11 - Cosmic Scales and Galactic Islands of Stars

Question 1

an expression of distance across a visible area

Answer 1

field of view

Question 2

measures large sums and expresses as powers of 10
(ex. 9.0 x 1010 or 105 = 100,000)

Answer 2

scientific notation

Question 3

150 000 000 km or 1.5 x 10*8km, average distance earth to sun

Answer 3

Astronomical Unit (AU)

Question 4

distance light travels in a year, which is 63,000 AU or 10*13km

Answer 4

Light Year (LY)

Question 5

10*3

Answer 5

kilo = 1000

Question 6

10*6

Answer 6

mega = 1 000 000 (million)

Question 7

10*9

Answer 7

giga = 1 000 000 000 (billion)

Question 8

what do you call a galaxy group?

Answer 8

cluster

Question 9

what do you call a cluster of clusters of galaxies?

Answer 9

supercluster

Question 10

the universe is approximately how old? (everything we can see)

Answer 10

13.8 Giga Years Old
(13.8 billion)

Question 11

long cloudy masses of superclusters outlining near empty voids is called

Answer 11

filaments of walls

Question 12

matter that’s confined to galaxy plane of rotation (stars, open clusters, gas, dust)

Answer 12

disk components

Question 13

contains lots of gas, site of most star formation, lit by recently formed blue stars

Answer 13

disk

Question 14

long curves from centre to edge of bright stars, star clusters, gas, dust

Answer 14

spiral arms

Question 15

matter scattered in roughly spherical distribution around central point

Answer 15

spherical component

Question 16

dense cloud of stars that surround galaxy center, old cool stars, redder, little dust

Answer 16

central bulge

Question 17

spherical region, thin scattering of stars, very little gas/dust so mostly old stars, cool giants, or dim lower-main sequence

Answer 17

halo

Question 18

graph of orbital velocity vs radius in disk of galaxy

Answer 18

rotation curve

Question 19

low-density extension of halo, of dark matter, most not producing light

Answer 19

dark halo

Question 20

non luminous matter suggested by its gravitational influence

Answer 20

dark matter

Question 21

this population of stars are rich in “metals” (all atoms heavier than helium) and is located in the disk, older and have circular orbits

Answer 21

population 1 stars

Question 22

this population of stars are located in halo, globular clusters, and central bulge, orbits are random, they’re young.

Answer 22

population II stars

Question 23

What are the three types of galaxies in the galaxy classification system?

Answer 23

1. Elliptical Galaxy: round or elliptical with balls of stars, few or no bright stars
2. Spiral Galaxy: about 35% of galaxies, spiral arms, halo stars, hot O and B stars (blue arms with yellow core)
3. Irregular Galaxy: about 25% with no obvious bulge/arms, any shape