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Earth data

MASSIVE EARTH’S ROTATION

VOL C ANO
LARGEST ONLAND
THE

THE LARGEST

SHIELD VOLCANO VOLCANO,

on Earth is under the Pacific Ocean, Mauna Loa, is one-sixtieth PLA
1,000 miles (1,600 km) east of Japan. of Tamu Massif’s size at DRIES
Tamu Massif covers 120,000 sq 2,000 sq miles
miles (10,800 km²)—the same area
as Thailand. (5,180 km³) in area.
Mauna Loa CES T

EARTH’S MAGNETIC FIELD

N
Earth’s magnetic field is created by the molten iron in Earth’s
outer core moving around. As the molten iron moves, so does the
magnetic field.
Earth’s magnetic poles move about 10 miles (16 km) a year.
Since the early 19th century, magnetic north has moved northward by
more than 600 miles (1,000 km). In recent years the speed has
increased to 24 miles (40 km) per year.

Every few hundred thousand years, the magnetic poles
reverse. When this happens, if you held a compass with the needle
pointing to “N,” it would actually be pointing south. These reversals
take hundreds or thousands of years—the last one occurred about
780,000 years ago.
S

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