Friday, November 02, 2007

...at least I understand something about black holes

Ok, so change of topic.

Science.

I was thinking today and wondering how moons and other objects are able to stay adrift in space with just enough acceleration to keep from getting sucked towards a planet, but not enough acceleration to escape its gravitational pull. Then I thought, wouldn't it be cool if the earth could act as a huge magnifier, pulling light ever so slightly towards it, therefore creating a point where this light would meet back up and like be slightly stronger than normal light.

Ok, so I probably lost you there. So then I thought about black holes. Light is both a wave and a particle, and a black hole, to my understanding, is basically a really, reallly compressed planet, sucking in light that comes at it. Now what if this light is able to act as a satellite? If light traveled at just the correct angle across just the right distance from a black hole with just the right mass, the light would therefore be caught in the black hole's field of gravity, spinning around and around the black hole just as Saturn's rings spin around Saturn.


Alright. Now what?

Hmm.

"You dream it as you tell it, hoping others might dream along with you"
Tim O'Brien

6 comments:

Anonymous said...

Saturn's rings are made of rocks, not light. Also, black holes aren't really compressed planets, they are simply a spot in space with an immense gravitational pull. Technically they can be a very dense object, whose pull is so great it sucks everything in, but even if light passed at the correct angle, it wouldn't satellite around it forever, it would eventually be drawn in by the gravitational field or would manage to escape. The light would be too unstable around such a strong pull. They have explanations of this in tons of textbooks.

Mike said...

"As it turns out, it is possible for radiation to orbit a black hole. For a nonrotating black hole, radiation traveling at the speed of light can orbit in circular orbits with a radius that is 1.5 times the horizon radius, although the orbits are very unstable. That is, if the orbital parameters aren’t perfectly adjusted, the photons either fall into the black hole or escape. Even if a photon had the perfect trajectory to place it into such an orbit, the gravitational pull of other nearby objects would nudge it enough that it wouldn’t stay there."

An answer from a physicist at the University of Richmond. I was so interested in this, I actually emailed someone who like knew this stuff.

Anonymous said...

look at your own quote.

the orbits are "very unstable", and eventually "gravitational pull of other nearby objects would nudge it enough that it wouldn’t stay there". So basically, light can orbit a black hole but not forever, eventually being drawn in or escaping since it's too unstable, which is pretty much exactly what I said earlier.

Mike said...

I agree, you were right. I was just trying to elaborate.

Anonymous said...

oh and also the moon has been pulling farther and farther away from earth over the past millions of years because it is slowly escaping its gravitational pull. So I guess its acceleration is slowly but surely winning. just a cool factoid.

Mike said...

Coolio. I always wondered how the moon is like staying within like the same distance of earth. I guess it's not. So would that would then mean that if we had enough horizontal acceleration, we could escape earth's gravity. *puts on jet packs*.

Hmmm...so then the moon circles the earth every 29 days or so...and it is 250,000 miles from the earth to the moon..the moons path thereofre has a circumference of 1570795 miles...so therefore the moon must be traveling at about 37.5 miles per minute. That's prettty fast. Then if you get closer to the earth...lol...I'm gonna need some big jet packs.