Astronomy MID-TERM

Aristotle (Geocentric)

• Experiment and reason

• discovered the five elements

• round earth experiments (Gravity, constellations, lunar eclipse)

• Moon phases

Aristarchus (Heliocentric)

• 1,700 years before copernicus’ discoveries

• sun,moon, sizes and distance from earth

• stars, suns and parallax and the earth’s rotation

Eratosthenes (Geocentric)

• invented geography

• measured size and tilt of earth

• alexandria — syene (Aswan)

Hipparchus (Geocentric)

• Developed trigonometry

• created greatest star maps to date

• discovered precession

• created stellar magnitude system

• developed reliable methods for predicting eclipse

Ptolemy (Geocentric)

• Deferent and Epicycle

• Equant

• Retrograde motion

Copernicus (Heliocentric)

• Planetary configuration

• conjuctions (Plains, Inferior, Superior)

• Oppositions

• Quadrature

• Elongation

• Transit

• Twilight Zone

• Retrograde Motion

Tycho (Geocentric)

• Save the geocentric

• tychonic planetary system

• supernova 1572

• comet 1577

Kepler (Helliocentric)

• Three laws of planetary motion

• law of eclipses

Kepler’s laws of planetary motion

• planets travel around the sun in eclipses with the sun at one focus

• the straight line joining the the sun and the planet sweeps out equal areas in equal times

• the straight of siderial period of planet is in direct proportion to the cube of the semimajor axis (Distance to the sun) of its orbit

Newton’s Law of Motion

1. Inertia - a body at rest styes at rest or in motion in motion in a straight line unless acted upon by an outside force

2. Acceleration - A change in motion is directly proportional to the force acting on it and in the direction of that force

3. (Action/Reactions) To every action there is an equal and opposite reaction

Newton’s law of gravitational

Between any two objects anywhere in space there exists a force of attraction that is in direct

Galileo

• Pendulum

• Objects Fall at Same rate due to earth’s central force (Gravity)

• Inertia ( foundations for newtons laws )

• light speed

Galileo’s moon observations

• moon

• sun

• jupiter

• venus

• saturn

• milky way

Isaac Newton (Heliocentric)

• Calculus

• Light (Spectrum)

• Reflecting telescope

• three laws of motion (Inertia, acceleration, action/reaction)

• universal law of gravitation

Halley (Heliocentric)

• Diving bell

• Mathematically verified Newton’s Theory of gravity

• Discovered proper motion of Stars

• Discovered some comets are periodic

Heliocentric

theorizes that the sun is the center of the solar system

Geocentric

argues that the earth is the center of the solar system

Lippershey

“Invented the telescope” was the first to patent the tool

Cassegrain

Lauren Cassegrain invented the cassegrain reflector

Schmidt

Also known as the schmidt telescope

Herschel

• discovered infrared

• discovered uranus

Huygens

Christian Huygens discovered the light waves theory, he believes that light travels like a wave

Maxwell

came up with a different Ideal and liked newtons idea of light traveling was huscular — accepted the idea of hilance aka light being an idea

Romer

discovered that light takes time to travel

Light travels 136,400 miles per second

Michelson

a physicist and does astronomy from australia, set up an experiment for the speed of light

• invented the eight sied mirror rotating

• 186,282 miles per second for the speed of light

speed of light (mps)

186,282 miles per second

• 5,800,000,000,000 miles

jansky

Discovered radio astronomy, invented the radio telescope

Reber

reber had mapped the radio structure of our galaxy and discovered radio raves outside of our galaxy

Einstein

• created what we know as photons which is particles of energy

• concluded that night is not just a wave or a particle but a particle known as a waveacle of energy

• gravity waves

Gravity

Galileo was the first to discover the effects of gravity

Altitude

the apparent height, is the angle between the object and the observer’s local horizion

Azimuth

when an angle is between 0 and 90 degrees and is measured from true north and increasingly upwards

Degree’s

Hours

Earth’s tilt

Earth is tilted 23.5’

Latitude

up and down

longitude

horizontally

ROYGBIV

Red, orange, yellow, green, blue, indigo, violet

Precession

• discovered by hipparchus

Zenith

the high point - the very top of the sky

Nadir

the lowest point of the fortune

Meridian

a line of longitude that we say is the beginning

North Pole

the northermost point on the earth

South Pole

below the equator

Equator

is the center of the earth

Celestial Pole

the equator of the sky

tropic of cancer

lies at the 23rd 26’33 23.439 north of the equator and marks the most northerly latitude at which the sun can appear directly at noon

tropics of capricorn

23rd 26’22 (23.5) degrees

Antartic circle

66.5 degrees

Arctic circle

66 degrees and 33’ north of the equator

International Date Line

in the pacific ocean and it is to keep things in order and separates the time and day

Right Ascension (Longitude)

hours, minutes, seconds *due to changing rotation

Declination (latitude)

degrees, minutes, secons

Ecliptic

the time of a planet going around a sun

planetary configuration

especially significant apparent position of a planet

syzygy

the alignment of inferior and superior planets

Retrograde motion

was on the epicycle, when a fast planet passes a slow planet, the slower planet will appear to be moving backwards

Inferior conjunction

occurs when the planets are approximately between Earth and the sun

Superior Conjunction

when the inferior planets is in alignment or opposite side of the earth

Conjuction

an apparent

lunar phases

• new moon

• waxing crescent

• first quarter

• waxing gibbous

• full moon

• wanning gibbous

• last quarter

• waning crescent

• new moon

inferior planet

mercury, venus

syzygy

the alignment of inferior and superior planets

Retrograde motion

was on the epicycle, when a fast planet passes a slow planet, the slower planet will appear to be moving backwards

Inferior conjunction

occurs when the planets are approximately between Earth and the sun

Superior Conjunction

when the inferior planets is in alignment or opposite side of the earth

Quadrature

between the sun the earth and the planet you have a right angle that forms, it can be east or west

Jovian Planets

Gas giants, a group of 4 planets that are in the solar system and they compromise the outer planets

Terrestial planets

they have a compact, rocky surface, like earths terra firma

Insolation

is the amount of solar radiation recieved on a given surface in a given time period.

Equinox

23rd of september

the period of day-time is equal to the period of nighttime

daylight savings

Solstice

the point where the sun appears to reach the highest or the lowest point in the sky for years

seasons

fall,winter,spring,summer the suns direct rays

• so when the north pole tilts towards the sun it is summer in the northern hemisphere

solar eclipses

only occur if there is perfect alignment and szyygy

lunar eclipses

occur when the moon moves into its shadow - last 6-7 minutes

synchronous rotation

describes the rotation of an object that always shows the same face to an object that is orbitting because its rotation period and orbital period are the same

synotic

the perfect alignment from where we began and where we land 29 and half degrees

sidereal period

360 degrees of motion - perfect circle

— 27 and 1/3 says but you arent in a straight line and need extra time and 29 and a half days to get back

deferent

created so that the planet would go around the epicycle as thew epicycle is going around the deferent which is centered around the equate

epicycle

geometric model used to explain the variations in speed and direction of the motion of the moon and the sun and the planets — in a circular motion

orbit

regular repeating path that one object in space takes around another one

greatest elongation

when a planet appears farthest from the sun as viewed from the earth

perigee

the point of the closest approach to the earth

— moving at its maximum speed

synchronous rotation

describes the rotation of an object that always shows the same face to an object that is orbitting because its rotation period and orbital period are the same

synotic

the perfect alignment from where we began and where we land 29 and half degrees

plutoids

named after plutos, objects just like pluto in structure — just like pluto in structure

Perihelion

the close point between the earth and the sun

aphelion

far point from the sun and the sun looks a lot smaller in july we were 4 million miles away

orbit

regular repeating path that one object in space takes around another one

TNO‘s

Any celestial object in our solar system whose orbit lies beyond neptune, including pluto

greatest elongation

when a planet appears farthest from the sun as viewed from the earth

comets

objects with a large trail there are comets that form

angstroms

extremely small units only 1 centimeter

red light

long wavelength

blue light

shorter wavelength

speed of light

wavelength x frequency = the speed of light

wavelength

the distance between succesive crests of a wave especially points in a sound wave or electromagnetic wave

Refracting telescope

uses the front of the lens, objective lens in the front end

reflector telescope

uses a mirror

cassegrain

cassegram designed for camera work and was made for the design of reflecting telescopes