Astronomy 3 Chapters 1-4

Rotation- the spinning of Earth on its axis
Revolution-the movement of one object around another
the days when the sun is farthest north of south of the equator
the days when neither hemisphere is tilted toward or away from the sun
a push or pull
Mass vs Weight
Mass : amount of matter in an object
Weight: the force of gravity on an object
Inertia the tendency of an object to resist a change in motion
Scientific method
approach to investigation combiningthinking and doing thatis theory and experiment also known as scientific method. the process combining theoretical reasoning experimental testing.
Umbra When the moon is in the Earth's ____, you see a total lunar eclipse.
penumbra shadow when a full lunar eclipse occurs
geocentric describes the concept of an Earth-centered universe
heliocentric describes the view that the sun is at the center of the solar system
Astronomical unit (AU)
astronomical unit (AU) average distance from he Earth to the sun; 1.5 × 10⁸, or million kilometers
ellipse an oval
perihelion, aphelion
perihelion the point in the orbit of a planet where it is closest to the sunaphelion the place in the orbit of a planet where the planet is farthest from the sun
precession a slow motion of Earth's axis that traces out a cone over a period of 26,000 years
Perigge, apogee
perigee the point at which the moon is closest to the Earth
apogee the point where the moon is farthest from Earth
solar eclipse an eclipse of the sun; a solar eclipse occurs when the moon moves in a line directly between Earth and the sun, casting a shadow on earth
lunar eclipse an eclipse of the moon; occurs when the moon passes through Earth's shadow
Kelpers Laws
Kepler law #1 all planets orbit sun in ellipse
Kepler law #2 when a planet is closer to the sun in its orbit, it moves faster
Kepler law #3 T²=D³ (the time of a planets orbital period ² is proportional to the average distance³
Galileo Onservations
Galileo Galilei greatest scientist of Italian Renaissance
Galileo Galilei discovered 4 large satellites of Jupiter
Galileo Galilei discovered planets Earth-like
Galileo Galilei discovered Venus had phases like moon
Galileo Galilei discovered Sun had dark regions (sunspots)
Newstons Laws
Sir Isaac Newton formulated law of universal gravitation
Sir Isaac Newton every body in universe attracts to other bodies with a force that is directly proportional to their mass and inversely proportional to the ² of the distance between centers of mass
Law of universal gravitation
Synodic Month, Day
synodic month new moon --> new moon is called
sidereal day, month, year
sidereal month earth, moon, and star are all aligned
Electron Negatively charged particle found OUTSIDE the nucleus.
Proton Positively charged particle found INSIDE the nucleus.
Isotope Any of two or more forms of the same element whose atoms all have the same number of protons but different numbers of neutrons.
Refraction The bending of light when it passes from one transparent medium to another. Different colors of light ____ by different amounts.
Spectroscopy The study of spectra
Velocity, Speed
Velocity The speed (and direction) of propagation of a wave disturbance through a medium
Wavelength Distance between two identical points on successive waves. Different ____ refer to different colors.