From: Zardoz ®	04/11/2001 19:33:31
Subject: re: COSMOLOGY FAQ	post id: 484060
Does a black hole have greater gravitational attraction than the star from which it originated? From: B.C. . No, not unless it's sucked in matter on the way to becoming a black hole If there where a black hole between Mars and Earth would this effect the Earth in any way? From: Chris W (Avatar) A black hole orbiting the Sun between Earth and Mars would be felt. If it were a small mass (primordial) black hole then we may only see its effects as wobbles on planetary orbits that could not be explained by the visible bodies in the solar system. We would also be able to observe any transit of this body across the face of Mars, Jupiter etc if the alignment were right. If it were a black hole formed by solar collapse (>4 solar masses) then the Sun and the black hole would be a binary pair orbiting each other. I think it unlikely that the Earth's orbit would be viable/stable. If we go with a small black hole (say Earth mass - formed during the big bang) then we'd probably feel very little. At a distance, the black hole behaves the same way that a normal object of the same mass does. It may have a tiny effect on tides, but it'd more likely be swamped by the Moon's tides. We'd have a wonderful topic of study, and a way to test all sorts of theories regarding space-time curvature, event horizons, spaghetification etc. Such an object strikes me as being exceedingly unlikely. It'd have to be captured into solar orbit as it passed by.