The existence of Dark Matter has long been argued but new evidence from the Hubble Space Telescope insists Dark Matter is real. Dark Matter is a tricky thing to research because it is invisible, so the only way to get a handle on if it’s real or not is to observe its interaction on normal matter. This is where Hubble comes in. It recently took a photo of the Perseus galaxy cluster and determined that four dwarf galaxies appear completely untouched by the massive amount of gravitational turmoil in that region, gravitational turmoil that is literally ripping neighboring galaxies apart.

Hence, something is protecting these ancient dwarf galaxies that isn’t protecting spiral galaxies. Theory? Dwarf galaxies have a much thicker shield of Dark Matter than spiral galaxies.

From Live Science:

First proposed about 80 years ago, dark matter is thought to be the “glue” that holds galaxies together. Astronomers suggest that dark matter provides vital “scaffolding” for the universe, forming a framework for the formation of galaxies through gravitational attraction.

Previous studies with Hubble and NASA’s Chandra X-ray Observatory found evidence of dark matter in entire clusters of galaxies such as the Bullet Cluster. The new Hubble observations continue the search for dark matter in individual galaxies.

Because dark matter cannot be seen, astronomers detect its presence through indirect evidence. The most common method is by measuring the velocities of individual stars or groups of stars as they move randomly in the galaxy or as they rotate around the galaxy. But the Perseus Cluster is too far away for telescopes to resolve individual stars and measure their motions.

Yesterday, the Dark Matter collaboration made an announcement in Venice, Italy that claimed dark matter, the elusive particle that theoretically accounts for 90% of the universe, had been detected on Earth.

The DAMA experiment has looked more directly for dark matter particles hitting the Earth. The experiment takes place in an underground laboratorythat lies beneath 1.4 kilometers of rock, inside the Gran Sasso mountain in Italy. The team looks for flashes of light in a sodium iodide detector.
The flashes mainly come from background “noise”, such as ordinary neutrons from radioactivity in the surrounding rock. But some might also come from dark matter particles, and, if so, the scientists expect to see seasonal variations in the signal because the Earth’s speed through our galaxy changes depending on its direction of motion.

All is not settled though, as the method used in Italy has not been successfully reproduced anywhere else.

But Halzen is wary. “The discussion about whether this is some unknown systematic effect remains,” he says.
Richard Gaitskell from Brown University at Providence, Rhode Island, US, and a member of two dark matter experiments – the Cyrogenic Dark Matter Search(CDMS) and the Xenon project – also remains skeptical, because no other experiment has seen signs of dark matter.
“Right now, it is very difficult to reconcile theoretically what they are seeing and what we are seeing,” says Gaitskell.

Fight! Fight!