The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye.
Our universe is about 13.8 billion years old, so most galaxies formed when the universe was quite young! Astronomers believe that our own Milky Way galaxy is approximately 13.6 billion years old. The newest galaxy we know of formed only about 500 million years ago.
SETTING NEW RECORDS, the James Webb Space Telescope has discovered the oldest known galaxy known to the universe and humankind. Caught and snapped in the cosmos, the GLASS-z13 galaxy was formed just 300 million years after the Big Bang, which struck 13.8 billion years ago.
Based on the age of the universe — about 13.7 billion years — that makes our galaxy roughly 13.6 billion years old. Given this age, it's completely possible for collisions with other galaxies to have occurred 8 billion to 10 billion years ago, before our 4.6 billion-year-old solar system had begun forming.
In 2000, scientists looked to date what they thought was the oldest star in the universe. They made observations via the European Space Agency's (ESA) (opens in new tab) Hipparcos satellite and estimated that HD140283 — or Methuselah as it's commonly known — was a staggering 16 billion years old.
The earliest life forms we know of were microscopic organisms (microbes) that left signals of their presence in rocks about 3.7 billion years old.
In a new study, Stanford physicists Andrei Linde and Vitaly Vanchurin have calculated the number of all possible universes, coming up with an answer of 10^10^16.
Our Milky Way will have lost its identity long ago through merging with the Andromeda galaxy, M31. The resulting giant elliptical galaxy will be devoid of dust and gas. The night sky will be a largely homogeneous sprinkling of stars. Stellar density will concentrate toward the galactic core.
There's a limit to how much of the universe we can see. 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).
By multiplying this number by the number of times this tiny patch of sky would fit into the entire sky, astronomers came up with an estimate of between about 100 and 200 billion galaxies.
In the beginning, there was an infinitely dense, tiny ball of matter. Then, it all went bang, giving rise to the atoms, molecules, stars and galaxies we see today.
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.
Approximately five billion years from now, or 19 billion years after the Big Bang, the Milky Way and the Andromeda Galaxy will collide with one another and merge into one large galaxy based on current evidence (see, Andromeda–Milky Way collision.)
Are there any dead galaxies? The Hubble Space Telescope has found not one or two, but as many as 6 galaxies that are dead, as far as their role of birthing stars is concerned. The Hubble Telescope was looking back in time to a period when the universe was some 3 billion years old.
There are likely to be many more planetary systems out there waiting to be discovered! Our Sun is just one of about 200 billion stars in our galaxy.
At more than 13 billion years old, the black hole and quasar are the earliest yet seen, giving astronomers insight into the formation of massive galaxies in the early universe.
Even though certain features of the universe seem to require the existence of a multiverse, nothing has been directly observed that suggests it actually exists. So far, the evidence supporting the idea of a multiverse is purely theoretical, and in some cases, philosophical.
Eventually, the entire contents of the universe will be crushed together into an impossibly tiny space – a singularity, like a reverse Big Bang. Different scientists give different estimates of when this contraction phase might begin. It could be billions of years away yet.
No, they don't believe there's an end to space. However, we can only see a certain volume of all that's out there. Since the universe is 13.8 billion years old, light from a galaxy more than 13.8 billion light-years away hasn't had time to reach us yet, so we have no way of knowing such a galaxy exists.
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.
Galaxies may exist at that distance, but their light would be too faint for our telescopes to see. C. Because looking 15 billion light-years away means looking to a time before the universe existed.
Our Milky Way galaxy is destined to collide with our closest large neighbour, the Andromeda galaxy, in about five billion years. Scientists can predict what's going to happen. The merger will totally alter the night sky over Earth but will likely leave the solar system unharmed, according to NASA.
No, the universe contains all solar systems, and galaxies. Our Sun is just one star among the hundreds of billions of stars in our Milky Way Galaxy, and the universe is made up of all the galaxies – billions of them.
Our universe is also called the cosmos. It is originally a greek word. In early days it was thought that our Galaxy constituted the entire universe.
The world as we know it has three dimensions of space—length, width and depth—and one dimension of time. But there's the mind-bending possibility that many more dimensions exist out there. According to string theory, one of the leading physics model of the last half century, the universe operates with 10 dimensions.