As far as we can tell, there is no edge to the universe. Space spreads out infinitely in all directions. Furthermore, galaxies fill all of the space through-out the entire infinite universe.
One thing's for sure: the Universe does not have an edge. There's no physical boundary – no wall, no border, no fence around the edges of the cosmos. This doesn't necessarily mean that the Universe is infinitely large though.
The Hercules–Corona Borealis Great Wall or simply the Great Wall is the largest known structure in the observable universe, measuring approximately 10 billion light-years in length (the observable universe is about 93 billion light-years in diameter).
In actual fact, there is no purple band of 'negative energy' surrounding the rim of the Milky Way called the Galactic Barrier. However, the Milky Way is surrounded by the Galactic Halo, comprising of dark matter, star clusters, clouds of gas and a few lone old stars.
In cosmology, galaxy filaments are the largest known structures in the universe, consisting of walls of gravitationally bound galactic superclusters. These massive, thread-like formations can reach 80 megaparsecs h−1 (or of the order of 160 to 260 million light-years) and form the boundaries between voids.
The trite answer is that both space and time were created at the big bang about 14 billion years ago, so there is nothing beyond the universe. However, much of the universe exists beyond the observable universe, which is maybe about 90 billion light years across.
Our universe has no edge or boundary - there is no 'outside' of our universe (see question 1). It is possible that our universe is part of an infinity of universes (see question 5), but these universes do not necessarily need a 'space' to exist in.
Cosmologists aren't sure if the universe is infinitely big or just extremely large. To measure the universe, astronomers instead look at its curvature. The geometric curve on large scales of the universe tells us about its overall shape. If the universe is perfectly geometrically flat, then it can be infinite.
Yes, a star can end up hurled out of a galaxy after approaching a black hole on a trajectory that accelerates it above the galaxy's escape velocity.
No, no has ever gone out of our Milky way galaxy (not sure about Aliens). The Milky Way is about 1,000,000,000,000,000,000 km ( about 100,000 light years or about 30 kpc) across. And we live on Earth in Solar System in Orion Spiral Arm, Milky Way Galaxy.
As it stands, the universe is the largest object that we are aware of. There is nothing larger, and everything we can smell, hear, taste, touch, or see is a part of it.
So far, the evidence supporting the idea of a multiverse is purely theoretical, and in some cases, philosophical. Some experts argue that it may be a grand cosmic coincidence that the big bang forged a perfectly balanced universe that is just right for our existence.
Thanks to dark energy and the accelerated expansion of the Universe, it's physically impossible to even reach all the way to the edge of today's observable Universe; we can only get a third of the way there at maximum.
As a universe, a vast collection of animate and inanimate objects, time is infinite. Even if there was a beginning, and there might be a big bang end, it won't really be an end. The energy left behind will become something else; the end will be a beginning.
The observable universe is finite in that it hasn't existed forever. It extends 46 billion light years in every direction from us. (While our universe is 13.8 billion years old, the observable universe reaches further since the universe is expanding).
There is a cosmic horizon that limits how far we can travel through the expanding Universe, and for objects more than ~18 billion light-years away at present, they're already effectively gone.
The technology required to travel between galaxies is far beyond humanity's present capabilities, and currently only the subject of speculation, hypothesis, and science fiction. However, theoretically speaking, there is nothing to conclusively indicate that intergalactic travel is impossible.
As galaxies fall through clusters, the intergalactic plasma can rapidly remove their gas in a violent process called ram pressure stripping. When you remove the fuel for star formation, you effectively kill the galaxy, turning it into a dead object in which no new stars are formed.
So, to leave our Galaxy, we would have to travel about 500 light-years vertically, or about 25,000 light-years away from the galactic centre. We'd need to go much further to escape the 'halo' of diffuse gas, old stars and globular clusters that surrounds the Milky Way's stellar disk.
22 billion years in the future is the earliest possible end of the Universe in the Big Rip scenario, assuming a model of dark energy with w = −1.5. False vacuum decay may occur in 20 to 30 billion years if the Higgs field is metastable.
It appears that space was created in the Big Bang, 13.8 billion years ago and has been expanding ever since. The overall shape of space is not known, but space is known to be expanding very rapidly due to the cosmic inflation.
No, there isn't sound in space.
This is because sound travels through the vibration of particles, and space is a vacuum. On Earth, sound mainly travels to your ears by way of vibrating air molecules, but in near-empty regions of space there are no (or very, very few) particles to vibrate – so no sound.
Time travel to the past is theoretically possible in certain general relativity spacetime geometries that permit traveling faster than the speed of light, such as cosmic strings, traversable wormholes, and Alcubierre drives.
We are very intimately connected with the rest of the universe in a very practical way. Our bodies actually do contain atoms that were forged in stars.
Far outside our solar system and out past the distant reaches of our galaxy—in the vast nothingness of space—the distance between gas and dust particles grows, limiting their ability to transfer heat. Temperatures in these vacuous regions can plummet to about -455 degrees Fahrenheit (2.7 kelvin). Are you shivering yet?