chapter 19&20 Flashcards
solar system
the sun and all of the planets AND other bodies that travel around it.
satellite
a natural or artificial body that revolves around a planet. Jupiter’s Ganymede & Saturn’s Titan are larger than the planet Mercury.
Phase
the change in the illuminated area of one celestial body as seen from another.
Eclipse
an event when the shadow of one celestial body falls on another. Solar eclipse: moon between the sun and the earth. Lunar eclipse: earth between the sun and the moon
terrestrial planet
one of the highly dense planets nearest to the sun: Mercury, Venus, Earth and Mars.
Astronomical Unit
the distance between the sun and the earth, 150M km.
hydrosphere
the portion of earth that is water
outer planets
Jupiter, saturn, uranus, neptune. All are gas giants
asteroid
a small rocky object that orbits the sun, usually in a band between the orbits of jupiter and mars, i.e. between the closest outer and farthest inner planets.
gas giant
a planet that has a deep, massive atmosphere, such as jupiter, saturn, uranus, or neptune.
Jupiter
the largest planet in the solar system; the giant red spot is a huge hurricane-like storm that has existed for hundreds of years.
Saturn Still Forming!!!!
Saturn radiates 3x the energy it receives from the Sun. Until it reaches equilibrium it will be considered to be forming.
The inner and outer planets are separated by an asteroid belt.
what’s its name?
Pluto’s strange
Pluto’s orbit is in a different plane from the rest of the platens in the solar system. as such, some scientists believe it was captured by the gravity of the sun sometime after the formation of the solar system.
Nebula
a large cloud of dust and gas in interstellar space; a region in space where stars are born or were stars explode at the end of their lives.
nebular model
a model for the formation of the solar system in which the sun and planets condense from a cloud (nebula) of gas and dust
accretion
accumulation of matter
comet
a small body of ice and rock, and cosmic dust loosely packed together that follows and elliptical orbit and that gives off has and dust in the form of a tail as it passes close to the sun.
meteorites
most meteorites are stony and have compositions like those of the inner planets and the moon.
moon
the moon may have formed when a mars sized object struck earth.
star
a large celestial body that is composed of gas and that emits light; the sun is a typical star.
light year
the distance light travels in a year, 9.5 Trillion km.
red giant
a large, reddish star lite in its life cycle
white dwarf
a small, hot, dim star that is the leftover center of an old star
supernova
gigantic explosion in which a missive star collapses and throws its outer layers into space.
stars
are spheres gas that produce energy by fusion. the composition of stars is measured using spectra
in most stars outward pressure balances
the inward pull of the star’s gravity
stars smaller than 1.4 solar masses become
red giants and then white dwarfs
massive stars larger than 1.4 solar masses become
supergiants and explode in supernovae to become neutron stars or black holes.
galaxy
a collection of stars, dust and gas bound together by gravity.
cluster
a group of stars or galaxies bound by gravity
interstellar matter
the gas and dust located between the stars in a galaxy
quasar
quasi-stellar radio sources; very luminous objects that produce energy at a high rate and that are thought to be the most distant objects in the universe.
universe
the sum of all space, matter and energy that exist, have existed, and will exist in the future.
red shift
an apparent shift toward longer wavelengths of light caused when a luminous object moves away from the observer
blue shift
an apparent shift toward shorter wavelength of light caused when a luminous object moves toward the observer
