A recent article in Physics.org “Missing Black Hole Report: Hundreds Found!” Oct 25, 2007 reported, “Astronomers have unmasked hundreds of black holes hiding deep inside dusty galaxies billions of light-years away. The (these) massive, growing black holes, discovered by NASA’s Spitzer and Chandra space telescopes, represent a large fraction of a long-sought missing population. Their discovery implies there were hundreds of millions of additional black holes growing in our young universe, more than doubling the total amount known at that distance.”
However, the only problem with assuming that all of these objects circled in blue are black holes is where are they now?
This question become harder to answer when one considers that according to all theoretical predictions, a black hole increases in size as it ages. Therefore, these massive black holes that existed when the universes was young should still exist today and be even more massive than they were back when they were first formed.
The above article points out that the circled object are visible because “of a doughnut-shaped cloud of gas and dust that surrounds and feeds a budding super massive black hole. As the gas and dust are devoured by the black hole, they heat up and shoot out X-rays. Those X-rays can be detected as a general glow in space, but often the quasars themselves can’t be seen directly because dust and gas blocks them from our view.”
However black holes are, by definition opaque to all forms of radiation which means they should be silhouetted against any emitted from behind them. Therefore, all black holes should be visible due to the shadows they cast in the background radiation in addition to “the gas and dust (they) are devouringâ€.
Additionally Einstein’s theories tell us that all mass creates gravitational forces, which bend or distorts light. This should make them visible even without a doughnut-shaped cloud of gas and dust that surrounding them. In fact, gravitational lensing is one of the methods that astrophysicists have used to detect black holes. (The video to the right shows the circular arcs of light observed by the Hubble Space Telescope which are generated by gravitational lensing of galaxies .)
This means that all black holes, even the ones that are not surrounded by gas should be detectable.
One problem with assuming that all of the objects circled in blue are black holes is that we should be able to observe many more than we do in other regions of the sky which are not surrounded by gas and dust through such techniques as gravitational lensing. The fact that we do not even with our advance observational technology such as that provided by the Hubble Space Telescope indicates that all the object circled in blue in the above picture many not be black holes.
We as scientists must be extremely careful not to let our personal beliefs interfere with our observational objectivity.
The above article mentioned, “The massive, growing black holes, discovered by NASA’s Spitzer and Chandra space telescopes, represent a large fraction of a long-sought missing population.
Is it possible the conclusion that the all objects circled in blue in the above picture are Black Holes is, in part because their existence supported their previous conclusion that the vast majority of black holes have not yet been observed?
Later Jeff
Copyright Jeffrey O’Callaghan 2007