German astronomers announced earlier this month that they had "all but confirmed" the existence of a massive black hole in the center of our own Milky Way galaxy.
     The team from the Max Planck Institute for Extraterrestrial Physics near Munich measured the proper motions of 39 stars near the galactic core to determine the nature of their movement around the core.
     The team found that the orbits were circular, which indicated that a large, massive object in the center. An irregular orbit would have revealed a less massive object in the core.
     The team estimates that the object has a mass 2.5 million times greater than our Sun. The object is near a powerful radio source named Sagittarius A+ and may in fact be that object, which lends additional evidence that the object is a black hole.
     The team leader, Reinhard Genzel, was still cautious about the claim, but he told Reuters that it was "caution backed up by the best evidence that has yet existed."
     "Our colleagues will take it as a very interesting new step but it has to be confirmed," Genzel added. "By early next year, if they don't find any problems, then it will be confirmed."
     Genzel's findings were published in the British journal Nature.

The subject of the Nobel Prize in physics, awarded to three Americans who found a new state of matter in supercooled helium, has implications for the formation of cosmic strings in the early moments after the Big Bang.
     The Nobel Prize was awarded to Professors David M. Lee and Robert C. Richardson of Cornell University and Professor Douglas D. Osheroff of Stanford University for their discovery of superfluidity in helium-3, an isotope of helium with only one neutron.
     The award was based on the discovery in the early 1970s of superfluidity by the three-man team. Osheroff was a graduate student of Lee and Richardson at the time of the discovery.
     When helium-3 is cooled to within a thousandth of a degree above absolute zero, the liquid helium changes phase to a more ordered form that lacks any internal friction. This liquid exhibits a number of unusual properties that can only be explained by quantum physics.
     The phase transitions in helium-3 may be analogous to certain attributes of cosmic strings, hypothesized structures formed early in the universe that may have been important to the formation of galaxies.
     Vortices that scientists formed in samples of helium-3 that here heated rapidly and locally and then cooled may resemble the vortices that formed into cosmic strings in the early moments of the universe. The vortices are not considered sufficient proof of cosmic strings, though, and require further theoretical research.

A brilliant meteor seen in the skies of the western U.S. on the evening of October 3 was likely a piece of an asteroid or comet, or even a piece of space junk, astronomers said.
     The meteor was seen from California to New Mexico at around 9pm PDT (4am GMT October 4). It was described by many as a long green streak bright enough to light up sky for several seconds.
     Hundreds of people contacted local authorities, believing the streak to be the result of a mid-air plane accident. The flash, however, took place too high to be possibly caused by a plane.
     John Mosley, an astronomer at the Griffith Park Observatory in Los Angeles, attributed the flash to a chunk of comet or asteroid material that burned up in the Earth's atmosphere. JPL officials added the possibility that the meteor was a piece of space junk reentering the Earth's atmosphere.
     No debris from the meteor was found on the ground.