Exam 1 Earth Science - The University of Akron

What is the contracting earth theory?

Late 1800s, believed mountain ranges formed due to Earth GROWING SMALLER as it COOLED... "primitive" science, sounds good, lacks sufficient evidence.

What is the continental drift theory?

Early 1900s, Alfred Wegner, earth's continents were in motion across a global ocean floor. Doesn't explain ALL mountains.

What is the expanding earth theory?

1960s, earth growing larger with time. They thought that this was the reason for the continental drift. They believed that the force of gravity was growing weaker, allowing the earth to expand (bad science... violates the laws of physics).

What are the 4 terrestrial planets?

Mercury, Venus, Earth, Mars

What are terrestrial planets made of?

rock and metal

Mercury

Smallest and closest planet to the sun

Geology: geologically dead, but was volcanically active in the past. It is the smallest planet and lost most of its internal heat long ago. Today, it is covered with craters.

Water: No liquid surface water

Atmosphere: Extremely thin and insignificant atmosphere

Venus

90% co2 and hotter than mercury even though further away than Mercury

Geology: Volcanically active and is probably seismically active as well. Appears to lack significant plate tectonics.

Water: None (its lack of tectonics may be partly due to its lack of surface water).

Atmosphere: It has an extremely dense atmosphere dominated by carbon dioxide and extremely corrosive acid rain.

*no distinct seasons and little variety in its weather. It also is tilted upside down, so it rotates "backwards" and slowly.

Moon

Geology: The moon was volcanically active in the distant past, but is almost completely dead now. Only minor releases of gas and some small "moonquakes" still occur.

Water: No liquid surface water, but ice exists in some polar craters

Atmosphere: No significant atmosphere

*not much smaller than Mercury and might be considered a planet, if it were by itself and not orbiting the earth.

Mars

Geology: Mars is almost completely dead, but some volcanic activity may still occur. Mars has the solar system's largest volcanoes somewhere similar in the types to those in Hawaii.

-> the insight lander recently detected marsquakes and will use them to examine the planet's interior structure.

Water: No permanent liquid surface water today, but did in the past. It appears to have had rivers and a shallow oceans. Underground water still exists and may briefly flow to the surface.

-> mars has polar ice caps

Atmosphere: It has a very thin, carbon dioxide dominated atmosphere and dust storms.

-> co2 atmosphere

What are the Jovian planets?

Jupiter, Saturn, Uranus, Neptune

What are Jovian planets made of?

hydrogen, helium, and hydrogen compounds (gases)