Chapter 9 Moon Flashcards
annular eclipse
exterior of the sun can be seen around the object due to distance
ascending node
moon moving northward across the ecliptic
Bailey’s beads
just before totality, the sun still be seen through valleys on the rim of the moon.
binary accretion theory
earth and moon formed from same material cloud. doesnt explain moons lack of iron
corona
outer region of the suns atmosphere that can only been seen during a total eclipse
descending node
moon moving southward across the ecliptic
diamond ring
final glimpse of the sun, just before totality, appears especially bright because the sun is otherwise eclipsed
eclipse season
when the line of nodes points directly enough at the sun for eclipses to occur during intervals of time, usually a month
eclipse track
the path of the moon’s umbra shadow across the earth
eclipse year
interval separating successive times when the same node of the moons orbit is aligned with the sun.
fission theory
moon broke away from earth due to rapid rotation. doesnt explain the moons orbits plane
giant impact theory
moon formed when debris from another object struck the moon.
line of nodes
the imaginary line that connects the two nodes of the moons orbit
maria
dark regions of the moon
mascon
concentrations of mass caused by the intrusion of dense mantle material beneath the maria
penumbra
outer part of the shadow, only part of the sun’s disk is blocked
regolith
layer of surface debris from craters
rilles
winding or straight lunar features caused by volcanic activity
saros
length of time between one member of the series of eclipses to the next.
sinuous rille
rilles that occur in marias and resemble dry river beds
synchronous rotation
an object that rotates and orbits in the same length of time
terrae
light regions of the moon
umbra
inner part of the shadow cast from an object. no sunlight penetration.
Capture theroy
moon formed elsewhere and was caught by earth
