29.1 Flashcards
sphere
a round three dimensional object, the surface of which is the same distance from the center
ellipse
an elongated, closed curve with two foci
what are two factors that effect gravitational strength
the mass and the distance
which diameter of earth is longer
equator
what does the magnetic field protect the earth from
harmful radiation from the sun
the south magnetic pole is located in which hemisphere
the northern hemisphere
what degree is earths axis tilted at
11.7
do the magnetic poles reverse
yes
what is the large scale reversals called
magnetic reversals
how long do magnetic reversals occur
on averagre 200,000 years
when was the last magnetic reversal
780,000 years ago
what part of the magnetic field deflects harmful radiation from the sun
magnetosphere
what is the northern light called
the aurora borealis
what is the scientific name for the southern lights
the aurora australis
how are the auroras created
electrictally charged particles collide with atoms
