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Origin of the Earth and Solar System

Directly from the New Physical Setting New York State Standards:

Key Idea 1: The Earth and celestial phenomena can be described by principles of relative motion and perspective.

• People have observed the stars for thousands of years, using them to find direction, note the passage of time, and to express their values and traditions. As our technology has progressed, so has understanding of celestial objects and events.
• Theories of the universe have developed over many centuries. Although to a casual observer celestial bodies appear to orbit a stationary Earth, scientific discoveries led us to the understanding that Earth is one planet that orbits the Sun, a typical star in a vast and ancient universe. We now infer an origin and an age and evolution of the universe, as we speculate about its future.
• As we look at Earth, we find clues to its origin and how it has changed through nearly five billion years, as well as the evolution of life on Earth.

Note: Our sun is a second generation star. There was an earlier star/sun that exploded into a supernova, creating heavier elements.

Evidence:

• Iron is the heaviest element that can be created in a star through nuclear fusion.
• Gold, silver, titanium, uranium (all heavier elements than iron in the sun and on Earth) had to be created by neutron capture during a violent explosion marking the end of a star's life.
• The stuff that makes us up, first formed with a Supernova! 
• "almost all of the elements in the Universe that are heavier than hydrogen and helium are created either in the centers of stars during their lifetimes or in the supernova explosions that mark the demise of larger stars. Supernovae then explode this newly synthesized material into space. From this material a new, enriched generation of stars will form, and the cycle begins again. This is how we think that the heavy elements in the Sun came to be. Since the planets in the solar system formed from leftover material in a disk around the proto-Sun, all of the heavy elements in the Earth (including those in humans!) must have come from the same source.
  This means that in the most literal sense, we are stardust!"  

We are all made of star stuff!

Where are stars being born now? __________________

The constellation Orion: right beneath the three stars in the belt of Orion, where his knife is held is the Orion Nebula.  This Nebula shows us newly forming stars.  I suppose you could call it where stars are born.

Nebulas: interstellar cloud of dust and gasses.
Gravity pulls this material together until it is so compact that nuclear fusion (the H-bomb) starts a constant reaction "sparking" the early protostar's core.

The Proto-planet Hypothesis (Nebular Hypothesis):

• About 4.6 billion years ago, after a long period of gravitational attraction, a nebula collapsed to form the sun and its solar system. 

1. The solar system formed from an immense rotating cloud of gas and dust called the solar nebula.
2. The sun's nuclear reaction began at the dense center of the nebula.
3. The planets formed by accumulating material within the swirling currents of the cloud.
4. Planets near the sun evolved as relatively small spheres of rocky material.
5. In the outer portions of the solar nebula, debris and gases accumulated to form massive gaseous planets.

Evidence for the Proto-planet Hypothesis:

1. Most objects in the solar system move in regular and predictable motions.
2. All planets orbit sun in the same direction (Counterclockwise).
3. Rotation of Sun and most planets is also counterclockwise.
4. Orbits are basically co-planar (flat).
5. Orbits nearly circular (slightly elliptical).
6. The sun spins almost along planets orbital plane.
7. Most planets rotate in the same direction as the sun.
8. The gaseous planets are farther away from the sun.

Be careful of deceptive teaching!

• Some people claim that the solar system could not have formed from the collapse of a revolving nebula because three planets and several moons revolve backwards.

Explanation (talkorigins.org):

• The "backwards" planets and moons are in no way contrary to the nebular hypothesis. Part of the hypothesis is that the nebula of gas and dust would accrete into planetessimals. Catastrophic collisions between these would be part of planet building. Such collisions and other natural processes can account for the retrograde planets and moons. The only moons that orbit retrograde are small asteroid-sized distant satellites of giant planets such as Jupiter and Saturn, plus Triton (Neptune's large moon) and Charon (Pluto's satellite). The small retrograde satellites of Jupiter and Saturn were probably asteroids captured by the giant planets long after formation of the solar system. It is actually easier to be captured into a retrograde orbit. The Neptune system also contains one moon, Nereid, with a highly eccentric orbit. It appears that some sort of violent capture event may have taken place. The Pluto-Charon system is orbiting approximately "on its side," technically retrograde, with tidally locked rotation. As these are small bodies in the outer solar system, and binaries are likely to have been formed through collisions or gravitational capture, this does not violate the nebular hypothesis.
• Uranus is rotating more or less perpendicular to the plane of the ecliptic. This may be the result of an off-center collision between two protoplanets during formation. Venus is rotating retrograde but extremely slowly, with its axis almost exactly perpendicular to the plane of its orbit. The rotation of this planet may well have started out prograde, but solar and planetary tides acting on its dense atmosphere have been shown to be a likely cause of the present state of affairs. It is probably not a coincidence that at every inferior conjunction, Venus turns the same side toward Earth, as Earth is the planet that contributes most to tidal forces on Venus.
• Orbital motions account for 99.9% of the angular momentum of the solar system. A real evidential problem would be presented if some of the planets orbited the sun in the opposite direction to others, or in very different planes. However, all the planets orbit in the same direction, confirming the nebular hypothesis, and nearly in the same plane. A further confirmation comes from the composition of the giant planets, which are similar to the sun's composition of hydrogen and helium. Giant planets could hold on to all of their light elements, but small planets like Earth and Mars could not.

Creation myths: Top 10 Creation Myths

	Solar Power?
	The Horse Head

Movie Clips
Click on the links

From Dust to Star Dust!
Stages of a star's life
The Orion Nebula!
Solar System Formation

SOHO Observatory

Fly to a sun spot! 25 mb
Our Dynamic Sun 27 mb
Crazy Solar Photos 12 mb
Mass Ejections! 9 mb
Solar Flairs! 16.5 mb
Sun Spot! 7.5 mb|
A mass ejection 1.6 mb
Solar Weather? 15 mb