Earth, Atmosphere and Outer Planets
Earth is the fourth planet from the Sun and only cosmic object known to host and support human life. Only within the last few million years has Earth had an atmosphere and oceans, both of which are vital for sustaining life. At the present time there are about four billion human beings living on Earth. Earth’s crust is composed of several plates which have been in existence for millions of years. In fact, the presence of such a long history of life on Earth can be attributed to the fact that Earth was able to gather enough solar radiation to keep its molten interior molten while in the solar system it remained molten from the beginning until the end of the solar system.
The earth orbit is tilted so that it takes around 24 hours for the earth to rotate once around its axis, once every almost half a century. The tilt of the earth’s axis allows the planet to receive as much as three times more solar radiation than it does from the sun. This radiation heats the planet and makes it habitable, which is what led to the development of life on Earth. Astronomy has shown that there are several indications that there were bacteria on Earth prior to the establishment of the earth’s complex solar system around 4.5 billion years ago.
Another way to understand the relationship between Earth and the sun is to consider the process through which a rocky planet like Earth obtains its tilt. Basically, the tilt of an object depends upon the mass that it has and the speed with which it moves relative to its axis of rotation. The tilt of the earth’s axis of rotation is very similar to that of the tilt of the orbit of the earth relative to the sun. The tilted angle of the earth’s orbit to the solar system is called an ephemeris, which can be used to determine the mean solar system distance. From this information scientists and astrologers have determined that the earth is approximately tilted at roughly forty five degrees to the plane of the solar system, or about two hundredths of a degree.
One of the ways in which the earth obtains its tilt is through the impact of objects on its surface. When two large objects collide near each other the momentum of both objects tends to shift due to their mutual attraction and gravity. This shift in momentum leads to the rotation of the planet, which causes it to tilt slightly. Scientists have determined that there are some instances when the tilt of the planet’s axis of rotation is as much as forty five degrees. To put these numbers in perspective, the tilt of the inner planets Jupiter, Saturn, Uranus, and Neptune are less than ten degrees, while the tilt of the earth is nearly forty degrees. So the planet’s tilt could account for the existence of life on Earth, even though it is difficult to think of any organic materials on the surface of the planet.
The tilt of the planet Saturn is nearly forty degrees, which would place it into a similar solar-system formation that our planet belongs to. This means that the planet, or more specifically, its innermost planet Triton, must be made up primarily of water. Water can condense into rock or ooze at very low temperatures, which would make Triton unlike any other planet in our solar system. If Triton was not made primarily out of water, then it could only have a very thick atmosphere. The rocky outer layer of Triton would be very different from the mineral composition of the inner most planet in our solar system, Jupiter. It would also be very strange for the tilt of Saturn to be nearly forty degrees, if not more.
The earth’s tilt, however, is also caused by the effects of other planets on it. For example, the earth’s tilt to the solar system is affected by Proton concentration. Proton concentration is influenced by the abundance of heavy element, such as iron, in a planet’s atmosphere. Since Triton is very heavy, it requires an extremely rich, ionized atmosphere to produce the rock that is characteristic of Triton. If other worlds in the solar system have significantly less water content, than Triton, then Triton’s atmosphere will be very similar – and will therefore also be very different.