Supernovae
by Josh Klimek
Image of SN1994D from http://www.321space.com/gallery_page.html?gallery=stars&image=opo9919i
Historical Observation of Supernovae
Most Recent Supernovae
•1054 the Crab Nebula
•1572 observed by Tycho Brahe
•1604 observed by Kepler
•1987
Image from http://members.aol.com/Artstellar/nova.JPG
What is a Supernova?
Star life cycle image from - http://www.star.ucl.ac.uk/groups/hotstar/images/life_cycle.jpg
Why do supernovae occur?
Two Types of Supernovae
Type Ia
Type II
Evolution of a 25 M☼ Star
Stage
Duration
Hydrogen Fusion
7*10^6 yrs
Helium Fusion
7*10^5 yrs
Carbon Fusion
600 yrs
Neon Fusion
1 year
Oxygen Fusion
6 months
Silicon Fusion
1 day
Table values from Universe 7e pg498
Chandrasekhar limit http://www.physast.uga.edu
Further Differences Between the Two Types
•Absorption spectrums
•Luminosity
Image from http://rst.gsfc.nasa.gov/Sect20/3_32.gif
How Powerful is a Supernova?
"The energy produced by a supernova is mind-boggling: 1044 joules. Is it the
same as if each and every gram of the earth's mass was converted to a nuclear
bomb 200 times more powerful than the one dropped on Hiroshima." http://www.religioustolerance.org/ev_young3.htm
•Earth’s mass = 6x1024 kg
•6x1024 kg = 6x1027 g
•200 x 6x1027 = 1.2x1030 Hiroshima bombs
“The power produced by a supernova is “100 times more energy than our sun
has emitted in its 4.56 billion year history.” (Freedman pg 499)
“The rate at which it emitted energy in the form of neutrinos—was 10 times
greater than the total luminosity in electromagnetic radiation in all of the star in
the observable universe! (Freedman pg 503)
SN2005A Data
•Type Ia – Supernova in a Binary System
•Amberstar A – M1 Ia, Red Supergiant 8.6 light years away from earth
• Apparent magnitude m= -8.6
•Amberstar B – Hot White Dwarf known as a supersoft x-ray source (+500,000K)
• White dwarf is not visible to the naked eye.
• SN2005A occurred at 10:00 PM on 1.1.2005
•apparent magnitude m= -22
•Apparent Magnitude of the sun
•m= -27.7
•Apparent magnitude of the Moon
•m=-12.7
Image from http://archive.ncsa.uiuc.edu/Cyberia/NumRel/Images/massxfer.gif
Observational Data on Sirius (Amberstar)
Location: Olympia Wa
Day
Date
Rise Conditions
10:00 PM Conditions
Set Conditions
Sun Rise
Sun Set
1
1.1.05
8:45 PM ESE NIGHT
13° SE HORIZON NIGHT
5:50 AM WSW NIGHT
8:59 AM
5:31 PM
15
1.15.05
7:45 PM ESE NIGHT
19° SE HORIZON NIGHT
4:50 AM WSW NIGHT
8:54 AM
5:48 PM
30
1.30.05
6:45 PM ESE TWL
24° SSE HORIZON NIGHT
3:50 AM WSW NIGHT
8:40 AM
6:10 PM
40
2.9.05
6:00 PM ESE SUN 3° WSW HORIZON
26° SSE HORIZON NIGHT
3:15 AM WSW NIGHT
8:26 AM
6:26 PM
50
2.20.05
5:30 PM ESE SUN 11° WSW HORIZON
26° S HORIZON NIGHT
2:30 AM WSW NIGHT
8:08 AM
6:42 PM
59
3.1.05
4:45 PM ESE SUN 20° SW HORIZON
25° S HORIZON NIGHT
1:55 AM WSW NIGHT
7:52 AM
6:55 PM
74
3.15.05
3:45 PM ESE SUN 32° SW HORIZON
22° SSW HORIZON TWL
12:55 AM WSW NIGHT
7:25 AM
6:55 PM
How Bright Did it Get?
Abs Magnitude
Apparent Magnitude
1
-5.6
-8.5
1.04
-16.4
-19.3
15
-19.6
-22.5
30
-17.9
-20.8
40
-16.8
-19.7
50
-16.4
-19.3
59
-15.8
-18.7
74
-15.5
-18.4
100
-14.9
-17.8
150
-14
-16.9
250
-12.1
-15
Magnitude Trends vs Time, as Observed from Earth
-25
Apparent Magnitude
Day
-20
-15
-10
-5
0
50
100
150
Days
Apparent Magnitudes
•Sun = -27.72
•Moon = -12.7
•Venus = -4.4
•Sirius = -1.5
200
250
300
What would be the biological implication of a near earth supernova event?
Is it possible to predict the occurrence of a supernova?
What is Left Behind?
Further Questions?
Image from http://www.dcs.gla.ac.uk/~mc/images/Digital/Supernova.jpg