Galaxies+-+By+Jacob+M

=galaxies= tocthere are many types of galaxies like: spiral, disc, elliptical, irregular and barred galaxies. The milky way galaxy is a barred spiral galaxy with our solar system somewhere just outside the center of our galaxy putting us on the Orion arm. All of these galaxies are held together by one thing, gravity, this force is most likely from the giant bulge in the center of the galaxy, what gives it it's massive weight is not for sure but observational data suggests that supermassive black holes may exist at the center of many, if not all, galaxies.

==Life beyond Earth==

There are billions upon billions of galaxies in the universe, each with millions upon millions of stars and each of those stars have a couple of planets with the possibility of having life, and a small chance that these "aliens" are intelligent and capable of communicating with humans.

==Peculiar Galaxies==

Peculiar galaxies are galactic formations that develop unusual properties due to tidal interactions with other galaxies. An example of this is the ring galaxy, which possesses a ring-like structure of stars and interstellar medium surrounding a bare core. A ring galaxy is thought to occur when a smaller galaxy passes through the core of a spiral galaxy. Such an event may have affected the Andromeda Galaxy, as it displays a multi-ring-like structure when viewed in infrared radiation.

[[image:http://rst.gsfc.nasa.gov/Sect20/Izw18_hst_1c88.jpg width="314" height="244" align="left"]]Dwarf Galaxies
Despite the prominence of large elliptical and spiral galaxies, most galaxies in the universe appear to be dwarf galaxies. These tiny galaxies are about one hundredth the size of the Milky Way, containing only a few billion stars. Ultra-compact dwarf galaxies have recently been discovered that are only 100 parsecs (1 parsec = 3.262 lightyears) across instead of the usual 30 kiloparsecs (1 kiloparsec = 3,262 lightyears) Many dwarf galaxies may orbit a single larger galaxy the way that the Moon orbits the Earth.