6th Grade Unit 1 Test The Solar System

Universe

space and all the energy and matter in it made up of 3 ingredients: matter, energy, space

Solar System

collection of large and small bodies that orbit a star

Planet

spherical body that orbits a star

Star

large celestial body; made of gas; emits light

parallax

apparent shift in an object when viewed at from different location

nuclear fusion

fusion of lighter elements into heavier
ex: hydrogen to helium

galaxy

large collection of stars, dust, and gas

nebula

large cloud of dust and gas

light year

unit of measure which is the distance light travels in an earth year

heliocentric

model of solar system in which the sun is the center and all planets orbit

geocentric

model of solar system in which the sun and all planets revolve around the earth

supernova

gigantic explosion from a high mass start; throws its outer layers into space

What makes up the Universe?

8 planets, our star (sun), 100 billion+ galaxies, 3-d web

Earth

atmosphere allows for water cycle; water is essential for life; plants produce oxygen; animal life needs oxygen; thin layer of ozone gas; ozone absorbs radiation; some gasses keep earth warm enough
3rd planet from sun

Sun

medium sized star; earth's star the sun's gravity keeps the planets in orbit

Solar System

8 planets, moons, comets, meteoroids, asteroids, comets; part of the Milky Way galaxy

Terrestrial planets

Mercury, Venus, Earth, Mars (rocky, dense, small)

Gas Giants

Jupiter, Saturn, Uranus, Neptune (thick, gaseous, rocky core)

Stars

mostly hydrogen & helium; energy produced in core; energy escapes as visible light; vary in size

Galaxies

large collection of stars, gas, dust held by gravity

Types of Galaxies

spiral, elliptical, irregular

Nebula

large cloud of dust & gas; most stars form here

Supernova

gigantic explosion from high mass star

Types of Nebula

emission nebulae-red glow-Orion reflection nebulae-blue glow-reflect light from other stars dark nebulae-dark-block light of stars

heliocentric

earth and planets orbit sun

geocentric

sun and planets orbit earth (older theory)

electromagnetic spectrum

different wavelengths and frequencies in a spectrum

FYI

Stars twinkle, planets don't.
Energy comes in the form of light and/or heat.
Big Bang Theory - space, time, matter, energy released from the primeval atom.
8 minutes for sunlight to reach Earth.
Gravity is the weakest force in the universe.
EM Spectrum gives us five kinds of information - MDPCT.
Nebulas are nurseries for new stars.
Universal address: Earth, Solar System, Orion Arm of the Milky Way, Local Group, Virgo Supercluster, Laniakea Supercluster, Universe
5 types of small objects - DCMAK.

spectrum

continuous range of a single wavelength

Einstein

developed theory of relativity-time and space space and time curve

Hubble

Hubble space telescope is named after him showed evidence that universe is expanding

redshift

apparent shift in an object toward longer wavelengths (moving further away from the observer)

Big Bang Theory

the universe began with an expansion 13-15 billion yrs ago

BBT evidence

abundance of light elements redshift of galaxies cosmic microwave background

Kepler's first law

objects follow an elliptical path around the sun

aphelion

point that is farthest from the sun; planets at slower speed

perihelion

point that is closest to the sun; planets at faster speed

Kepler's second law

as a planet moves around its orbit, it sweeps out in equal areas at equal times

Kepler's Third Law

orbital period squared is equal to the planet's average distance to the sun cubed

Newton

first scientist to explain gravity

Law of Universal Gravitation

all object attract each other through gravitational force
force of gravity between objects increases as mass increases
distance increases between objects when force of gravity decreases

centripetal force equation

inward force that causes an object to move in a circular path

inertia

The tendency of an object to resist a change in motion and stay in a straight line

How did the solar system form?

cloud of gas and dust collapsed and began to spin as the rotation increased, the speed flattened the cloud this became a protostellar disk
friction heated the disk and the helium and hydrogen fusion released a lot of energy
that caused outward pressure and a star was born-the sun

planetesimal formation

as the sun was forming, dust collided and stuck together

Mercury

lots of craters, volcanic rock, iron core, extreme temps, smallest planet in solar system

Venus

sufuric acid rain, earth's twin, craters and volcanoes, very hot

Mars

4th planet from sun, thin atmosphere, mostly dark volcanic rock, red color from iron dust, large volcanoes

Gas giants

Jupiter, Saturn, Uranus, Neptune

Jupiter

5th planet from sun, largest, highest surface gravity, fastest rotation, high winds, storms, large moons, icy surface

Saturn

6th from sun, planetary ring (materials of particles that circle the planet-its gaps have moons)

Uranus

7th from sun, composed of hydrogen & helium, methane in atmosphere, blue-green color, tilted axis, long seasons

Neptune

8th planet from sun, blue ice giant, composed of hydrogen & helium, methane atmosphere, great dark spot, strong winds, weather controlled from inside the planet

Copernicus

gets planets in the correct order an determined their rotation

Aristotle

theory was wrong but determined earth was round

Ptolemy

believed planets and sun orbit around earth