Question | Answer |
earth science | study of earth and of the universe around it |
geology | study of the orgin history processes and structure of the solid earth |
oceanogrphy | study of earths oceans |
meteorology | study of earths atmosphere |
astronomy | study of the universe beyond earth |
galaxy | large collection of stars |
astronomical unit | approximates the average distance between earth and sun |
electromagnetic spectrum | all of the wavelengths of electromagnetic radiation |
perihelion | point at which planet is closest to sun |
aphelion | point at which planet is farthes away from sun |
days in one year | 365 1/4 |
leap year | every 4 years the 1/4 day adds up and puts a extra day on febuary |
solstices | seasons of summer and winter begin on days |
equinox | the sasons fall and spring begin on days |
autumnal equinox | begins on september 22 or 23 of each year |
vernal equinox | begins on march 21or 22 of each year |
summer solstice | june 21-22 |
winter solstice | 21-22 |
solar system | consists of the sun the planets and all of the other bodies that revolve around the sun |
planets | the primary bodies that orbit the sun |
satellite | a body that orbits a larger body |
mare | dark areas on the moon |
craters | bowl shaped depressions on the moon |
rilles | long deep channels on the moon |
rays | streaks that extend outward from the impact site on the moon |
regolith | rock and dust on moons surface |
eclipse | occurs when one celestial body passes trhough the shadow of another |
umbra | sunlight is completely blocked |
penumbra | sunlight is only partially blocked |
solar eclipse | when the moon is directly between the sun and part of earth |
lunar eclipse | occurs when earth is positioned between the moon and the sun. |
star | ball of gases |
light year | distance traveled in one year |
apparent magnitude | brightness of a star as it appears to us on earth |
absolute manitude | the true brightness of a star |
matter | anything that takes up space and has mass |
element | substance that cannot be broken down into simpler |
atom | smallest unit of an element that has the chemical properties of that element |
isotope | atom that has the same number of protons as other atoms of the same element do but has a different number of neutrons |
average atomic mass | weighted average of the atomic masses of the naturally occuring isotopes of an element |
atomic number | number of protons in the nucleus of n atom |
mass number | sum of the number of protons and neutrons in an atom |
compound | substance that is made of two or more elements that are joined by chemical bonds between the atoms of those elements |
chemical bond | forces that hold together the atoms in molecules |
ion | particle such as an atom or molecule that carries a charge |
ionic bond | attractive force between oppositely charged ions that result from the transfer of electrons from one atom to another |
covalent bond | a bond that is formed by the attraction between atoms that share electrons |
mineral | a natural usually inorganic solid that has a characteristic chemical compsition an orderly internal structure and a characteristic set of physical properties |
luster | light that is reflected from a minerals surface |
cleavage | tendency of a mineral to split along specific planes of weakness to form smooth flat surfaces |
fracture | break unevenly into pieces that have curved or irregular surfaces |