Our Sun is a normal main-sequence G2 star, one of more than 100billion stars in our galaxy. The Sun is by far the largest object in the solar system. It contains more than 99.8% of the total mass of the Solar System (Jupiter contains most of the rest).

R. Michael Barnett of the Lawrence Berkeley National Laboratory and Helen Quinn of the Stanford Linear Accelerator Center offer this answer, portions of which are paraphrased from their book The Charm of Strange Quarks: In 1930 Paul Dirac formulated a quantum theory for the motion of electrons in electric and magnetic fields, the first theory that correctly included Einstein's theory of special relativity in this context.

Short answer: no. If you've read or heard that the star Belelgeuse might explode in a few weeks or a few months - that it will temporarily add a second sun to Earth's sky and somehow also possibly prove the world will end in 2012 (to which we can only say, "huh?") - you might want to find more reliable sources.

NOTE: This section is about stellar-mass black holes. For information about black holes that measure in the billions of solar masses, seeActive Galaxies & Quasars . There are many popular myths concerning black holes, many of them perpetuated by Hollywood.