Scientists using the Hubble Space Telescope announced January 13 that they believe that black holes, once considered only theoretical objects, may exist in the hearts of most galaxies.
     The team of astronomers, led by Doug Richstone of the University of Michigan, used the Hubble Space Telescope and a ground-based telescope to survey 27 nearby galaxies, and found evidence of supermassive black holes in many of them.
     These results have led them to believe that supermassive black holes may be found in most galaxies, and that these black holes have once powered quasars, the mysterious bright objects believed to be the superluminous cores of extremely distant and ancient galaxies.
     "We believe we are looking at 'fossil quasars' and that most galaxies at one time burned brightly as a quasar," Richstone said.
     The results are consistent with previous HST observations, which have shown quasars dwelling in a wide variety of galaxies. The reason why black holes are so abundant, or why the mass of the black holes is directly proportional to the mass of the galaxy it is, is yet unknown.

A solar physicist has found evidence of giant bumps -- or mountains -- on the surface of the Sun, based on observations from a joint European-American spacecraft.
     Jeffrey Kuhn of Michigan State University found 60 such "mountains" on the surface of the sun in data provided by a Doppler imager on the Solar and Heliospheric Observatory (SOHO), a satellite launched in December 1995.
     Each mountain is only half a kilometer (0.3 mi.) tall, but extends for up to 65,000 km (40,000 mi.) on the surface of the Sun, according to Kuhn.
     Kuhn believes that the Sun's intense magnetic field -- 1,000 times stronger than the Earth's -- "threads the surface of the Sun" and creates the bumps of hot gas seen by the satellite.
     Kuhn told UPI that the satellite is providing new information on the 11-year solar cycle, which may permit a better understanding of the effects the cycle has on the Earth's climate.

A set of asteroids that travel around the Sun in the same orbit as the planet Jupiter may be in less stable orbits than once thought, providing yet another hazard to the Earth.
     Astronomers Hal Levinson of the Southwest Research Institute and Carolyn and Eugene Shoemaker studied nearly 200 Trojan asteroids that orbit the Sun in two groups, one sixty degrees ahead of Jupiter and the other sixty degrees behind Jupiter.
     While they expected the asteroids to be relatively stable over long time periods, over a tenth of asteroids wandered away from the Trojans over a four-billion-year period.
     Some of these would later be ejected out of the solar system by gravitational interactions with Jupiter or other planets, but some would enter the inner solar system and possibly threaten the Earth and other inner planets.