They observe the X-rays emitted, I've seen several "pictures" of blackholes.
In fact, I even have a jpg of a radio galaxy ("super" blackhole) on my Mac.
If you don't believe me, I can always email =p
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tear it down / AIM: G2uidehatr
Obviously, black holes can't be observed directly, using modern methods. But the effect they have on the surrounding space-time can be easily observed. Also, since black holes do emit particals, this can be observed as well.
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Elimi-Nation wrote:
Are white holes = to particle fountains?
In theory, yes it could be thought of as a partical fountain.
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Soviet mikee wrote:
The Greeks? Oh yea, who needs radio-telescopes and hubble when you have....
math and glass telescopes 
Hmm, 'math and glass telescopes' managed to calculate the circumfrance of the earth almost EXACTLY. Pretty damn good for an ancient civilization if you ask me. So i wouldn't put finding a 10th planet too far past them.
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NightHawk The Sane
(url="http://"mailto:nighthawk@eego.net")mailto:nighthawk@eego.net(/url)nighthawk@eego.net
To calculate the circumference of the earth the greeks didn't use a telescope, a
mathematician ( i think Pythagor) used the shadow of a big tower and trigonometric formulas. Angle of the sun, the height of the tower, how long the shadow, and some other things.
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I'll Eliminat u!
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NightHawk The Sane wrote:
**Hmm, 'math and glass telescopes' managed to calculate the circumfrance of the earth almost EXACTLY. Pretty damn good for an ancient civilization if you ask me. So i wouldn't put finding a 10th planet too far past them.
**
Mmm, duh. Greeks used simple trig to find to circumference of the earth. But this is not an example of technology replacing math. That is to say, modern civilization found X by using technology while the Greeks found X using math.
The tenth planet would be so far away no amount of calculations could of proved it was there. Neptune and Pluto for example, were not first found by using telescopes, but rather by observing the planets before them. Upon looking at Uranus, astronomers noticed there was a something 'tugging' on it. So they new there was something out there and where to look. Now, Uranus is viewable using glass telescops, so perhaps the Greeks could of figured out there was another planet. However, Neptune and Pluto are beyond the reach of many 'modern' (home) telescopes today.
Thus, finding Pluto would be impossible and finding another planet would be out of the question. We have hubble, we can see and compare the "inner and outer" portions of the Universe (thats how the theory of a expanding and contracting Universe was shot down). We have also found many other solar systems.
There ain't no tenth planet, just the out skirts of the solar system.
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tear it down / AIM: G2uidehatr
I just wanted to say, it is not possible for black holes to have infinite gravity, as that would push the gravity well of the black hole to an infinite size, which would suck the entire universe into it.
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Meddle not in the affairs of dragons, for you are cruchy and taste good with catsup.
By using the example of the circumfrence of the earth, I was merely showing how the Greeks were well advanced in math/science and that they had found things about our world that we used 'hi-tech' gizmos to prove.
As for the 10th planet, in the 6 monthes or so, there have been a few people who claimed to have found a planet beyond pluto. The existace has not been proven or disproven yet.
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NightHawk The Sane
(url="http://"mailto:nighthawk@eego.net")mailto:nighthawk@eego.net(/url)nighthawk@eego.net
