Theories on beginnings of black holes

Black holes have three observable properties: mass, rotation rate and charge. Up until now we have only been able to determine the mass of suspected black holes. There is a relationship known as Kepler's third law which relates orbital speed, distance and force of gravity due to mass. So far this as been our only evidence for black holes: we see gas rotating fast in a tight circle which can only be explained as a black hole.

Near the center of our galaxy we see the effects of a black hole about 1 million times the mass of our sun. But recently, astronomers have noted even faster gas near the center of our galaxy which only be explained if the black hole is rotating. As black holes rotate they actually drag the space-time continuum around with it causing the gas to rotate faster than normal. For gas to rotate this fast near our black hole it should already have been sucked in. The only other explanation is that the black hole is rotating. It appears we have observed two of the three detectable properties of black holes. When a theory makes predictions that are latter observed, it gives us great confidence that our theories are correct. That is how science works.

It appears that so many other galaxies also have black holes at their centers that astronomers are beginning to believe that all galaxies might have black holes at their centers. Some argue that black holes may have been originally created during the big bang. They might have been the seeds around which galaxies formed. As the black holes attracted gas and matter towards them and began to rotate, the gas and dust flattened into a disk and gave us the spiral galaxies we see today.

The Milky Way still looms overhead and you can easily make out the dust lanes from dark sites during this dry, cool weather. Sagittarius (looks like a teapot to me) is low in the south and the Milky Way looks like steam escaping the spout and finally free to claim the nigh sky.

The bright star Fomalhaut is low in the southeast and should twinkle and change colors as it is low in the sky and must travel through many layers of atmosphere before it reaches our eyes. The Big Dipper is falling into the northwestern horizon and we will soon be without its companionship for a few months. Mars continues as the brightest object in the sky at sunset. Its ruby red glow can be seen low in the south.

Saturn rises about two hours after sunset in the beginning of the month and at sunset toward the end. Next month Saturn will be in prime observing position. Jupiter lags behind Saturn a couple of hours and will be positioned best for viewing near dawn. Venus has been greeting early morning risers this last month and this continues for October. For 11 days near the end of the month, Venus has a close, fainter companion, Mercury, which should be easily seen just to the north.

The observatory at Southeast Missouri State University is nearing its end. As we prepare for the new interchange for Interstate 55 in Jackson, Mo., the university has plans to convert its farm into a technology park. The recent build-up of billboards with bright lights has also contaminated the site with excess light pollution. We are having trouble finding a new site. We only need about one acre but it needs to be within 30 minutes of the university with dark skies. If you have any suggestions, please let me know. Share the night.

Dr. Michael Cobb is a professor of physics at Southeast Missouri State University.