Dark Matter, Triton, the eating habits of black holes and rogue black holes

9 Jun 2011

At http://www.technologyreview.com/blog/arxiv June 8th, there is a post on Dark Matter - the invisible stuff that is thought to fill the universe. It refuses to interact with light - and cannot be seen by optical instruments, does not reflect, emit, or absorb light. However, one garoup of scientists say they can see dark matter - searching for it in deep mines in Europe and North America. Rather, they think they have discovered a heartbeat - that may be dark matter. This post looks at the subject with a somewhat cynical eye (unlike www.physorg.com/print226654570.html ) as far as the experiments are concerned as some physicists are themselves critical. The blogger suggests the experiment is beginning to have something of fashion about it - what was dismissed a couple of years ago is now attracting attention.

At the same blog there is a story about radio telescopes looking at cosmic magnetic fields, and another post on Triton, a moon of Neptune that has a retrograde orbit. Many smaller moons of Jupiter, Saturn and Uranus also have a retrograde orbit, attributed to capture. Triton is somewhat different he says as it is one of the largest moons in the solar system. It is also geologically active.

At www.sciencedaily.com/releases/2011/06/110606092731.htm ... astrophysicists studying x-rays emitted where super heated gases are thought to plunge into distant black holes say they emit tremendous amounts of energy which can escape as visible light, ultrviolet light, and as x-rays. This energy can also drive outflows of gas and dust far from the hypothetical black holes. An interesting piece on current thinking - how to make the theory fit the facts of observation (the paper is published in the June 3rd issue of The Astrophysical Journal). It is an exercise in how to explain the differences between observation and theory.

However, at www.sciencedaily.com/releases/2011/06/110607094515.htm the dark matter experiment in a deep mine in Minnesota are described in more detail - where dark matter has diversified into Wimps (weakly interacting massive particles). Meanwhile, at www.dailygalaxy.com/my_weblog/2011/06/millions-of-rogue-black-holes-in-t... ... implying they might have an appetite for our sun. In this posting we learn that the Milky Way galaxy may be full of rampant but phantom planet eating black holes - all down to a computer simulation. Rogue black holes would be difficult to spot, it seems, even if we looked for them, according to one astronomer quoted. They might be detected by observing how super strength gravitational fields bend the light - said to be observable when the background stars appear to shift and brighten momentarily.