HOW DID THE PLANETS FORM?

HOW DID THE PLANETS FORM?

By Edward Hujsak

( What follows seems obvious, but there are theories and theories, all supported by their own sets of conjectures.)

A common theory about the moon, generally accepted, is that it was scarfed out of Earth when a huge asteroid passed close by. Another theory is that it was somehow handed off from Venus. But evidence to the contrary is in plain sight. Mars, Jupiter, Saturn, Uranus, Neptune.....all have multiple moons....as many as sixty-seven in orbits around Jupiter.

What is uncontested is that the planets' beginnings were in the form of gas blobs. Uncontested because the outer planets, Jupiter, Saturn, Uranus and Neptune still exist in that state. It is likely, from observation of other planets, that surrounding the gas blobs were lots of rocks which were gradually drawn into the gaseous spheres through loss of momentum caused by collisions, and gravity, ending up as solid planets with a surrounding atmosphere.Some of the rocks were too big to be drawn in. Our moon is one of them.

How the planets evolved after that is apparently dependent on the strength of their gravitational fields. Mercury, for example was too small to hold on to its atmosphere. Closest to the sun, it was simply blown away by solar pressure. Venus, next closest to the sun, with a gravity like Earth's, has an atmosphere rich in carbon dioxide, a greenhouse gas, and its nearness to the sun resulted in runaway global warming.... a window into a possible fate for Earth if carbon dioxide concentration reaches a tipping point. We do not have any idea what that tipping point is.

Earth, occupying an orbit averaging about ninety-four million miles from the sun, had a strong carbon dioxide component component. When it cooled, plant life became possible, out of which the atmosphere acquired a strong oxygen component. That, in turn, made animal life possible.

Mars, unfortunately, with a gravity only thirty-eight percent that of Earth, suffered the same fate as Mercury. Its atmosphere was blown away. Some life may have formed there, and possibly still exists in underground caverns but so far no evidence has been uncovered. A visitor to Mars might survive in a deep cavern. But had better like to eat mushrooms, as they would likely thrive in a damp. warm enclosure.

The outer gas planets will probably never reach a state like Earth- a large body of merged rock with a surrounding thin atmosphere, though they have all accumulated some rocks, as shown by evidence of solid cores. Also, the gas blobs are just too big. There simply aren't enough rocks. Saturn, maybe, if collisions cause enough loss of momentum to cause the ring matter to be drawn in. But Saturn is pretty far out. Solar pressure, the only known significant disturbing influence is small at Saturn's distance from the sun.

In any case, none of the giant gas planets could support life as we know it.

Planet forming – a big show- and right before our eyes! Slow, though. A lifetime is too short to see any action.