Catastrophic Events in the Solar System There are records in the surface and interior of the planets...

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Catastrophic Events in the

Solar System

Catastrophic Events in the

Solar SystemThere are records in the surface and interior of the planets and their satellites that indicate the

occurrence of VERY LARGE impacts that have drastically altered the character of the solar

system. These events are unpredictable and not adequately accounted for in the standard model

of planet formation (Solar Nebula Theory).

There are records in the surface and interior of the planets and their satellites that indicate the

occurrence of VERY LARGE impacts that have drastically altered the character of the solar

system. These events are unpredictable and not adequately accounted for in the standard model

of planet formation (Solar Nebula Theory).

Catastrophic Events: EarthCatastrophic Events: Earth

• The formation of the Moon is now accepted to be due to a grazing collision of a Mars-sized planet with the early Earth after the Earth’s core had formed (Step 6 in the standard model). The collision destroyed the impacting planet and the ejecta re-accreted to form the Moon.

• The moon has three important physical properties that any formation scenario must predict.

• The formation of the Moon is now accepted to be due to a grazing collision of a Mars-sized planet with the early Earth after the Earth’s core had formed (Step 6 in the standard model). The collision destroyed the impacting planet and the ejecta re-accreted to form the Moon.

• The moon has three important physical properties that any formation scenario must predict.

First, the density of

the Moon is 3.3 gm/cm3, substantially less than the Earth’s bulk density, but similar to

the density of the

Earth’s crust and upper

mantle.

Second, Moon rocks are

depleted in iron. There is much

less iron in Moon rocks than

in the rocks found on the

Earth’s surface.

Third, Moon rocks are devoid of bound water. Even meteorites have up to 5% water bound into the mineral

structures. The Moon has no water in its rocks.

Earth after its iron core has formed

A Mars-sized planet on a grazing

collision course with the Earth.

The Hypothesized Collision that Formed the Moon

Whamo!

Crust and upper mantle

material is ejected into Earth orbit

The Hypothesized Collision that Formed the Moon

The Hypothesized Collision that Formed the MoonThe iron core of

the impacting body does not

escape but falls back into the Earth to join the Earth’s

core.

The Hypothesized Collision that Formed the MoonThe lighter

material from the Earth’s crust and mantle has been heated so

much during the impact that the

bound water has vaporized and

escaped.

The Hypothesized Collision that Formed the MoonEarth’s new Moon has formed from the iron poor and dried out crust and upper mantle

rocks of the Earth and its impactor.

Interior

of the

Moon

Notice the relatively small

iron core

Venus

Earth Mars

Mercury

Moon

The Moon’s relatively small iron core bulk geology are consistent with a birth by a violent collision

The Moon preserves a record of

catastrophic events itself. This multi-ring impact basin on the

Moon is called Mare

Oriental.

The impact portrayed in this artist’s impression is far smaller than the impact that created our Moon.

The currently accepted scenario for the Moon’s formation would not have been possible with the

aggressive exploration of the Moon and other planets.

Ganymede is a natural satellite the size of Mercury. Its surface preserves the evidence of a giant impact

that formed this multi-ring basin called Vahalla.

Recent impact craters reveal the clean ice that makes up most of this moons mass.

This small natural satellite called

Miranda has surprising

surface features for an object its

size (236 km radius).

Miranda has both ancient

cratered terrain

indicating great age

and an unusual

“chevron”-terrain that indicates

recent resurfacing.

This Voyager image of Triton

hints at the satellites violent past. Notice the

two distinct terrains and the lack of

impact craters. The capture event

created enough energy to

completely melt the satellite erasing previous ancient

craters and creating a new terrain.

Cantaloupe-terrain

Few Craters and Ice Volcanoes-terrain

This type of terrain is unique in the solar system. The lack of craters implies a relatively young age of this

surface.