Midterm Flashcards

Question

Big dipper

Answer 1

part of the constellation Ursa Major (asterisms)

Answer 2

most prominent in winter months

Answer 3

Orion's hunting dog

Answer 4

the southern cross

Answer 5

measured north and south, in degrees from the equator (0) * North pole is +90, south pole is -90 * Los Angeles is 34 North latitude

Answer 6

Longitude is measured east and west, in degrees, from the prime meridian, also known as Greenwich meridian

Answer 7

Angles are measured in degrees, arcminutes and arcseconds

Answer 8

Point directly above you

Answer 9

Boundary where earth meets sky is the

Answer 10

is an imaginary semicircle stretching from due south to due north through the zenith

Answer 11

the angle that it appears to extend across the side

Answer 12

the angle separating them

Answer 13

* The Celestial sphere: an imaginary sphere centered at earth. In ancient times, the stars were thought to be on the surface of this sphere * Each night, the celestial spere appears to rotate counterclockwise around the north star

Answer 14

you will see stars apparently circling counterclockwise around the Celestial north pole

Answer 15

you will see stars apparently making a clockwise circle abut the southern horizon

Answer 16

you will see stars moving away from the horizon at an angle

Answer 17

when both hemispheres get the same amount of sunlight * The sun is the highest in the sky at summer solstice and lowest at winter solstice The length of nigh and day are equal at equinoxes

Answer 18

spring time equinox (march 21st)

Answer 19

Autumnal equinox: fall time equinox (september 21st)

Answer 20

Is the path the sun follows as it circles the celestial sphere once each year Because of the 23.5 tilt of Earth’s rotation axis, celestial equator at this same angle

Answer 21

Stars that always stay above the horizon

Answer 22

is 23 hours and 56 minutes long, and is the time it takes for stars to make a full circuit of the sky

Answer 23

divided the period of daylight into 10 hours, then added 1 hour for dawn and dusk. Night was divided into 12 hours Sun was used to keep time during the day

Answer 24

Greeks named the days of the week after the five known planets plus the sun and the moon Current names of the days include Germanic substitutions for names of some of the gods

Answer 25

The cycle of almost exactly 19 years which is common multiple of the sidereal year and synodic lunar month (26.5)

Answer 26

Occurs when the axis of the rotation of an oblate object is not vertical Gravitational pull of the sun and the moon tries to “correct” Earth’s tilted axis, causing the axis to precess in a circle with a period of 26,000 years

Answer 27

* Last we saw the far side happened: 1972 and this is the farthest we've gone * The far side of the moon is never visible * we are 250,000 miles away from the moon

Answer 28

* Synchronous rotation: Means that the moon always keeps the same face toward its parent planet * The moon executes one rotation around its axis during each revolution around the planet * tilted at 5 degrees, either above or below

Answer 29

Occurs when the far side of the moon is illuminated and the near side is not. This happens when the moon is between the sun and the earth rises at 6 am and sets at 6pm. The moon rises approx 50 minutes later each day, highest at the sky at noon

Answer 30

Occurs when the near side of the moon is illuminated and the far side is not. Happens when the moon is behind the earth rises at 6pm and sets at 6 am, highest at midnight

Answer 31

Occurs when the half of the near side is illuminated

Answer 32

* Full moon and new moon are 12 days apart * Phases changes every 24 days * Moon spends 12 hours being visible

Answer 33

rises at noon, setting at midnight, highest at 6pm

Answer 34

Third quarter: rises at midnight, setting at noon, highest at sky at 6 am

Answer 35

27.3 days (time it takes for the moon to go 360 degrees around the earth)

Answer 36

29.5 days long (time it takes from new moon to new moon)

Answer 37

related to both its linear diameter and its distance

Answer 38

* The sun appears approx as large in the sky as the moon (diameter: 0.50)

Answer 39

* lunar eclipse: Results when the moon passes through earth's shadow and occur only during a full moon Earth has an atmosphere, which deflects and diffuses sunlight

Answer 40

Occurs when the new moon blocks the earth's view of the sun Moon's distance from earth, and therefore its angular size, varies. When the moon is very far from earth, it cannot cover the solar disk only happens during a new moon

Answer 41

Penumbra: Partial shadow and umbra: total shadow

Answer 42

total lunar eclipse

Answer 43

Partial lunar eclipse

Answer 44

• Moon's distance from earth, and therefore its angular size, varies. When the moon is very far from earth, it cannot cover the solar disk • only happens during a new moon

Answer 45

* Co-Accreditation: Formed at the same time as earth from the solar nebula * Fission: Split off from each, probably due to high rotation * Capture: Formed elsewhere, gravitationally captured by earth * Impact: Formed from the impact of earth and another celestial body

Answer 46

* 6000-9000 years old, includes the prime numbers and crescent moon observations

Answer 47

* Correctly calculated the length of the year and times of sunrise and sunset throughout the year * Calculated the length of the synodic month more accurately than Ptolemy Mesopotamian Astronomy:

Answer 48

* Western astronomy originated in Mesopotamian

Answer 49

* Three major innovations. Developed a tradition of trying to understand nature without relying on supernatural * Used math to give precision to their idea * Saw the power of reasoning from observations

Answer 50

* Reality seen by humans is a distorted shadow of a perfect, ideal form * Perfection of heavens: most perfect form was the sphere, so the heavens must be made up of uniformly rotating perfect spheres

Answer 51

* Earth was the center of the universe * The sun, moon and each of the known planets had their own spheres * The stars were on the outermost sphere * Could not explain apparent retrograde motion of mars, jupiter, and saturn

Answer 52

* Earth made of four elements, heavens unchaging and made of fifth element, quintessence * Natural laws did not apply to the heavens * Natural state of matter was to be at rest * Earth was the center of the universe * Like elements attracted one-another

Answer 53

* Earth could not be moving as birds, clouds, etc would be left behind * The heavens were perfect and unchanging, so planetary orbits could not be noncircular * Stellar parallax had not been observed, so the earth could not orbit the sun

Answer 54

Atomists, beginning with Democritus, believed that atoms came together through random motions to form earth and heavy bodies, and could occur elsewhere in the universe Aristoltleism espoused the idea of an imperfect earth at the center of a perfect and unchanging heaven

Answer 55

Calculated relative sizes of the earth, the sun, and the moon Proposed heliocentric story Stars are extremely far away, hence no parallax Measured Earth-Moon and Earth-Sun distance With the measurement of angel MES the raito of EM and ES can be found (using trig)

Answer 56

Calculated the circumference of the earth (very accurately) 1 Stadion (egypitain) = 157km, 1 stadion (attic) = 185 km

Answer 57

Calculated positions and brightness of 1080 stars Discovered precession Invented epicycles to account for discrepancies in planetary orbits Made a cross stick, looking at two stars, you put the stick to ur eye and move it back and forth until it matches the distance between it. Also created a star chart The dimest star u can see with the lowest magnitude is 6 and the highest is 1

Answer 58

small circle on top of a big circle

Answer 59

Compiled a 13-volume summary of Greek astronomy Arabic translation is known as “Almagest” Refined Hipparchus model of deferents and epicycles

Answer 60

Planetary positions predicted based on uniform circular motion of planets around a stationary earth

Answer 61

Shield 1: Earth is the center of the universe Shield 2: The laws of nature are different on Earth and in the heavens Shield 3: Earth is “special” in the conditions on Earth don't exist elsewhere Shield 4: The universe can’t be very big

Answer 62

- Translated and absorbed astronomical knowledge from india, persia, greece, and rome - Invented algebra, algorithm - Invented lunar calender Completey redid ptolemy almagest - We still use many of their astronomical terms: Azimuth and nadir - First recorded observations of Andromeda galaxy and the large magellanic cloud - Computed the tilt of earth’s axis - Named many stars: Aldebaran, fomalhuat, alnitak, alnilam, mintaka -First detailed observations of supernovas in 1006 CE and 1054 CE - Argued for a beginning based on an actual infinite universe

Answer 63

Influenced by the work of Aristarchus and his own observations Proposed the sun as the center of the universe but also assumed perfect uniform circular orbits On the revolutions of the celestial spheres was published just after he died. Put forward that the 1sun not the earth is the center of the universe

Answer 64

Inner planets move faster, catching up and pasing slower planets Explained the appearance of mercury and venus as morning and evening stars

Answer 65

Had the most detailed and accurate observations of planetary motion Proposed the Tychonic model, which has the planets orbiting the sun and the sun (with the planets orbiting it) orbiting the earth Observed supernova of 1573 and by making parallax measurements refuted aristole’s claim of an unchanging “heavens”

Answer 66

Was hired to make sense of his very precise observations of planetary motion Was initially hung up on spherical symmetry of the solar system Finally realized planetary orbits were elliptical

Answer 67

First law: The orbit of each planet about the sun is an ellipse Second law: As a planet moves around the sun in its orbit, it sweeps out equal areas in equal times Third law: More distant planets obit the sun slower

Answer 68

A planet’s closet’s approach to the sun

Answer 69

The point at which a planet is farthest from the sun

Answer 70

a measure of how elongated is the ellipse and is a number between 1 and 0

Answer 71

Mission in life” to disprove aristole’s asserions about the universe Built the first telescope for observing the heavens (he was NOT the inventor of the telescope) Strike 1: Falling objects do so at the same rate, regardless of mass Objects in motion tend to stay in motion unless acted upon by an external force Strike 2: The imperfect sun Published in 1632, Dialogo avdocated for the copernican system over ptoleny’s Sun spots, first person to look at the sun and see the spots on the sun Strike 3: Stellar Parallax: First person to look at the milky way and see it is just a bunch of stars

Answer 72

Greek science had been mostly philosophy and conjecture based on the current cultural understanding of the world Kelper, galileo, and later newton based their assertions on observations and tried to answer why something happened

Answer 73

Modern science weeks explanations for an observed phenomenon A scientific model must make testable predictions about natural phenomena that would force us to revise the model if the predictions don't agree with the observations

Answer 74

Objectivty of science vs objectivity of individual scientists Personal bias can affect a scientist, subconsciously or deliberately affecting results Personal biases and errors are weeded out because of the number of people working in a scientific field, and testing of even the more outlandish ideas

Answer 75

A guess A conjecture Abstract thought Spectulation An assumption based on limited information or knowledge (A well-substantiated explanation of some aspect of the natural world; an ornagized system of accepted knowledge that applies in a variety of circumstances to explain an specific set of phenomena )(meaning of theory in science)

Answer 76

Co-Invented calculus Realized that the same gravitational force that made an apple fall from a tree was responsible for keeping the moon in orbit

Answer 77

Tells us how far we will travel in a given amount of time. Speed is measured in units of distance divided by time: miles per hour, kilometers per hour, meters per second

Answer 78

has the additional information of the direction of speed. Velocity is a “vector”

Answer 79

is the change of velocity. This could be a change in speed or in direction. Acceleration is measured in units of speed divided by the time

Answer 80

The measure of the amount of matter in an object. Units are kilograms or slugs

Answer 81

Is the product of mass and velocity. For the same speed, the higher the mass, the more momentum an object has

Answer 82

formally defined as a process that changed momentum. It takes force to accelerate an object or to slow it down. Units are newtons or pounds

Answer 83

The force of gravity on an object. On earth, your weight is your mass times the acceleration due to gravity. A person’s weight on the moon is 6 times less than that on earth, since the moon’s gravity is 6 times weaker

Answer 84

occurs when there isn’t any force to oppose your fall Objects in orbit around the earth are in a constant state of freefall

Answer 85

An Object tends to stay at rest and an object in uniform motion tends to stay in uniform motion unless acted upon by a net external force

Answer 86

Force = mass x acceleration: the more massive the object the more force is required

Answer 87

Every force, there is always an equal and opposite reaction force: a rocket takes off and accelerates by ejecting burning fuel in the opposite direction (for every action, there an equal opposite reaction)

Answer 88

Any two bodies in the universe attract each other with force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them. Double the distance force falls off by the factore the distance, half the distance, the force adds on by 4.

Answer 89

Energy is “conserved” quantity: it can’t appear from nowhere or disappear into “thin air”. The total amount of energy in the universe is constant Energy can be transferred from one object to another, or transformed/converted from one form into another Unites of energy is joles

Answer 90

The energy of motion. All moving objects have kinetic energy, the faster the object is, the more kinetic energy

Answer 91

Stored energy, which can be converted to kinetic or radiative energy. Energy that comes form you

Answer 92

Energy carried by light. This is the energy that warms the surface of the earth

Answer 93

A type of kinetic energy that measures the total kinetic energy of an object. Temperature is a measure of the average kinetic energy of an object

Answer 94

Our sun converts 600 million tons of hydrogen to 596 million tons of helium every secon. The “missing” 4 million tons is converted to raditive energy, producing 10^26 watts of power

Answer 95

Celsius, Fahrenheit, kelvin 100 degrees between freezing and boiling points of water in Kelvin and celsius 180 degrees between freezing and boiling points of water in fahrenheit scale

Answer 96

boiling poing 212 C , highest temp 134 C, freezing point of water 32 C, moon -280 C, absolutely zero -460 C

Answer 97

boiling point 100 C, highest temp 56.7 C, freezing point of water 0 C, moon -173 C, absolute 0 -460 C

Answer 98

boiling point 373.15 K, highest temp 330 K, freezing point of water 274.15 K , moon 100K , absolute zero 0 K

Answer 99

Many quantities are “conserved” during interactions including the amount of charge, energy, momentum, and angular momentum, unless there is an outside influence on the system

Answer 100

mass x velocity x radial distance Angular momentum keeps a planet roating and it is conserved

Answer 101

Objects in orbit have both kinetic and gravitational potential energy An object’s orbit can change only if it gains or loses orbital energy

Answer 102

Netwon found that kelper’s first two laws apply to all orbiting objects Ellipses aren’t the only possible orbits

Answer 103

Planets can be used to adjust a spacecraft’s orbit and accelerate it to higher speed

Answer 104

The moon exerts a gravitational pull on earth, which manifests itself in ocean tides Tides aren’t caused by the sun and the moon puling at earth from different sides. They’re causes by the difference in moon’s (or sun’s) gravity on the opposite sides of earth

Answer 105

The moon’s tidal force causes orbital “fiction”. Because of this, the tidal bugle is located sightly ahead of the earth-moon line

Answer 106

If the sun is along the earth-moon axis, then it contributes to the differential pull and makes a “spring tide”. Spring tides occur during the full moon and new moon If the sun is perpendicular to the earth-moon axis, it counteracts the different neap pull

Answer 107

Special theory of relativity (1905): There are no preferential reference frames, speed of light is finite and independent of the reference frame The general theory of relativity (1915): massive objects warp spacetime

Answer 108

Principle of relativity: The laws of physics are the same in every interior frame of reference

Answer 109

The effects of gravity and the effects of acceleration are exactly equivalent

Answer 110

Einstein’s theory of general relativity states that three-dimensional space and time combine into spacetime, and spacetime can be curved by the force of gravity All massive objects curve spacetime Spacetime curvature observed during the 1919 eclipse: the light of stars bent by the sun Time will go slower when you are near a black hole

Answer 111

Predicted by einstein’s theory of general relativity Carry gravitational energy away from a system the same way electromagnetic waves carry away energy by radiation First detected in February 2016

Answer 112

14th-century version: Entities should not be multiplied unnecessarily Modern version: When you have two competing theories that make exactly the same predictions, the simpler one is better

Answer 113

Light going through two narrow openings “interferes” to create patterns of dark and light bands

Answer 114

Light is an electromagnetic wave, made up of vibrating electric and magnetic fields Vibile light is only a small part of what we call the electromagnetic spectrum

Answer 115

distance between adjacent peaks of the wave

Answer 116

the number of peaks going by you every second (how often waves hit you) Wavelength x frequency = speed As wavelength goes up, the more frequency goes down

Answer 117

The EM spectrum includes radio waves, infrared and ultraviolet light, x-rays, and gamma rays Wavelength increases to the right and energy increases to the left When u go to blue the energy increases

Answer 118

Albert Einstein won the noble prize in Physics for his 1095 work on the photoelectric effect, which demonstrated that light sometimes behaves like a particle These packets are called photons

Answer 119

Discovered by Sir Frederick William Herschel in 1800 (he also discovered the planet Uranus in 1781) The human body radiates in the infrared of the EM spectrum

Answer 120

When matter is heated to high temperatures, it emits light. This is how a lightbulb works

Answer 121

Rocks placed in sunlight absorb the light and becomes hot

Answer 122

air, glass, and water all transmit sunlight (allow it to pass through)

Answer 123

mirrors reflect light

Answer 124

light goes through without being changed

Answer 125

Does not transmit light (absorbs it)

Answer 126

measure of what percentage of incident light is absorbed vs transmitted

Answer 127

Amount of reflection is called the albedo The darker a surface, the more sunlight it absorbed The lighter the surface, the less sunlight is absorbed What is not absorbed is reflected

Answer 128

Light-gathering power is proportional to the area of a mirror or lens Since telescope mirrors are approximately circular, light-gathering power is proportional to R^2

Answer 129

Resolving power is the ability to see detail, or to resolve two objects near one another

Answer 130

uses a primary lens to focus sunlight into an image that is magnified by a lens called an eyepiece The largest refracting telescope is built over 40” in diameter

Answer 131

uses a primary mirror to focus the light by reflecting, A small secondary mirror reflects the starlight back down through a hole in the middle of the primary lens to the eyepiece.

Answer 132

Uses one or more “guide” lasers to correct for atmospheric movement

Answer 133

“Sees” radio waves and can locate sources of radio waves from space

Answer 134

Radio waves are not blocked by clouds of gas and dust and allow us to peer inside the center of the milky way

Answer 135

The first reason: a lot of electromagnetic spectrum is blocked by our atmosphere Can view wavelengths blocked by earth's atmosphere Don’t have to deal with atmospheric disturbances Have much higher resolving power

Answer 136

JWST did a deep field image in 12 hours compared to 555 hours for Hubble

Answer 137

Water vapor was detected in the atmosphere of WASP-96b, a hot Jupiter in a very tight orbit around its star

Answer 138

Matter made up of atoms (ancient greek concept with a new meaning) Each element has a unique atom that is a combination of neutrons and protons in the nucleus surrounded by a cloud of electrons Protons and neutrons are made up of there quarks each

Answer 139

Proton carry positive charge and electrons have a negative charge equal to the protons charges. Netruons are neutral

Answer 140

The elements are distinguished by the number of protons (called atomic number) in the nucleus of their atoms Atomic mass: total of protons and neutrons in the nucleus What makes an element unique is the number of protons

Answer 141

Atoms of same element with extra neutrons

Answer 142

When two or more atoms bond together, a molecule is formed

Answer 143

Simplest organic molecules are combinations of carbon and hydrogen, and sometimes oxygen: methane is one carbon atom bonded to 4 hydrogen atoms Any molecule that contains carbon that id called “orangic” molecule

Answer 144

characterized by structural rigidity and resistance to deformation

Answer 145

a fluid whose shape determined by container it fills

Answer 146

a collection of atoms and/or molecules without a definite shape or volume that are in more or less random motion

Answer 147

a partial or fully ionized gas in which some or all of the electrons aren’t bound to atoms

Answer 148

the closet the electron can get to a proton

Answer 149

Matter leaves its “fingerprints” on the EM spectrum We can identify each element found in a star by the emission spectrum of that element. A spectrograph allows us to examine the spectrum of visible light for “telltale” signs

Answer 150

“Missing” wavelengths tell us about the gas cloud

Answer 151

Specific wavelengths continued

Answer 152

An uninterrupted rainbow of wavelengths

Answer 153

All waves undergo the doppler effect Drop in pitch when a train passed the person In front: longer wavelength, sound lower pitches. Behind: short wavelength, sound higher pitch

Answer 154

Objects moving away are “redshifted”, meaning the spectral lines have moved toward the red end spectrum Objects moving towards usc are “blue-shifted” meaning the spectral line have moved towards the blue end of the spectrum The longer the shift, the faster the object goes

Answer 155

Edge of the star rotating towards us is blueshifted Edge of the star rotating away is redshifted The faster the rotation, the broader the spectral lines

Answer 156

Objects moving away are “redshifted,” meaning the spectral lines have moved toward the red end of the spectrum. Objects moving towards us are “blueshifted”, meaning the spectral lines have moved toward the blue end of the spectrum.

Answer 157

All spectra we’ve looked at have been very precise and sharp

Answer 158

If atoms/molecules in gas cloud are moving rapidly (i.e., the cloud has a high temperature), then each emission will be Doppler shifted in a random direction, resulting in an overall broadening of the spectral line

Answer 159

All objects in the universe radiate energy. The hotter they are, the more energy they radiate The surface of Betelgeuse is 5840, it radiates light peaked at red. Rigel has a surface temperature of 19,000 °F (11,000 K) and radiates light in the blue portion of the EM spectrum.

Answer 160

Each square meter of a hotter object’s surface emits more light at all wavelengths

Answer 161

Hotter objects emit photons with a higher average energy

Midterm Flashcards

(185 cards)