Cumulative Exam

Question 1

declination

Answer 1

the angular distance of a point north or south of the celestial equator

Question 1

right ascension

Answer 1

the celestial equivalent of longitude

Question 2

azimuth

Answer 2

the angle between North, measured clockwise around the observer’s horizon, and a celestial body

Question 3

altitude

Answer 3

the angle between the horizon and a point in the sky

Question 4

longitude

Answer 4

is a geographic coordinate that specifies the east–west position of a point on the surface of the Earth, or another celestial body

Question 5

latitude

Answer 5

the angle between the plane of the earth’s equator and the plumb line (direction of gravity) at a given point on the earth’s surface

Question 6

horizon coordinate system

Answer 6

a celestial coordinate system that uses altitude and azimuth as coordinates to find objects in the sky and determine their positioning

Question 7

equatorial coordinate system

Answer 7

a celestial coordinate system that uses two measurements, right ascension and declination, to track the positions of objects in the sky

Question 8

zenith

Answer 8

the point on the celestial sphere that is directly above an observer

Question 9

The location of zero latitude is the

Answer 9

equator

Question 10

The zero point for longitude is the

Answer 10

prime meridian

Question 11

The point with the highest altitude is the

Answer 11

zenith

Question 12

waxing

Answer 12

when the percent illumination of the moon is increasing

Question 13

waning

Answer 13

when the percent illumination of the moon is decreasing

Question 14

gibbous

Answer 14

when the moon is more than 50% illuminated

Question 15

crescent

Answer 15

when the moon is less than 50% illuminated

Question 16

the horizon plane

Answer 16

the plane that separates the blocked and visible portions of space

Question 16

nadir

Answer 16

point directly below the observer

Question 16

celestial meridian

Answer 16

the imaginary line that runs in the sky from the north to the south

Question 17

geocentric theory

Answer 17

everything revolves around the earth

Question 18

heliocentric theory

Answer 18

everything revolves around the sun

Question 19

parallax

Answer 19

the shift in angle that occurs when a nearby object is seen against a distant backdrop from two different perspectives

Question 20

sidereal period

Answer 20

the time it takes a planet to orbit the sun once

Question 21

synodic period

Answer 21

the time it takes a planet to move all the way through our sky and end up back in the same place in our sky;
the time it takes for a planet to make a complete cycle of elongation configurations

Question 22

elongation

Answer 22

the angle between the sun and a planet as seen by an observer on earth

Question 23

inferior planets

Answer 23

planets that are closer to the sun than the earth; will never have an elongation of 180°

Question 24

superior planets

Answer 24

planets that are farther away from the sun than the earth; can have any elongation value between 0° and 180°

Question 25

the greatest elongation

Answer 25

the maximum angle that ever occurs between the sun and an inferior planet; depends on the planet's distance from the sun

Question 26

inferior conjunction

Answer 26

when the planet is between the sun and the earth (inferior planets)

Question 27

superior conjunction

Answer 27

when the planet is on the other side of the sun as seen from earth (inferior planets)

Question 28

conjunction

Answer 28

when a superior planet has an elongation of 0°

Question 29

opposition

Answer 29

an elongation of 180° is called opposition (superior planets)

Question 30

quadrature

Answer 30

when the planet has an elongation of 90° (superior planets)

Question 31

perihelion

Answer 31

the point at which a planet is closest to the sun during an elliptical orbit; moves fastest at this period

Question 32

aphelion

Answer 32

the point at which a planet is farthest from the sun during an elliptical orbit; moves slowest at this period

Question 33

Newton's 3 laws of motion

Answer 33

An object stays at rest or in constant motion unless an unbalanced force acts on it. An object responds to a force with an acceleration that is proportional to the force and in the direction of the force, and inversely proportional to the mass. For every force on an object, there is an equal and opposite reaction.

Question 34

Kirchhoff's 3 laws of radiation

Answer 34

A gas, or a sufficiently heated solid, will glow with a smooth, continuous spectrum, or continuum. A hot gas will produce only certain bright and narrow wavelengths, called emission lines. Each element emits a characteristic set of emission lines. A cool gas, if placed between the observer and a hot continuous-spectrum source, absorbs certain wavelengths, causing narrow absorption lines in the observed spectrum.

Question 35

What are the 2 main components of the moon?

Answer 35

the dark maria and the light highlands

Question 36

light highlands

Answer 36

the original lunar crust, composed of calcium and aluminum-rich feldspar

Question 37

scarp

Answer 37

a raised ridge on the surface of Mercury

Question 38

regolith

Answer 38

pulverized rock that covers the Moon as a fine dust

Question 39

ray

Answer 39

a bright line emanating outward from craters

Question 40

maria

Answer 40

smooth dark regions on the Moon where lava once flowed

Question 41

Caloris Basin

Answer 41

a very large impact crater on Mercury

Question 42

Olympus Mons

Answer 42

the largest mountain ever discovered, located on Mars

Question 43

Mauna Kea

Answer 43

the largest mountain on Earth (as measured from the sea floor)

Question 44

What are the gas giant planets?

Answer 44

jupiter, saturn, uranus, neptune

Question 45

redshift

Answer 45

to longer wavelengths; the source is moving away from the observer

Question 46

blueshift

Answer 46

to shorter wavelengths; the source is moving towards the observer

Question 47

what can we learn by analyzing starlight?

Answer 47

a star's temperature (peak wavelength of the spectral curve), chemical composition (dips in the spectral curve OR lines in the absorption spectrum), and motion (doppler shift)

Question 48

corona

Answer 48

the sun's atmosphere

Question 49

photosphere

Answer 49

visible part of the sun

Question 50

luminosity

Answer 50

the total of all light in all wavelengths coming from an object

Question 51

What are 3 types of compact objects?

Answer 51

white dwarfs neutron stars black holes

Question 52

disk

Answer 52

the flattened distribution of stars that appears as a band of light in the night sky that gives the Milky Way its name; many of the stars in the disk are young and blue and gathered into groups (e.g. star forming regions and open clusters); where the Sun is located

Question 53

bulge

Answer 53

toward the center of our galaxy is a concentration of generally old and red stars called the galactic bulge

Question 54

halo

Answer 54

the disk is surrounded by a spherical swarm of stars and groups of stars collectively called the halo; halo stars are generally old and red, and the groups in this region are referred to as Globular clusters

Question 55

How many stars are in the Milky Way Galaxy?

Answer 55

300 billion

Question 56

interstellar material

Answer 56

gas (that is, atoms and molecules), microscopic dust grains, and possibly larger objects

Question 57

how many interstellar molecules have been cateloged?

Answer 57

more than 130; the most important in astrophysical processes are molecular hydrogen (H2) and carbon monoxide (CO)

Question 58

the building blocks of life

Answer 58

carbon, hydrogen, oxygen, and nitrogen

Question 59

what are interstellar grains made of?

Answer 59

silicates, metals, and ices; though the tiny dust grains are rare compared to hydrogen atom, they have a big effect on starlight

Question 60

velocity dispersion

Answer 60

the spread or scatter in motions in any gravitational system

Question 61

how much of the mass of each galaxy is dark matter?

Answer 61

80 to 90%

Question 62

elliptical galaxy

Answer 62

looks like a glowing ball of light

Question 63

spiral galaxy

Answer 63

have clear spiral arms in a disk and a bright bulging core in the center; can often see streaks of dust clouds within a galaxy’s spiral arms

Question 64

Hubble found three major types of galaxies in his study of the regions of space beyond the Milky Way:

Answer 64

spiral, elliptical, and irregular galaxies