National Science Olympiad

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National Science Olympiad Astronomy C Event
2010 Normal and Starburst Galaxies
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A. Normal Galaxies 1) The Milky Way Galaxy
(MWG) a) Globular Cluster M15
b) Galactic Black Hole Sag A
c) Eclipsing Binary Epsilon Aurigae 2) The
Andromeda Galaxy (M31) a) Globular
Cluster G1 3) The Triangulum Galaxy
(M33) a) Stellar Nursery NGC 604
b) X-Ray Binary M33 X-7 B. Starburst
Galaxies (Starburst/Normal) 1) M82 (The
Cigar Galaxy, in the M81 Group) 2) M101
(Pinwheel Galaxy, NGC 5457, in Ursa Major)
3) M84 (in the Virgo Cluster) 4) The
Cartwheel Galaxy (ESO 350-40, in Sculptor
Cluster) 5) C153 (in Abell 2125 Cluster)
C. Supernovas 1) Type Ia SN1994D (in NGC
4526) 2) Type II SN1993J (in M81)
NOTE There is not always a clear
distinction between normal and starburst
galaxies. Star formation takes place in both
usually a galaxy is classified as a starburst
galaxy if some sort of event has caused
intensified star formation, such as gravitational
disturbance from a nearby galaxy. The
classification of normal and starburst is
some- times arbitrary.
The Local Group
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• Normal Galaxies The Milky Way Galaxy (MWG)
• Multiwavelength Images

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• Normal Galaxies The Milky Way Galaxy (MWG)
• Structure and Location of Objects

Population I Population II Stars
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• Normal Galaxies The Milky Way Galaxy (MWG)
• Globular Cluster M15

Double Neutron Star Binary Systems (X-ray)
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• Normal Galaxies The Milky Way Galaxy (MWG)
• Sagittarius A (Sag A)

Chandra Images Animations Massive Star
Formation Black Hole Binary Swarm
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• Normal Galaxies The Milky Way Galaxy (MWG)
• Epsilon Aurigae Eclipsing Binary System
• http//www.citizensky.org/content/
  star-our-project

http//www.aavso.org/vstar/vsots/eps_aur.shtml
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• Normal Galaxies The Andromeda Galaxy (M31)
• Multiwavelength Images

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• Normal Galaxies The Andromeda Galaxy (M31)
• Globular Cluster G1

Mid-sized Black Hole 20,000 Solar Masses,
(Hubble)
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• Normal Galaxies The Triangulum Galaxy (M33)
• NOTE Sometimes M33 is still referred to
  as the Pinwheel Galaxy however M101 is commonly
  called the Pinwheel Galaxy
• and M33 is more commonly
  called the Triangulum Galaxy

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• Normal Galaxies The Triangulum Galaxy (M33)
• NGC 604 Stellar Nursery

Optical, Hubble
X-Ray, Chandra
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• Normal Galaxies The Triangulum Galaxy (M33)
• X-Ray Binary M33 X-7

Optical (Gemini)
Largest stellar mass black hole discovered. 16
solar mass black hole orbiting a 70 solar
mass star.
Eclipse of Black Hole by the Companion Star
(Chandra)
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B. Starburst Galaxies M82 (The Cigar Galaxy in
the M81 Group)
A one hundred million year gravitational dance
twelve million light years away results in
disruption and intensified star formation in
both galaxies, especially M82. In a few billion
years only one of these galaxies will remain.
M82
M81
SN1993J
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B. Starburst Galaxies M101 (Pinwheel Galaxy, NGC
5457)
M101 is 22 million light years away in the
direction of Ursa Major. M101 was selected by
NASAs Great Observatories (Chandra, Hubble,
Spitzer) to celebrate IYA the 400th anniversary
of Galileos telescope.
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B. Starburst Galaxies M84
M84 is 55 million light years away in the Virgo
cluster. M84 gives clues as to how galaxy sizes
are limited by the suppression of unlimited star
formation, similar to M33-x7 mechanism which
stops black holes from continuous mass accretion.
Hubble (optical)
M84
Chandra (X-ray) , VLA (radio)
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B. Starburst Galaxies The Cartwheel Galaxy (ESO
350-40)
The Cartwheel Galaxy is 400 million light years
away in the Sculptor cluster. The intense star
formation has been triggered by the passage of a
smaller galaxy through the middle of the
Cartwheel Galaxy. The trail of the intruder
galaxy is shown in the high resolution radio
image of the neutral hydrogen in the image on the
right. The bright areas in the Chandra image
are black holes which have resulted from the
formation of massive stars as a result of the
collision. The ring of star formation is 100,000
light years across
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B. Starburst Galaxies C153
C153 is 3 billion light years away in the Abell
2125 galaxy cluster. C153 is Moving at 4.5
million MPH through the cluster of galaxies. The
large scale Disturbance has resulted in star
formation being concentrated on one side Of the
galaxy, and the gas and dust from C153 is being
stripped away and trails the galaxy in 200,000
light year long streamers. 100 million years
ago The cluster containing C153 slammed into
another cluster of galaxies. C153 is losing the
gas and dust necessary for star formation, and
eventually will lose its spiral arm structure
entirely.
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C. Supernovas Type Ia SN1994D (in Galaxy NGC
4526)
NGC 4536 is 108 million light years away. SN1994D
is a Type Ia supernova event the thermonuclear
destruction of a white dwarf star in a binary
system, due to the accretion of enough mass to
exceed the Chandrashekhar Limit. Since all white
dwarfs have the same mass and therefore the
absolute magnitude of the event is known, Type Ia
supernova events are used to calculate distances
to galaxies.
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C. Supernovas Type II SN1993J (in M81 Galaxy)
SN1993J was a Type II supernova event the core
collapse of a massive star. The progenitor star
was a massive red supergiant and during the 250
years prior to its collapse its massive companion
star accreted 10 solar masses of
material, leaving the remnant deficient in
hydrogen and rich in helium. The companion star
survived the supernova event.
Light Echo
Companion Star
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Black Holes
Stellar Mass
Stellar mass sized black holes result from the
core collapse of massive stars in Type Ii
supernova events. M33 X-7 is a 16 solar mass
black hole the most massive stellar mass
black hole discovered to date. The smallest mass
black hole so far discovered is 3.8 solar masses.
Intermediate black holes are not the result of
the core collapse of a massive star, not are they
found in the centers of galaxies. They span the
range from The largest stellar mass black holes
to the smallest supermassive black holes. The
black hole found in M15 contains 20,000 solar
masses too large for a stellar mass black hole
and too small for a super- massive black hole.
There are many theories for their formation,
including coalescence.
Intermediate
Supermassive
Supermassive black holes are found at the centers
of galaxies. The black hole in the middle of the
Milky Way Galaxy is Sgr A and contains 3
million solar masses. The range for
supermassive black holes is from a million to
billions of times more massive than the sun.
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Cepheid and RR Lyrae Variable Stars
Period-Luminosity Relationship and The Distance
Modulus
M m -
5log10 (r)
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Mv 0.75
RR Lyrae Light curve Globular Clusters
Cepheid Light Curve - Galaxies
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Cepheid Instability Strip
RR Lyrae Strip

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Light Curves
Supernovas
RR Lyrae
Cepheids
Typical Eclipsing Binary
X-Ray Binaries M33 X-7

Epsilon Aurigae
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Cosmological Distances
Variables
Cepheids RR Lyrae
Spectroscopic Parallax
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Cosmological Distances
?Cepheids RR Lyrae
The Distance Modulus M m - 5log10 (r)

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?Type Ia Supernovae
Mv -19.5 
The Distance Modulus M m - 5log10 (r)

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Basic Equations and Relationships
The Distance Modulus M m - 5log10 (r)

10 Keplers 3rd Law (MA MB) a3

p2 Hubbles Law d
Vr H0 v d
a v 2p a vP Fc mac ac v2
r?2 t t
r 1 pc
206,265 au 3.26 ly 3.08 x 1016m 1
60 arcmin 60 1 60 arcsec 60? Inverse
Square Law L 1/r2 Circumference, Area, Surface
Area, and Volume of a Sphere
REARRANGE ALL EQUATIONS FOR EACH VARIABLE
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Resource Materials