Stars, Galaxies, Constellations
What is related to a star's surface tempurature?
Giants or Supergiants
What are the biggest stars?
What is a medium size star?
White Dwarf Stars
What is a small- medium star?
What is the smallest star?
can use a spectrograph to identify the chemical elements in a star
depends on a star's size, composition, temperature and distance from Earth.
brightness the star would have if it were a standard distance from Earth ( actual brightness)
star's brightness as seen from the Earth.
the apparent change in position of an object when you look at it from different places used to measure distances to nearby stars
Hertzsprung- Russell Diagram
a graph that plots absolute magnitude versus temperature of a star.
large cloud of gas and dust; gravity pulls gas and dust together, temp. increases
beginning stage, nuclear fusion begins
hydrogen changes to helium, may last for billions of years depending on mass.
star's outer surface cools, expands and becomes red
final stage depends on mass
red giant collapses and becomes a white dwarf.
forms planetary nebula when a white dwarf
explodes- supernova, then may become a very dence neutron star or an extremely dense black hole.
smaller and denser than white dwarfs
spinning neutron star- gives off radio waves
an object with gravity so strong that nothing escapees.
What is 15th brightest star in the sky?
1000 light years away
How far is Antares from Earth?
a group of stars that form a pattern.
How many constellations are accepted worldwide?
for navigation and calendar
What were constellations used for?
5 constellations seen throughout the year, rotate around Polaris
(Great Bear) contains the Big Dipper; stars at end of its bowl points ot Polaris
(Little Bear) little dipper; polaris is at end of its handle
band of 12 constellations moving across the sky throughout the year.
Orion, Canis Major, Taurus, Gemini
double stars, contain 2 stars
loose, disorganized in appearance. contain < 1000 or equal too.
large groupings of older stars; may contain > or equal too 1 million stars.
huge systems of billions of stars, star clusters, dust, and gas held together by gravity
disk-shaped with bulge in the center and spiral arms
Milky Way Galaxy
our sun is on one arm
slightly flattened spheres with bright centers, very little gas and dust, contain only old stars.
no regular shape, many stars and great clouds of gas and dust
Large Magellanic and Small Magellanic Cloud
Name 2 Irregular Galaxies
active young galaxies with giant black holes at their centers.