ___________
•Angular size of an object determined by:
–_____________
–_______ ________
Parallax
•__________________ – the _________ __________ in
_____________
of an object ________________a ____________ of other objects
The Parallax Angle
Parsec
___________
The _____________ _____________ __________ of
astronomers
Two Beliefs on the Existence of Stars
Explanation for the Existence of Stars
What evolutionists believe
Sun
•Ordinary star
•Average brightness
•Massive, dense ball of gases
•Nuclear fusion reaction
Origin of Stars
•Starts as a ____________
–________________ _______________ of ______________ gas
•Gravity
–forms protostar
Large Magellanic Cloud
Protostar
•Begins as a cloud
–an accumulation of gases that will become a star
–Diameter
•Trillions of miles
–requires 1 x 1057 atoms
Protostar
•Gravitational attraction
–atoms accelerate toward center
–temperature increases
–Forms a dense sphere
•diameter
–1.5 million miles
Stable star
•Gravitational attraction
–nuclear fusion begins
–1.5 million miles
–begins stable life span
Star Interior
•___________
–_________ ___________
–15 million degrees °C
–Intense pressure
•300 billion atmospheres
–Density
•12x solid lead
–1/3 mass of star
Star Interior
•____________ _____
–Density of water
•____________ _____
–1/10 density of water
–surface emits visible light, UV radiation, and infrared
–5,500 °C
Life Span of Stars
•Sun
–Converts 1.4 x 1017 kg of matter to energy every year
•has enough hydrogen for 5 billion more years
Brightness of Stars
•_____________ ___________
–_____________ ____________ for different _________ of ____________ of
objects as __________ _______ ________
Brightness of Stars
•_____________ ___________
–A _____________ _____________ to _________________ for the
_______________ ___________ to the stars
–Standard distance
•10 parsecs = 32.6 light years
Brightness of Stars
•Absolute Magnitude
–Sun
•Apparent magnitude = – 26.7
•Absolute magnitude = + 4.8
Distribution of Radiant Energy from Sun
•Not all energy from a star goes into visible light (KNOW)
Star Temperature
•Star _________ _______________ _____ the ______________ of
the star
•Hot = ________
•Moderate = white/yellow
•Cool = ______
•Stellar Types and Temperatures
–O B A F G K M
Classification of Stars
Star Types
•Classification based on:
–_______________
–_______________
•Henry Russell (United States) 1910
•Ejnar Hertzsprung (Denmark) 1910
Hertzsprung-Russell Diagrams
Examples
Hertzsprung-Russell diagram
Hertzsprung-Russell diagram
H-R Diagram
Hertzsprung-Russell diagram
•__________ _________ __________
–average size, ______________ stars
–_________ __________ brightness, temperature, and ____________ ____ _________
Hertzsprung-Russell diagram
•______ ________
–___________
•Lots of surface area giving off light
–_____temperature
–Low density giants
•100x bigger than sun but with same mass
Hertzsprung-Russell diagram
•__________ ________ stars
–________
•small (2x earth size)
–________ _______
–Very dense
•mass
sun
Hertzsprung-Russell diagram
•Life Stages
–Evolutionary theory
•Sun
–Nebula
–main sequence
–red giant
–white dwarf
–Cold lump of carbon (black dwarf)
Hertzsprung-Russell diagram
•_________ __________
–stars that ________ _______ ___________ over a period of time
–magnitude
•.001X
•period
20x change
–seconds to years
–30,000 identified
Hertzsprung-Russell diagram
•Cepheid Variable Stars
–Bright variable stars used to calibrate brightness with distance
•Measure distances to other galaxies
Relative Sizes of Stars
The Life of a Star
Evolutionary Theory
Main Sequence Life Cycle
•Stable Star
–Nuclear Fusion
•_________ ___________ to ____________
Main Sequence Life Cycle
•Low on hydrogen fuel
•Star contracts
–expansion reduced
Main Sequence Life Cycle
•Collapse heats helium and remaining hydrogen
•Hydrogen fuses and layers expand
•Red Giant produced
Main Sequence Life Cycle
•Red Giant
–surface temperature
•4,000 °K
–1000x larger than main sequence
Main Sequence Life Cycle
•Red Giant
–After many years helium fusion begins in core
•100 million degrees required
–________ _________ into _________ in core
–red giant decreases in size (main sequence)
Main Sequence Life Cycle
•Helium core transformed into carbon core
–helium fusion begins in second shell
–expands to red giant again
Main Sequence Life Cycle
•Outer layers begin to pulsate from constant cycle of contraction and
expansion
•violent explosion blows off outer layers leaving hot core
Planetary Nebula
•Blown-off outer layers of star
•_________ ___________
•adds dust and gas between stars
•
Planetary Nebula
Main Sequence Life Cycle
•Carbon core and helium fusion shell gravitationally contract to form a
small dense white dwarf star
Main Sequence Life Cycle
•White dwarf star
–cools from white, to red, then to a black lump of carbon in space
Life Cycle of Star
High Mass Main Sequence
•After blowing off outer shells
–core contracts
–carbon fusion begins
•600 million degrees Kelvin
High Mass Main Sequence
•_________ ____________ continues (plus other fusion reactions)
until _________ is produced
•Iron fusion produces no energy
–star out of fuel
High Mass Main Sequence
•Star collapses and then violently explodes into a _____________
–produces brilliant light in sky lasting for months
•Elements from Iron to Uranium formed in explosion
1987A Supernova
(Before and After)
High Mass Main Sequence
•Remains of compressed core after supernova
–> 1.4 solar masses
•_________ ________ - small, very dense with center core of _______ __________
–> 3 solar masses
•black hole
Neutron Stars
•Gravitational force collapses nuclei forcing protons and electrons
together into neutrons
•super dense
–1011 kg/cm3
•super small
–10-20 km
•___________--___________ neutron star that emits _____
___________.
__________ _____________
•___________ _____________ _____________ the repulsive force
of all subatomic particles
•super super dense
–__________ ____________ _____________
•super super small
–0 radius
Explanation for the Existence of Stars
What creationists believe
Genesis 1:16
•And God made two great lights; the greater light to rule the
day, and the lesser light to rule the night: he made the stars
also.
Problems with Star Birth
•It is very difficult to get a gas cloud (nebula) to contract
because gases naturally expand
–The catch is that the conditions required to compress the gas to that
point seem to require the shock waves from the explosion of a
previously existing star
•Chicken/egg dilemma
Problems with Star Birth
•Almost every nebula is hundreds of times bigger than the critical size
needed to form a stable star
–―Precisely how a section of an interstellar cloud collapses gravitationally into a
star…is still a challenging theoretical problem…Astronomers have yet to find an
interstellar cloud in the actual process of collapse‖ Fred Whipple, The Mystery of
Comets, 1985
Problems with Star Birth
If a nebula were to begin contracting it would spin and that would
be a serious detriment to collapse because of the outward
centrifugal force
The spin would produce a powerful magnetic field that tend to
stop the collapse before a star could form
The birth of a star has never been observed
(KNOW)
―Despite numerous efforts we have yet to directly observe the process of stellar formation…The
origin of stars represents one of the fundamental unsolved problems of contemporary
astrophysics.‖ Charles Lada and Frank Shu, ― The Formation of Sunlike Stars‖, Science, 1990
•When dark nebula (mostly dust) collide with emission
nebula (fluorescent regions of gas) images like the Eagle
Nebula form. The result is whitish areas appearing at the
edges of the dark fingers of dust. Gases at such high
temperatures will quickly disperse.
Star death has been
observed (KNOW)
Supernovas
•A ______________, or ___________ ____________
____________, is one of the most brilliant and powerful
objects in the cosmos.
–Our galaxy, The Milky Way, should produce one supernova every
25 years.
–Supernovas cause a huge expanding cloud of debris
Supernova Remnants and the age of the
Universe
How Evolutionists Respond
•As the evolutionist astronomers Clark and Caswell say,
‗Why have the large number of expected remnants not been
detected?‘ and these authors refer to ‗The mystery of the
missing remnants‘. Clark and Caswell, 1976. Monthly
Notices of the Royal Astronomical Society, 174:267; cited in
Ref. 1.
How Creationists Respond
•There should be no mystery — Psalm 19:1 says: ‗The heavens
declare the glory of God; and the firmament shows his handiwork.‘
•Supernovas declare His mighty power, but are still only finite
expressions. The low number of their remnants is a pointer to God‘s
recent creation of the heavens and earth.
Star Degeneration
•Space _____________ _____________ universal trend of
________ ____________, not star formation
–Novas and supernovas
•Conclusion: the universe of created stars is slowly aging
–If black holes exist, they support this conclusion.
Facts about our Sun
•Ideal size to support life on earth
•The sun is in an ideal environment
–A single star
–Position in Milky Way Galaxy
–Fairly circular orbit
–Distance from Milky Way center
•Exceptionally stable
–Solar flares
Galaxies
_____________
•_________ of ____________ and billions of stars that _______ the _________ ____________
of the ____________
•________ __________ Galaxy
–200 billion stars
–________galaxy
•Billions of galaxies
–100 billion counted
Galaxy
•Clusters of galaxies
•Superclusters of galaxies
Cluster of Galaxies
(Virgo)
Milky Way Galaxy
•Galactic ___________
•Galactic ________
–Location of ______
•Galactic ________
Milky Way Galaxy
•How close is the sun to the center of the Milky Way?
Milky Way Galaxy
•The Sun is _________ _______ _______ from center of the galaxy
Milky Way Galaxy
•How big is the Milky Way?
Milky Way Galaxy
•____________ __________ ___________ in diameter
Milky Way Galaxy
•How long does it take the Sun to revolve around the nucleus?
Milky Way Galaxy
•Sun would complete one revolution every 200 million years
Milky Way Galaxy
•What is the Milky Way composed of?
Milky Way Galaxy
•__________ ____________ _________
•Thin concentration of gas, dust, and chemical compounds
–____________
–Iron
–Carbon compounds
–Silicon compounds
Milky Way Galaxy
•What is in the nucleus?
–red stars
•Little dust or gas
•5,000 light year radius
–_________ __________ __________
•1-2 light year radius
Milky Way Galaxy
•What is in the halo?
–Groups of massive red stars in clusters
Milky Way Galaxy
•What is in the disk?
–galactic clusters of stars
Other Galaxies
•Nearest neighbor
–dwarf spherical galaxy
•only 1,000 light years across
–80,000 light years away
–Milky Way has 11 satellite galaxies
Other Galaxies
•________________ Galaxy
–2 million light years away
–___________ in ________ and __________ to the Milky Way
–100 billion stars
Other Galaxies
•What is the farthest galaxy from Earth?
Other Galaxies
•Galaxy 4C41.17
•15 billion light years away
Other Galaxies
•What is the largest galaxy?
Other Galaxies
•Abell 2029
–60x size of the Milky Way
•100 trillion stars
•diameter of 6 million light years
Classification of Galaxies
•Edwin Hubble (1926)
–Elliptical galaxies (20%)
–___________ galaxies (50%)
–Barred galaxies (30%)
–Irregular galaxies
Bell Telephone Labs
•1920‘s
–Wanted to set up a radio-telephone communication system across
the Atlantic
–Sun‘s rays caused unwanted natural radio interference
–Set up research to study the problem
Radio Astronomy
•The first radio astronomy observations were made in 1932
by the Bell Labs physicist Karl Jansky who detected cosmic
radio noise from the center of the Milky Way Galaxy while
investigating radio disturbances interfering with transoceanic
telephone service.
Radio Astronomy Born
•1933
–__________ __________ also come from __________ ___________