6th Science Ch10

magnitude

brighness of a star

apparent magnitude

how bright a star appears

absolute magnitude

true brightness of a star

dwarfs

small-medium sized stars

giant stars

tens to hundreds of times larger & luminous

super giants

100’s times larger than the sun & 100’s times brighter than the sun

light year

distance light travels in a year

parallax

apparent movement or change in position of one star in relationships

variable stars

stars that repeatedly or regularly change in magnitude

pulsating variable star

one kind of variable star

eclipsing variable stars

doesn’t change its absolute, but does change apparent magnitude

nova

forms an existing star suddenly flares up & becomes brighter

nebula

cloud of interstellar gases & debris

supernova

death explosion of a star

neutron star

neutrons very tightly packedpu

pulsar

a ??? that spins rapidly on its axis

constellations

group of stars that make a pattern

circumpolar constulations

stars that revolve against the North Star

astronomy

scientific study of stars & heavenly objects

refracting telescope

bend or refract objects to make them bigger

reflecting telescope

produces a clearer magnified image

radio telescope

can detect objects that do not give off enough light to be detected by other telescopes

spectroscope

breaks down the light given off by a star into all its colors

redshift

??????

multiple star groups

small star groups have 3 or 4 stars

star cluster

large group of stars close enough to be held together by gravity

galaxy

large star system

local group

30 galaxys, milky way, form a cluster

asteroids

irregularly shaped pieces of rocks, metal, and dust

meteroid

a rocky object in space, smaller than an asteroid

meteror

meteoroid lit on fire

comets

an icy chuck of frozen gases, water, and dust that orbits around the sun