posted on Sep, 20 2007 @ 10:04 PM
I don't know if this has been posted or not, but here you go if in case you missed it.
1. Gravity is not the same over the surface of the Earth
It turns out that in some places you will feel slightly heavier than others. A low spot can be seen just off the coast of India, while a relative high
occurs in the South Pacific Ocean. The cause of these irregularities is unknown since present surface features do not appear dominant. NASA's GRACE
twin satellites, launched in March 2002, are making detailed measurements of Earth's gravity field which will lead to discoveries about gravity and
Earth's natural systems.  
2. Atmosphere 'escapes'
Due to thermal energy, some of the molecules at the outer edge of the Earth's atmosphere have their velocity increased to the point where they can
escape from the planet's gravity. This results in a slow but steady leakage of the atmosphere into space. Because unfixed hydrogen has a low
molecular weight, it can achieve escape velocity more readily and it leaks into outer space at a greater rate. For this reason, the Earth's
current environment is oxidizing, rather than reducing, with consequences for the chemical nature of life which developed on the planet. The
oxygen-rich atmosphere also preserves much of the surviving hydrogen by locking it up in water molecules.
3. The Earth is slowing down
As a result of variation in gravitational forces due to the moon, the sun and other planets in the solar system, displacements of matter in different
in different parts of the planets and other excitation mechanisms, the rotational speed of the Earth about it's axis varies in time. Recently, days
have been getting shorter by hundredths of a second, which implies that the angular velocity of the Earth has been increasing. The factors causing
this increasing in the Earth's rotational velocity have not been determined. The rotation data shows oscillations over several different timescales.
The one with the largest variation is seasonal: Earth slows down in January and February.   
4. Van Allen radiation belt
The Van Allen Radiation Belt is a torus of energetic charged particles (plasma) around Earth, held in place by Earth's magnetic field. Apollo
astronauts who traveled to the moon spent very little time in the belts but probably have a slightly higher risk of cancer during their. NASA said
that they deliberately timed Apollo launches, and used lunar transfer orbits that only skirted the edge of the belt over the equator to minimize the
radiation. Besides, there have been nuclear tests in space that have caused artificial radiation belts. Starfish Prime, a high altitude nuclear test
created an artificial radiation belt that damaged or destroyed as many as one third of the satellites in low earth orbit at the time.  
5. Moon is moving away from Earth
The reasons why have to do with tides and conservation of energy and angular momentum. Measurements have been collected now for over 25 years, and it
is clear that the Moon's orbit is slowly growing larger and that the Moon is moving away from the Earth. The net result is that the Moon is receding
from the Earth at about 4 centimeters a year. However, astronomers have predicted that when the Sun enters the red giant phase in around 5 billion
years - during the red giant phase of the Sun - both Earth and Moon will be affected by the Sun's extended atmosphere and will aproach again. Then
the Moon will swing ever closer to Earth until it reaches a point 11,470 miles (18,470 kilometers) above our planet, a point termed the Roche limit.
The result: Moon will be torn to pieces and will be scattered to form a spectacular 23,000-mile-diameter (37,000-kilometer) Saturn-like ring of debris
above Earth's equator.