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This ones about gravity, admittedly a little random, but within the topic of astrology it explains a few things.

First the general idea of gravity as brought to us by Sir Isaac Newton, an english scientist (1642-1727). His idea was that gravity acts as a force between two objects, one based on mass and seperation. Basically it boiled down to; the greater the object, the greater the force, however the greater the distance, the less force.

Where Newton's idea is fine and dandy for the common gravity, Albert Einstein's theory of gravity explains why stars near the sun in an eclipse seem out of position, why gravitational lensing is found when we observe deep space, why, as earth turns, warped space and time are dragged with it, and why black holes exist. Einstein's theory works because he thought of gravity not as a force, but as the bending of time and space due to the presence of a object with a large mass, like a star.

Despite not being as correct as Einstein, Newton did get alot right, Einstein just carried on his idea and ended up a little ways down the road with some more information. Newton did manage to explain some things though, like; why the moon orbits the earth and why the earth orbits the sun and why the sun orbits the milky way, etc, why the planets are round, and why combinations of gas and dust forms a new star.

The point of this is that all of space is constantly moving, including us. The earth rotates on its axis, taking a day for one complete turn, as it orbits the sun, taking a year to complete, as it travels with the sun in orbit around the milky way, taking 226 million years to complete once (otherwise known as a galatic year), as it moves with the milky way around the center of the local group of galaxies, as it moves through the universe with the local group as part of the hubble flow.
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Why do stars near the sun in an eclipse seem out of position?
Because, as discovered by Arthur Stanley Eddington, astrophysicist, who tested Einstein's theory that space was distorted by gravity, hence light that would pass through it would not travel in a straight line, as it would follow the curved patten by the distorted space, so long as the mass of the object was great enough; hence Eddington tested it on the objects of the greatest mass he knew of. He tested this by observing the stars during a eclipse of the sun, revealing distant ones close to the sun, if Einstein was right, the gravity of the sun would shift the the stars to different positions, compared to when they are visible after the sun has shifted. This was viewed in the 1919 eclipse, with totality at around 6 minutes, at the sun in front of Hyades, a cluster of particularly bright stars.

Why gravitational lensing is found when we observe deep space?
Well, gravitational lensing is the distribution of matter between a distant source and an observer, it is capable of bending the light from the source as it travels towards the observer. They are created as a consequence of gravity and are basically a warped, closer image of an object that is farer away, hence it is also known as 'mother nature's telescope'.

Why as the earth turns warped space and time are dragged with it?
It works because as a ball in goo, when spinning, will cover itself in the goo, before coninuing and pulling more goo with it, earth works in the same way, although with space-time being pulled instead of goo. This occurs due to the gravity of earth, and the fact that the curvature of spacetime being connected to the energy and momentum of whichever object of matter is present. 

Why black holes exist?
Most black holes form from the remains of a star that dies in a supernova explosion, so long as the star is large enough, as the smaller ones become dense neutron stars. (that are a kind that cannot trap light due to their small stature.) A black hole occurs when the total mass of a star is large enough, around three times of the mass of the sun, it will, theorectically, collapse under the gravity. When the star collapses, it nears the 'surface' of the event horizon, and the time dimension of the star stands still, hence the star cannot collapse any more, where it becomes a frozen collapsing mass. Its a natural phenomenia.

Why the moon orbits the earth, etc?
It's mainly due to gravity, for example if you swing a weight in a circle around you, the weight moves because you move, the earth is you, the moon is the weight and gravity is the string.

Why the planets are round?
Because their gravitational field in the core of the planet, pulls everything towards it, and the only way to get everything towards the center as much as possible is to cut corners, hence a sphere.

Why combinations of gas and dust can form a new star?
A star is formed inside a dense interstellar cloud, made from gas and dust, at around 10 to 20K (just above absolute zero.) which allows the gases to bind together in high densities, once the denser areas of the coloud core collapse under their own gravity a star actually begins to form. The core has around 10 4 solar masses in the cloud, although the cores are denser than the outer cloud hence why the collapse at first. The cloud will then seperate into clups of around 0.1 parsecs in size and 10 - 20 solar masses in mass. The clumps then become protostars, with their own gravity, and loose gas, remaining from the original cloud, enters the center; which in turn release kinetic energy to form heat, building up the temperature and pressure until it becomes an IR (infared) source.