Dark Matter, Dark Energy
 

I'm posting this here because it is so new and is reflective of many of the questions that are floating around right now.

We can't see it, but we can see its effects.

http://news.bbc.co.uk/1/hi/wales/south_east/4288633.stm

Astronomers say they have discovered an object that appears to be an invisible galaxy made almost entirely of dark matter.

The team, led by Cardiff University, claimed it is the first to be detected.

A dark galaxy is an area in the Universe containing a large amount of mass that rotates like a galaxy, but contains no stars.

It was found 50 million light years away using radio telescopes in Cheshire and Puerto Rico.

The unknown material that is thought to hold these dark galaxies together is known as 'dark matter', but scientists still know very little about what that is.

let's send things into it! *jumps up and down*

One problem, it's not a black whole.

You could probably drive right by it and not notice.

Good example of an unseen phenomena deduced by the application of the scientific method, Troubleshooter!

Physicists and astronomers had to come up with an explanation for the difference between the observed luminousity of a region of space versus the gravitational field generated in that same region. Going by luminousity alone, we shouldn't observe the configurations of galaxies and stars that we actually do. The ratio of luminosity to an object's gravitational field is such that these clusters should be flying apart - not staying together. About 50 years ago a guy named Fritz Zwicky finally figured out that galaxies consist predominantly of matter in some nonluminous form -"dark matter."

There are several theories about the nature of the particles which make up this dark matter. Cosmologists look to the conditions which existed in the early universe for possible models. Likely relics of the early universe are species of stable, weakly interacting particles. One example is the neutrino, if it possesses a small mass. Normally, the neutrino is assumed to be practically massless, but a finite mass is not implausible.

Another possibility is a very massive particle (more mass than a proton!). These particles have been given the acronym WIMP: for weakly interacting, massive particle. Exotic WIMPs such as the photino have been theorized to exist in enough quantity to close the universe. The problem is that there is no guarantee that these particles DO exist. Disregarding this uncertainty, the big bang theory predicts their density today, if they do exist and are stable over the age of the universe. (and you wonder why I choose to live in a black box! :D )

Anyhow, I could go on, but I'm starting to detect that glazed look among the members of the audience and I have a bad cold which needs to be taken to bed with a bottle of brandy. ;)

The least you could do is take it out for a nice dinner first.

Or somebody needs a new grant or its back to working for a living. :worried:

Sometimes, I think my grey matter may :confused: be that far away. Sorry, need to get my telescope out and see if I can find it..... Get back with you (if) I find it......