Group 1: Leo 1, Large Megellanic Cloud
Group 2: M51, NGC 6946, M101
Group 3: Arp 252, NGC 1365
Group 4: M65, M81, M109
Group 5: NGC 4650a, NGC 253, M104, NGC 4565
Group 6: M32, M87, M59
Group 7: NGC 1073, M82, NGC 2146
By Actual Category:
Elliptical Galaxies: M59, M32, M87,
Starburst Galaxies: M82, NGC 253
Dwarf Galaxy: Leo 1
Spiral Galaxies: M51, NGC 6946, M101, M65, M81, M104, NGC 4565
Barred Spiral Galaxies: M109, NGC 1365, NGC 1073, NGC 2146
Irregular Galaxy: LMC (Large Megellanic Cloud)
Interacting Galaxy Pair: Arp 252
Ring Galaxy: NGC4650a
Reflection: Sorting galaxies can be tough... if you go by color, size, shape, makeup, other characteristics.. it just depends on what you arbitrarily choose. We went through them and divided them based on appearance, then later went back and actually looked up what each of the galaxy types were, coming up with the second list. Classification is a good tool in science, and this is no different. Knowing what a type of galaxy is can give us clues as to how it's going to react/chance/evolve (etc).
WEIGHING A GALAXY:
1. Apply this equation to three of the planets in our solar system, given in the table below.
Mass of Earth: 200kg
Mass of Jupiter: 200kg
Mass of Neptune: 196 kg
The masses are all relatively the same.
The mass of the sun would be about 200kg too?
2. DISTANCE: 5.0 - 1.55 x 10^17 km VELOCITY: 95.0 km/s MASS: 2,097,263,869 kg mass.
DISTANCE: 10.0 - 3.1 x 10^17 km VELOCITY: 110.0 km/s MASS: 5,623,688,156 kg mass.
DISTANCE: 15.0 - 4.65 x 10^17 km VELOCITY: 110.0 km/s MASS: 8,435,531,134 kg mass.
What do you notice about the values of the mass as the distance increases?
They get considerably larger.
Can you explain this?
Distance is directly related to mass.
What would you conclude the mass of the galaxy to be?
More than 1,000 solar units.
How much more massive is this galaxy than our sun?
A lot more - not even comparable. See above answer.
Reflection: I wouldn't call this one of the most useful labs, but it does help in clarifying how scientists go about their estimates of distance/mass/etc. I'd say math is neccessary for the survival of science. xD I appreciate math. A lot more.