Affects of a Blackhole on Earth.

[BlkbrryTheGreat]

What would we precieve on Earth if a Blackhole appeared and slowly moved, over a period of a year, to the the point where we would just lose consciosness from the sheer gravity (or whatever, all that important is that we lose consciousness or are dead by that point). The "appears" is meant to b e were we actually "see" the Blackhole or are affected in some way by its gravity, meaning that we're close enough to it that i ts gravity starts to signifigantly affect us.

[Exonerate]

All we'd "see" would probably be a black void... There would be radiation eminating from it though.

[Hotfoot]

What would we precieve on Earth if a Blackhole appeared and slowly moved, over a period of a year, to the the point where we would just lose consciosness from the sheer gravity (or whatever, all that important is that we lose consciousness or are dead by that point). The "appears" is meant to b e were we actually "see" the Blackhole or are affected in some way by its gravity, meaning that we're close enough to it that i ts gravity starts to signifigantly affect us.

The whole solar system would likely be thrown into total chaos as the black hole approached. Black holes have a mass greater than the sun at the very least, IIRC, and that's if they're brand new. Something that's moving around is probably a bit older. As it approaches Sol, planetary orbits would be changed as every celestial body in the system is subjected to the gravity well of the black hole. Earth would ripped out of orbit with Sol, and Luna would be ripped out of orbit with Earth, playing hell with the tides if not outright crashing into the Earth. Earth would grow cold, drifting farther and farther away from Sol. Eventually, the atmosphere would be ripped from the planet by the black hole's gravity well. Depending on the positions of the planets at the time, Earth could very well collide with Mercury, Mars, or Venus on the way in. We should all be long dead by the time, and any survivors won't last long anyway, as the planet's water soon follows the atmosphere into the massively dense corpse of a star. Finally, once Earth passes the event horizon, the only things possibly left alive are some single-celled organism who will be dead quite soon, given that they are holding one-way tickets to the universe's ultimate trash compactor. The black hole, having eaten the planets, either proceeds to devour Sol, or drags our hapless star along with it as a snack for the road.

I'd imagine it happening something like that, anyway.

[Durandal]

What would we precieve on Earth if a Blackhole appeared and slowly moved, over a period of a year, to the the point where we would just lose consciosness from the sheer gravity (or whatever, all that important is that we lose consciousness or are dead by that point). The "appears" is meant to b e were we actually "see" the Blackhole or are affected in some way by its gravity, meaning that we're close enough to it that i ts gravity starts to signifigantly affect us.

It depends on the trajectory of the black hole. More than likely it would be attracted to our sun, and the two would begin orbiting each other.

Of course, everyone on Earth would die because a significant portion of the light from the sun would not reach Earth, and the orbits of every planet would be drastically altered, resulting in global catastrophes.

[GrandMasterTerwynn]

What would we precieve on Earth if a Blackhole appeared and slowly moved, over a period of a year, to the the point where we would just lose consciosness from the sheer gravity (or whatever, all that important is that we lose consciousness or are dead by that point). The "appears" is meant to b e were we actually "see" the Blackhole or are affected in some way by its gravity, meaning that we're close enough to it that i ts gravity starts to signifigantly affect us.

If a 1.4 solar-mass black hole (Really the minimum you can have without having a leftover from the formation of the universe,) approached our solar system, then the outcome depends on the black hole's trajectory.

If it passes through the Oort cloud, then it's passage will shake loose a large number of comets. A few millenia later, you get mass extinction on Earth as one of those comets comes a-calling.

If it passes through the solar system proper, it's effect will be like any other stellar-sized mass passing through the solar system. At the very least, the orbits of the planets, including Earth's, could be severely altered. And severely altered encompasses both orbits that become parabolic, or even hyperparabolic (where a planet is just ejected from the solar system.)

[Zoink]

What would we precieve on Earth if a Blackhole appeared and slowly moved, over a period of a year, to the the point where we would just lose consciosness from the sheer gravity (or whatever, all that important is that we lose consciousness or are dead by that point). The "appears" is meant to b e were we actually "see" the Blackhole or are affected in some way by its gravity, meaning that we're close enough to it that i ts gravity starts to signifigantly affect us.

You would never actually see the black hole. You'd probably see a visual distortion, composed of light that's been warped around the black hole. You'd also see a disk around it, composed orbiting material that is slowly falling inward.

With a very small blackhole, you (and earth) would be be torn apart from tidal forces (the difference in gravity between your feet and head would be so great that you'd be ripped apart) before you reach the event horizon.

With a very large black hole, the tidal forces are smaller, and you could fall into the black hole in one piece.

Past the event horizon, time and space become warped and its a little hard to describe, this guy made a computer simulation if its of any help: http://casa.colorado.edu/~ajsh/schw.shtml