Planets & Universe
elliptical galaxy
huge galaxy that is round or oval in shape, has lots of old stars.
Mars
known as the red planet due to iron oxide in soil, named after the roman god of war; 4th planet from the sun.
galaxy
large group of stars, dust, and gas held together by gravity; can be elliptical, spiral, or irregular
blue stars
massive, hot stars that uses up its hydrogen quickly, expands, and turns into a giant or supergiant
asteroid
numerous celestial bodies composed of rock and metal that move around the sun (mainly between the orbits of Mars and Jupiter)
Pluto
reclassified as a dwarf planet Located in Kuiper belt
Mercury
smallest planet, closest to the Sun; has a thin atmosphere w/ temp. extremes, an iron core, & many craters & high cliffs
red giants
stars that reached old age, then increases in size and becomes very bright.
black dwarfs
stars that results when a white dwarf stops giving off energy and the final stage in the life of an average mass star ( like our sun).
solar system
sun, planets, and all the other objects that revolve around the sun
day
the amount of time it takes a planet to rotate one complete time on its axis.
apparent magnitude
the brightness of a star as seen from Earth
light minute
the distance light travels in one minute=18,000,000 km
Jupiter
the largest planet, the fifth planet from the sun; it has the Great Red spot and 69 known moons.
main sequence
the longest and most stable stage in the life cycle of a star
red giant
the next stage in the life cycle of our sun after being a yellow star.
neutron stars
the small, dense remains of a high-mass star after a supernova
light year
Distance light travels in a year
protostars
Early form of a star; This stage lies between the collapsing of dust and gas and the beginning of nuclear fusion
light minutes
Earth is 8.3 _______ from the sun.
black hole
Final stage in the life of a very massive star, where the core's mass collapses to a point that its gravity is so strong that not even light can escape.
Venus
This planet appears brighter than the others when seen from earth because it is the closest planet to earth.
Milky Way
This spiral shaped galaxy is only one out of billions of galaxies. Our solar system belongs to this galaxy.
sun
This star is at the center of our solar system
telescope
This tool is use to view distant objects by making them appear closer,such as planets and stars
light years
This unit is used to measure distance between stars because the distance between stars is so large (far apart).
rotation
a planet spinning on it's axis
revolution
a planet's yearlong elliptical orbit around the sun
planets
1) Large Round Objects 2) Orbits the Sun 3) clears most of its orbit of derbis 4)massive
Earth
3rd planet from sun; has an atmosphere that protects life & surface temp.'s that allow water to exist as a solid, liquid, & gas
Uranus
7th planet from Sun; is tipped on its side, a faint ring, and looks blue because of methane
Neptune
8th from the sun, furthest out, high methane content, has the great dark spot, low density, has 14 known moons
meteor
A STREAK OF LIGHT in the sky produced by the burning of a meteoroid in Earth's atmosphere
black hole
A final stage in the life of massive blue star, where the core's mass collapses to a point that its gravity is so strong that not even light can escape.
irregular galaxy
A galaxy that does not fit into any other category; one with an irregular shape
Great red spot
A giant storm, somewhat like a hurricane, on Jupiter that is more than twice as wide Earth.
meteorite
A meteoroid that passes through the atmosphere and hits Earth's surface.
moon
A natural satellite that revolves around a planet.
Kuiper Belt
A region of the solar system that is just beyond the orbit of Neptune and that contains small bodies made mostly of ice. Scientists think that comets come from here.
meteoroid
A relatively small (sand-grain to boulder size) piece of debris chipped off from an asteroid or comet that orbits in space.
gas giants
All of these planets have rings
main sequence
An area on the Hertzsprung-Russell diagram that runs from the upper left to the lower right and includes more than 90% of all stars.
satellite
An object that revolves around another object in space. A moon is a ________ to earth.
Neptune
Of all the major planets, this one has the longest year.
Venus
Out of the major planets, this one has the longest day.
gas giants
Outer Planets that are mainly composed of gas and that are very large
terrestrial planets
Planets that are small, dense, and have rocky surfaces, with a crust, mantle, and iron core), similar to earth
dwarf planets
Small round bodies that orbit the sun but have not cleared the area around their orbits of other orbiting bodies
closer
Stars that appear biggest and brightest to us are usually stars that are ____ to us.
Saturn
The 6th planet from the sun and the second largest in the solar system, know for its many rings, has 62 known moons
gravity
The _____ of the sun is what keeps the planets in orbit around the sun.
absolute magnitude
The actual brightness of a star
year
The amount of time it takes a planet to make a complete revolution around the sun.
day
The amount of time it takes earth to complete this motion.
stars
The appearance of these objects from earth is affected by their, size, temperature, distance 7 brightness.
astronomical unit
The average distance between Earth and the sun, about 150 million kilometers
Moon
The closest object in space to the earth.
Venus
The closest planet to earth.
Sun
The closest star to Earth and the center of our solar system.
supernova
The explosive death of a massive star
black dwarf
The last stage in the life cycle of a star like our sun.
black hole
The life of a very high mass star may end as a neutron star or a ___________________________.
Milky Way
The name of our galaxy, a spiral galaxy that contains about 400 billion stars
comet
This object is known as a dirty snowball because it is composed of ice and rock which breaks apart as it nears the sun.
main sequence
The red arrows point to _______________ ________________ stars._
asteroid belt
The region of the solar system between the orbits of Mars and Jupiter, where many asteroids are found.
month
The rotation and revolution time of the moon is approximately one _____.
comet
The tail of this object glows and gets longer as it gets close to the sun, in its highly elliptical orbit
gas giants
These four objects are known as _______
terrestrial planets
These four objects orbiting the sun are known as_______
blue stars
These stars have the highest temperature and highest luminosity (brightness)
meteor
These streaks of light are called shooting stars. They are also known as ______ showers.
Venus
This is the hottest planet in the solar system.
meteorite
What object most likely made this large crater?
blue stars
Which group of stars are the most massive with the highest luminosity (brightness)
red giants
Which stars are in their old age and have high magnitudes but low temperatures?
red dwarfs
Which stars have the lowest mass and lowest luminosity? (Brightness )
red dwarfs
Which stars have the lowest temperature and lowest luminosity?
blue stars
Which stars on the main sequence are hottest as well as brightest?
red dwarfs
Which stars on the main sequence are the dimmest as well as coolest?
yellow stars
Which stars on the main sequence have average temperature, brightness, and mass
nebula
a cloud of gas and dust in which new stars form
spiral galaxy
a galaxy with a bulge in the middle and arms that spiral outward in a pinwheel pattern, has lots of new stars
star
a huge ball of very hot gases in space
universe
everything that exists anywhere
