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Astronomy
Astronomy
 The
study of the planets, stars,
and other objects in space.
History

Nicolaus
Copernicus
Polish Astronomer
 1st suggested the
sun was the center
of the solar system
 Put six known
planets in proper
order.

History

Galileo Galilei
Italian Scientist
 Greatest contributions were his descriptions
of moving objects.
 Laid groundwork for the study of gravity by
demonstrating the weight of an object does
not affect its rate of fall.
 Discovered four moons of Jupiter
 Observed and recorded the phases of Venus

History
 Galileo
Galilei
 Studied
the moon’s surface
 Tracked sunspots
 Tried by Inquisition in the 1600’s for
teaching against current belief of the
Catholic Church.
 Declared
innocent by John Paul II in 1980
History

Albert Einstein
German born
American physicist
 Developed the
Theory of Relativity
(E=MC^2)

 Explained
the
motion of particles
traveling at the
speed of light.
History
 Edwin
Hubble
 American
Astronomer
 First discovered
light beyond our
galaxy.
Instruments
 Refracting
Telescope
 Uses
an
objective lens to
collect light
coming from an
object in Space
 Galileo
Instruments

Reflecting
Telescope

Uses mirrors to
reflect and form a
magnified image of
an object which is
seen through a
lens.
 Issac
Newton
Instruments

Radio Telescope


Consists of a reflector,
a receiver, and an
antenna and focused
on a receiver.
Radio waves are
collected by the
antenna and focused
on the receiver

Grote Reber
Instruments

Spectroscopes


Separates light into
wavelengths by means
of a glass prism or
ruled gratings.
Used to determine
elements in a star
Instruments

RADAR

System that
detects an object
beyond the range
of visible light.
 Used
to determine
an object’s distance
or range.
Origins
 Universe
Big
Bang Theory
A cosmic
explosion occurred 15
to 20 billion years ago.
Sent
matter and energy in all
directions
From this matter all objects in the
universe developed.
Origins
 Solar
System
 Nebular
Hypothesis
A nebula
(gas and dust pulled
together by gravity) collapsed due to
gravitational forces.
 Flattened
by gravity, rotation, and
pressure
 Regions of condensation eventually
became the sun and planets, moon
and other space objects.
The Sun
The Sun
 A medium
sized yellow star
composed mostly of hydrogen
and helium.
 Exerts gravity on the planets
keeping them in orbit.
The Sun
 Structure
 Core
Up
to 15,000,000 degrees Celsius
Hydrogen and Helium are in constant
motion
 Hydrogen
is fused into Helium
 This releases the sun’s energy
The Sun

Photosphere


Chromosphere


Innermost layer of the sun’s atmosphere
Middle layer of the sun’s atmosphere
Corona

Outermost layer of the sun’s atmosphere
 Although
its average temperature is over
1,000,000 degrees it produces little heat.
The Sun
 Activity
Sunspots
Dark,
cooler areas on the
photosphere
Caused
by disturbances in the
sun’s magnetic field
The Sun
 Activity
Solar
Flares
Intense
magnetic storms on the
sun’s surface.
The Sun
Activity
Prominences
Arcs
of gas that erupt from the
surface of the sun.
Comet
A small
mass of ice, rock
and dust
Comet

Orbit the sun in an elliptical orbit

Have varying periods of revolution (Comet to
Comet)
 Hailey’s
Comet appears every 76 years. (2061)
Originate in an area outside our solar
system
 Tail – particles of the comet that have
been vaporized and forced away from the
sun.

Asteroids
 Small
rocky bodies orbiting the
sun in the same direction as the
planets.
Asteroids

Most are found in a region between Mars
and Jupiter


Believed to be fragments of pre-planet
material.


Known as?
What does this mean?
Some cross earth’s orbit

Meaning?
Meteoroids
 Similar
to asteroids but
smaller.
Meteoroid

Meteor

A meteoroid that enters Earth’s atmosphere
 Burn
up as a result of friction with gas particles
 “Falling Star”

Meteorite


A meteor that doesn’t completely burn up and
reaches Earth’s Surface.
Meteor Shower

Occur when Earth passes through debris left
in a comet’s orbit.
Stars
 Bright
Spheres of gas
 Energy
fusion.
is produced by nuclear
Stars
 Properties
 Magnitude
Brightness
based on its composition
and distance from the earth.
– Actual brightness
 Apparent – Brightness as in appears
from Earth
 Absolute
Stars
 Properties
 Color
Related
to temperature
– Blue
 Cooler – Red
 Medium - Yellow
 Hot
Stars
 Properties
 Hertzberg-Russell
Graphs
diagram
absolute magnitude vs.
temperature
Used to predict the how long stars will
live
Life Cycle
 Nebula
 Cluster
of gas and dust pulled
together by gravity.
Star
Forming Regions
 Why
would they get this name?
Stars
 Life
Cycle
 Protostar
Beginning
 Nuclear
stage in star formation.
formation begins
Stars
 Life
Cycle
 Main
Sequence
Hydrogen
changes to helium
May last billions of years
 Dependant
on mass
Stars

Life Cycle

Red Giant
 Outer
surface cools, expands, and becomes red.
Stars
 Death
 Final
stage depends on mass
 Low
Mass
 Red
Giant collapses and becomes a white
dwarf
 Medium
Mass
 Forms
planetary nebula (Shed their outer layer)
then a white dwarf
 Massive
 Form
supernovas then may become a very
dense neutron star or an extremely dense black
hole.
Other Stellar Objects
 Pulsars
 Spinning
neutron stars that send out
beams of radiation.
 Quasars
 Very
bright centers of some distant
galaxies.
Constellations

A group of stars that form a pattern.
88 accepted worldwide
 Used for navigation
 Circumpolar – 5 constellations seen
throughout the year that revolve around the
North Star

Major – Great Bear (includes part of Big
Dipper)
 Ursa

Points to the North Star
 Ursa

Minor – Little Bear or Little Dipper
North Star (Polaris) is at the end of its handle.
Constellations
 Zodiacal
 Band
Constellations
of 12 constellations moving across
the sky throughout the year
Galaxies
 Huge
system of billions of stars
held together by gravity.
Galaxies
 Spiral
 Disk
shaped with a bulge in the
center and spiral arms
Examples
 Milky
Way
 Andromeda
Galaxies
 Elliptical
 Slightly
flattened spheres with bright
centers.
 Very
little gas and dust.
Galaxies
 Irregular
 No
regular shape.
Many
stars
Great clouds of gas and dust.
 Examples
Large
and Small Magellanic Cloud