What is the evidence in support of dark matter?

Answer 1

The evidence for Dark Matter is overwhelming; the real controversy in science lies in identifying what it is, as no-one actually knows for certain.

When we observe other galaxies, our understanding of gravity and general relativity tells us that object further from the centre of a galaxy should be moving more slowly than those much closer. This is analogous to the movement of planets in the solar system: we know that planets such as Neptune orbit the Sun more slowly than closer planets like Earth, as the Sun's gravity is not as strong at such distances.

However, when we look at galaxies, we see no such drop-off in orbital speed for stars that are further from the centre. If relativity is an accurate description of the way gravity works - and every experiment thus far has proved this indisputably - then there must be far more mass to a galaxy than we can perceive using the electromagnetic spectrum.

Answer 2

I'm going to star this question because I want to see what others say. I'm skeptical. I don't think there is any evidence.

Oh no ya don't, johnandeileen! You can't just tack black holes onto this thing in order to say it's real. We've known about black holes for a long time. Why would somebody come up with a NEW hypothesis which includes black holes as its only observable example? If what you say about galaxies is true, then I would be interested in seeing that evidence. Surely the data are posted somewhere on the Internet. All the computer simulations I've ever seen show the right kind of orbital speeds: fast at the center, slower as you go out. I just want to see a profile of a galaxy with the average measured red shifts at several different radii.

Answer 3

there is none really. there was a show on the science channel about a week or two ago, and everything they were saying about dark matter made no sense what so ever.
apparently, dark matter is some....well, something.....that is not made up of atoms or anything else we know of in our universe. scientists say it is undectable, so how CAN they know that it exists?
i have yet to hear any actual evidence supporting the theory of dark matter, so in my world; it does not exist.

Answer 4

A black hole is dark matter, the X rays emitted by gas being pulled from a nearby star is accepted proof of the existence of the black hole. It is accepted by the scientific community that there must be millions of cinder-like remains of cooled white dwarf stars, they too are dark matter. It is logical to believe that the universe is strewn with non reflecting bodies of all sizes and masses.