Thursday, March 25, 2010

Interesting facts about dark matter

Since dark matter is invisible to human eye it can only be detected through its gravitational influence on its surroundings. Basically, it is really difficult for us to comprehend that 23 percent of known universe is made up of this mysterious dark matter (23% dark matter vs. just over 4% of visible matter with the rest being the mysterious dark energy)

When the universe was still young clumps of dark matter have likely attracted gas, which then coalesced into stars that eventually assembled the today's galaxies.

Black holes absorb dark matter, and over the billions of years since galaxies were first formed, this absorption of dark matter in black holes has very likely altered the population of galaxies from what we can observe today.

Some scientists believe that the density of dark matter in the centers of galaxies is likely to be a constant value.

Dark matter is non-interactive with light, but it interacts with ordinary matter via gravity.

Despite the recent improvement in astronomy, there is still a great deal of unknown about origin, properties and distribution of dark matter in the universe.

Dark matter is an misterious energy that contains most of the Universe's mass. This concept was used for the first time by Fritz Zwicky in 1933.

The density of the dark matter in a galaxy has its maximum in the center and it gradually decreases as it gets to the outermost part, but the same process significantly increases the total size of the galaxy.

Determining the nature of dark matter is one one of the most important challenges in cosmology that attracts many scientists.

Dark matter makes up roughly 85 percent of the matter in the universe.

The dark matter seems to comprehend how the visible matter is distributed. They seem to conspire with each other such that the gravity of the visible matter at the characteristic radius of the dark halo is always the same.

Dark matter is believed to be present within and around the Milky Way, in the form of a halo.

Methods for detecting dark matter include direct and indirect detection methods, which cannot be directly observed since it does not emit radiation. The former include simultaneous light and heat detection, simultaneous heat and ionization detection, and simultaneous light and ionization detection, such as research into distinctive signals (the most famous being the search for an annual modulation in the dark matter signal caused by the orbiting of the Earth).

Indirect detection methods do not directly seek the dark matter particles but researchers try to identify other particles, (neutrinos, photons, etc.), produced when the Universe's dark matter particles are destroyed.