A dark matter halo is a hypothetical component of a galaxy that envelops the galactic disk and extends well beyond the edge of the visible galaxy. The halo's mass dominates the total mass. Since they consist of dark matter, halos cannot be observed directly, but their existence is inferred through their effects on the motions of stars and gas in galaxies. Dark matter halos play a key role in current models of galaxy formation and evolution.
Read more about Dark Matter Halo: Rotation Curves As Evidence of A Dark Matter Halo, Theories About The Nature of Dark Matter, Milky Way Dark Matter Halo
Famous quotes containing the words dark, matter and/or halo:
“The woods are lovely, dark and deep.
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep.”
—Robert Frost (1874–1963)
“It doesn’t matter that your painting is small. Kopecks are also small, but when a lot are put together they make a ruble. Each painting displayed in a gallery and each good book that makes it into a library, no matter how small they may be, serves a great cause: accretion of the national wealth.”
—Anton Pavlovich Chekhov (1860–1904)
“Most books belong to the house and street only, and in the fields their leaves feel very thin. They are bare and obvious, and have no halo nor haze about them. Nature lies far and fair behind them all. But this, as it proceeds from, so it addresses, what is deepest and most abiding in man. It belongs to the noontide of the day, the midsummer of the year, and after the snows have melted, and the waters evaporated in the spring, still its truth speaks freshly to our experience.”
—Henry David Thoreau (1817–1862)