Chapter 16 Part A ( up to 413)(Karly's 15)

Question 1

Types of Galaxies

Answer 1

Irregular, Spiral, Elliptical

Question 2

of the three galaxies these are redder

Answer 2

Elliptical

Question 3

contain more cool gas and dust and interspersed with hot ionized gas

Answer 3

Spiral

Question 4

What causes the different colours of galaxies

Answer 4

Types of stars

Question 5

Why do Spiral and Elliptical galaxies appear white

Answer 5

have all kinds of stars

Question 6

A dwarf galaxy has less than

Answer 6

less than a billion stars

Question 7

A giant galaxy has more than

Answer 7

a trillion stars

Question 8

Why is the halo of a spiral galaxy hard to see

Answer 8

because halo stars are dim and spread over a large volume of space

Question 9

Example of a spiral galaxy

Answer 9

Milky way

Question 10

Disk stars include stars of ..

Answer 10

all ages and masses

Question 11

Halo stars are

Answer 11

old and low in mass

Question 12

Galaxy disks always contain_________medium but the proportions of _______,atomic and _____________gas differ from galaxy to galaxy

Answer 12

Galaxy disks always containINTERSTELLAR medium but the proportions of MOLECULAR ,atomic and IONIZED gas differ from galaxy to galaxy

Question 13

The halo component of the spiral galaxy includes

Answer 13

the halo and central bulge

Question 14

Major difference between elliptical and spiral galaxy

Answer 14

elliptical do not have a disk

Question 15

Do Elliptical Galaxies have a lot of cool gas?

Answer 15

nope - that is usually in disks where stars are a forming

Question 16

Most common type of Galaxies in the universe

Answer 16

dwarf spheroidal galaxies

Question 17

classification for larger magellanic clouds or galaxies which appear to be in dissarray

Answer 17

irregular galaxies

Question 18

irregular galaxies are most common…This tells us they were more common when..

Answer 18

among distant galaxies and as such were more common when the universe was younger

Question 19

Elliptical Galaxies are noted with an E and a corresponding number. The larger the number, the…
An E0 galaxy is a-

Answer 19

• the flatter the elliptical galaxy

- sphere

Question 20

SB denotes what kind of Galaxy

Answer 20

Spherical- barred galaxy

Question 21

Sa denotes a….

SBc denotes a…

Answer 21

Spherical galaxy with a large bulge …lol

Spherical barred galaxy with a smaller bulge than the Sa. llololollol

Question 22

Spiral Galaxies tend to congregate in small…

Answer 22

groups of a few dozen

Question 23

Elliptical Galaxies tend to be found in …..which may contain

Answer 23

clusters which may contain 100’s of thousands of galaxies

Question 24

Why do galaxies differ?

Answer 24

Spin, Density, Collisions

Question 25

Why would spin alter the shape of a galaxy?

Answer 25

amount of angular momentum of a protogalactic cloud could determine size of resulting disk

Question 26

Why would Density of the protogalactic cloud impact shape of galaxy?

Answer 26

Elliptical galaxies could come from dense protogalactic clouds that were able to cool and form stars before gas settled into a disk.

Question 27

What may explain why elliptical galaxy's are found in large clusters?

Answer 27

evidence of a supercomputer's representation of two spiral galaxies colliding and formatting an elliptical galaxy

Question 28

Hubble’s constant tells | us age of universe because

Answer 28

it relates velocities and distances of all galaxies

Question 29

The cosmological horizon or maximum look back time is

Answer 29

14 billion years

Question 30

1. If the center of a galaxy is unusually bright (~100-1000 LMWG) we call it an... 2.The most luminous are called...

Answer 30

-active galactic nucleus (AGN). -Quasars are the most luminous examples of AGNs!

Question 31

Parallax is the _______ ________ in a star's position as __________ orbits _ _______. Measuring distance using Parallax requires knowing the ....

Answer 31

Parallax is the APPARENT SHIFT in a star's position as EARTH orbits THE SUN.Measuring distance using Parallax requires knowing the .PRECISE SUN-EARTH DISTANCE OR AU.

Question 32

Speed of radio waves

Answer 32

speed of light

Question 33

We can determine distance by measuring....and applying the inverse square law for light

Answer 33

We can measure distance by measuring the APPARENT BRIGHTNESS OF AN OBJECT WHOSE LUMINOSITY WE ALREADY KNOW and applying the inverse square law for light

Question 34

Our sun is a main-sequence star with a spectral type of

Answer 34

G2

Question 35

a standard candle is a

Answer 35

light source of a known luminosity

Question 36

The more certain we are of about a objects true luminosity, the more certain we are of

Answer 36

its distance

Question 37

Main sequence fitting is one of the most important techniques for measuring distance. It relies on..

Answer 37

comparisons of main sequence stars on the HR Diagram that we already know the distance of, to clusters we dont

Question 38

The most useful standard candles are ______ _______ ________because we can determine a Cepheid 's luminosity from the ...

Answer 38

Cepheid Variable Stars because we can determine a Cepheid 's luminosity from the period between its peaks of brightness

Question 39

White dwarf supernovae are useful for measuring___________ distances because they are __________and all have the same ______ _________.

Answer 39

White dwarf supernovae are useful for measuring LARGE distances because they are BRIGHT and all have the same PEAK LUMINOSITY.

Question 40

When Hubble proved the Andromeda Galaxy WAS NOT inside the Milky way (using _______ _______) he proved that the Milky way was...

Answer 40

When Hubble proved the Andromeda Galaxy WAS NOT inside the Milky way (using CEPHEID VARIABLES) he proved that the Milky way was...merely one of many galaxies

Question 41

A galaxy's red shift tells us...

Answer 41

how fast it is moving away from us

Question 42

The relationship between __________ and __________ tells us the universe is expanding

Answer 42

The relationship between REDSHIFT and DISTANCE tells us the universe is expanding

Question 43

CHAPTER 15 IS

Answer 43

HELLA LONG... : ( I'MA MAKE IT TWO SECTIONS