Darkness

In The Dark



Credit: NASA

Abell 85

We live in a dark envelope these last days of December. It is a returning subject of discussion among us "Northlings". Winter Solstice is just around the corner, 21st December the Sun 'will turn', as we say, most of us knowing the Sun actually does no such thing. Anyways, the important point is that we'll see more of the Sun from that day on.

The timing is thus perfect for discussing dark matters while we live through the darkest of times (of the year). With our minds focusing on the light to come we should remember that it is in fact a lot darker than we can imagine - even darker than on the North pole at Winter Solstice. SU's very own bigdirtymosh understands this and uses his space on the Discovery Channel to shed some light on the deep, deep, immense darkness out there.








Illustration: NASA/CXC/M.Weiss

Dark energy is estimated to contribute about 74% of the energy in the Universe, dark matter about 22% and normal matter about 4%. Only the normal matter can be directly detected with telescopes, which includes the hot gas emitted by galaxy clusters.