Everything up until the final Flashcards
What is the air made up of?
80% Nitrogen, 20% Oxygen
What is the freezing point of water in Fahrenheit?
32 Degrees F
What is the boiling point of water in Fahrenheit?
212 degrees F
What is the lowest temperature in celcius?
-273 degrees C. OR 0 Kelvin
How do you find Kelvin if you’re given the temperature in Celsius?
K = C + 273
What are the “4 forces” ?
1) Gravity/ levity
2) EM force (electromagnetic)
3) Strong
4) Weak
What does Strong force do?
Hold the nucleus together. With the protons having the same charge they naturally want to repel one another but strong force holds them together.
What is Weak force?
Something to do with radioactivity??? idk half life or some shit.
What is the surface(photosphere) temperature of the Sun?
6000 Kelvin
What colour do “cool stars” appear?
RED
What colour do “hot stars” appear?
BLUE
What are the wavelengths from shortest to longest?
Shorter waves have higher energy
Gamma ray
X-ray
Ultra violet
Visible light
Infrared
Microwave
Radio wave
Longer waves have less energy
What is an Alpha particle?
Helium nucleus consisting of 2 protons and 2 neutrons.
What is a Beta particle?
Electron
What are 7 different types of stars?
1) Red/Blue Giants
2) Red/Blue Dwarfs
3) Neutrons
4) Quorks
5) Black hole
6) Variable
7) Binary stars
How far away is the Sun?
93 million miles, 150 million km, 8 light minutes, 1 AU (astronomical unit)
What are the first 5 letters of the Greek alphabet?
Alpha, Beta, Gamma, Delta, Epsilon
What is the density of water?
1.00 g/cm cubed
What is the density of a rock?
3.00 g/cm cubed
What is the density of gold?
20.0 g/cm cubed
Name 3 radioactive elements?
1) Uranium
2) Radium
3) Polonium
How long is the solar cycle of the Sun?
Solar cycle = Magnetic field. flips every 11 years
How long is the rotational period of the sun?
24 days at the equator. 35 days close to the top/bottom. called “Differential Rotation”
Who discovered the composition of the sun and in what year?
Cecilia Payne-Gaposchkin (1925)
What is the corona and what temperature is it?
Outer most layer of the suns atmosphere. Can be seen during a total solar eclipse.
2,000,000 K
What is the chromosphere of the sun and what temperature is it?
Lower region of the suns atmosphere. 10,000 K
What is the photosphere and what temperature is it?
“Visible surface” of the sun. 6,000 K. Where the Sun spots (solar granulation) happen
How long does it take a neutrino to get out of the sun?
2 seconds
How long does it take a photon to get out of the sun?
“Random walk” anywhere from 100,000 - 1,000,000 years
What are the 4 famous super novas and what years did they happen?
1054 - Crab
1572 - Tycho
1604 - Kepler
1987 - Large Magellanic Cloud
Who invented (discovered idk) the Bright line Dark line and Continuous star spectrum’s?
Bunsen and Kirchoff (1860ish)
Fraunhoffer- found the actual dark lines
What is frequency?
The number of waves that pass a fixed point in unit time
What is Lambda Max?
The wavelength at which a substance has its strongest photon absorption.
The highest point along the spectrums y-axis
What is Absolute brightness (Magnitude) M?
How bright a star appears at a distance of 10 pc
What is apparent brightness (Magnitude) m?
How bright a star appears from earth
Which type of stars show strong helium lines?
O & B stars
Which type of stars show strong hydrogen lines?
A stars
Which type of stars show strong molecule lines?
K & M stars
Name some binary systems?
Procyon A (main sequence)
-procyon B (white dwarf)
Sirius A (main sequence)
-sirius B (white dwarf)
Mizar and Alcor (6 star unit)
How long does it take Halley’s comet to orbit the sun?
76 years
What is “sublimation” and where would you see this term for astronomy?
(goes from a solid to a gas right away)
The solar winds “melt” the ice (sublimation) of a comet and the dirt trails behind
What is the temperature/ density of the center of the sun?
15,000,000 K
150 g/cm3
What is another name for hydrogen burning and what temperature is needed to do it?
Proton proton chain
10,000,000 K (fusion of protons)
What temperature is needed for helium burning?
100,000,000 K
What temperature is needed for C, N, O burning?
500,000,000 K
Density of the earth?
5.5 g/cm3
What is the brightest star (largest apparent mag from earth)?
Sirius A
Finish the sentence “The more luminous the star the………..”
And who discovered this?
the more luminous the star the HIGHER THE MASS.
Eddington discovered this.
What is the nearest star?
Proxima Centauri
What are brown dwarfs?
Bigger than a planet, smaller than a star.
“ Super planet or failed star “
Failed because doesn’t reach the 10 mil kelvin required to burn hydrogen
What are the 3 kinds of meterorites?
1) Stony
2) Metal (iron)
3) Stony (iron-type) RARE
How fast does Earth move?
30 km/s
Why do Cephied variable stars pulsate and how much can they change in size?
unequal pressure forces and gravity.
change of 20%
Which stars have longer lifetimes? (mass-lifetime relation)
Smaller mass = longer life
Bigger mass = shorter life
Composition of the suns surface?
75% H
24% He
1% metals
Composition of the suns center?
50% H (because its burning)
49% He
1% metals
What is another name for helium burning?
Triple alpha process
“helium flash”
What type of stars can burn CNO?
High mass stars (that reach 500mil K)
low mass stars cant
List some types of stars you would find in the instability strip?
Variable stars:
Cepheids
R R Lyrae
Z Z Ceti
What type of star is Trappist 1?
Low mass star (like proxima centauri).
It has 7 planets going around it
What is the Chandrasekhar limit?
When a star adds mass to the white dwarf it starts to shrink but the density increases.
The limit that a white dwarf can get to before turning into a super nova is 1.44mass of the sun.
“electron degenerate pressure”
What is a planetary nebula?
A glowing, expanding shell of ionized gas ejected from the low mass red giant. a white dwarf is left behind.
What type of spectrum is the moon?
Dark line (absorption)
Where would you find a continuous spectrum?
Glowing tungsten filament
what is an example of a black hole?
Cygnus X-1
Sagitarius A
What element does the H and K lines show?
Ionized calcium
Name of the observatory in victoria?
Dominion astrophysical observatory
Where is mount Palomar?
California
Which spectral type shows the strongest hydrogen lines?
A type stars
What type of lines are present in O type stars?
Ionized helium
What type of lines are present in B type stars ?
Neutral helium
