The Universe can be defined as everything that exists, everything that has existed, and everything that will exist. According to our current understanding, the Universe consists of space-time, forms of energy (including electromagnetic radiation and matter), and the physical laws that relate them. The Universe encompasses all of life, all of history, and some philosophers and scientists suggest that it even encompasses ideas such as mathematics and logic.
The Universe is all of time and space and its contents. It includes planets, moons, minor planets, stars, and galaxies, the contents of intergalactic space, and all matter and energy. The size of the entire Universe is unknown. It includes living things, planets, stars, galaxies, dust clouds, light, and even time. Before the birth of the Universe, time, space and matter did not exist.
The Universe contains billions of galaxies, each containing millions or billions of stars. The space between the stars and galaxies is largely empty. However, even places far from stars and planets contain scattered particles of dust or a few hydrogen atoms per cubic centimeter. Space is also filled with radiation (e.g. light and heat), magnetic fields and high energy particles (e.g. cosmic rays).
The Universe is incredibly huge. It would take a modern jet fighter more than a million years to reach the nearest star to the Sun. Travelling at the speed of light (300,000 km per second), it would take 100,000 years to cross our Milky Way galaxy alone.
No one knows the exact size of the Universe, because we cannot see the edge – if there is one. All we do know is that the visible Universe is at least 93 billion light years across. (A light year is the distance light travels in one year – about 9 trillion km.)
The Universe has not always been the same size. Scientists believe it began in a Big Bang, which took place nearly 14 billion years ago. Since then, the Universe has been expanding outward at very high speed. So the area of space we now see is billions of times bigger than it was when the Universe was very young. The galaxies are also moving further apart as the space between them expands.
The Universe is the cradle and source of all life existence. It is the totality of existence. This includes planets, stars, galaxies, the contents of intergalactic space, the smallest subatomic particles, and all matter and energy, the majority of which are most likely in the form of dark matter and dark energy. Universe is all existing matter and space considered as a whole; the cosmos. The universe is believed to be at least 10 billion light years in diameter and contains a vast number of galaxies; it has been expanding since its creation in the Big Bang about 13 billion years ago. It is a particular sphere of activity or experience. The “Parent Space” is the eternal, ever present cause of all — the incomprehensible deity, whose “invisible robes” are the mystic root of all matter, and of the Universe. Space is the one eternal thing that we can most easily imagine, immovable in its abstraction and uninfluenced by either the presence or absence in it of an objective Universe. It is without dimension, in every sense, and self-existent. Spirit is the first differentiation from that, the causeless cause of both Spirit and Matter. It is, as taught in the esoteric catechism, neither limitless void, nor conditioned fullness, but both. It was and ever will be.
The universe is created from a very high-frequency of the energy which when reaches a certain density explodes creating the same type of particle which are spinning, rotating around the centre with tremendous speed attracting other particles which materializing themselves, creates planets and stars, depending of the speed and strength of their frequencies.
Ninety percent of the mass in the universe is literally invisible to us. No light emanates from it and we cannot see it. Scientists know it is there because they are able to measure the gravitational pull these invisible masses exert on visible bodies. Not only that, but if we look at the entire spectrum of frequencies in the universe, man’s five senses can only pick up a very small amount of them.
Distances are so great that it takes the light from most stars years to reach us. When we look up we can never see what is going on now, we can only see what has already happened. Much is made of the assumption that the stars are so far apart that no beings could travel to another star in a single lifetime. The key factor of course, is time. However, time is a very complex subject. Here are some things you can begin to think about when it comes to considering time. These facts are well known by our physicists and based to a large degree on Einstein’s work.
Time is relative; it has nothing to do with distance. So stop making the assumption that it will take a certain amount of time to travel a certain distance. The two are completely unrelated.
Recent discoveries have shown that gas giant planets (similar to Jupiter) are common around other stars like the Sun. Though there is no conclusive evidence yet for potentially habitable, small, rocky planets like Earth, careful observations with more sensitive telescopes have detected a number of candidate terrestrial-like planets, larger than Earth. Many scientists believe these habitable worlds, in the so called “Goldilocks zone” where conditions are just right for life, must exist, and it’s only a matter of time before they are detected, either by inferred observations or potentially directly.
Remote sensing of young stars shows they are surrounded by dusty discs which contain the materials needed to form Earth-like planets.
The dusty discs that form around young stars are the sites where planets are made. The birth of a planet is thought to take a million years or more – much longer than a human lifetime – and it isn’t possible to watch an individual planet appear. Instead, the discs around many young stars must be observed in order to piece together the different parts of the formation process. Fortunately there are hundreds of these young stars within about 500 light years of the Sun, and many thousands more at greater distances.
If placed at 500 light years distance, our own Solar System would be about 1 arc second across – roughly equivalent to a thumb-tack seen from a mile away – so observations at high angular resolution are very important. Although planets forming in the habitable zone of Sun-like proto stars are currently far too small to be detected directly, the dust from which they form has a lot of surface area that intercepts starlight and converts the energy into heat which can be detected at short radio wavelengths.
The earliest scientific models of the Universe were developed by ancient Greek and Indian philosophers and were geocentric, placing the Earth at the center of the Universe. Over the centuries, more precise astronomical observations led Nicolaus Copernicus (1473–1543) to develop the heliocentric model with the Sun at the center of the Solar System. In developing the law of universal gravitation, Sir Isaac Newton (NS: 1643–1727) built upon Copernicus’s work as well as observations by Tycho Brahe (1546–1601) and Johannes Kepler’s (1571–1630) laws of planetary motion. Further observational improvements led to the realization that our Solar System is located in the Milky Way galaxy and is one of many solar systems and galaxies. It is assumed that galaxies are distributed uniformly and the same in all directions, meaning that the Universe has neither an edge nor a center. Discoveries in the early 20th century have suggested that the Universe had a beginning and that it is expanding at an increasing rate. The majority of mass in the Universe appears to exist in an unknown form called dark matter.
The Big Bang theory, the prevailing cosmological model describing the development of the Universe, states that space and time were created in the Big Bang and were given a fixed amount of energy and matter that becomes less dense as space expands. After the initial expansion, the Universe cooled, allowing the first subatomic particles to form and then simple atoms. Giant clouds later merged through gravity to form stars. Assuming that the standard model of the Big Bang theory is correct, the age of the Universe is measured to be 13.799±0.021 billion years.
There are many competing hypotheses about the ultimate fate of the Universe and about what, if anything, preceded the Big Bang, while other physicists and philosophers refuse to speculate, doubting that information about prior states will ever be accessible. Some physicists have suggested various multiverse hypotheses, in which the Universe might be one among many universes that likewise exist.
Scientists think that in the earliest moments of the universe, there was no structure to it to speak of, with matter and energy distributed nearly uniformly throughout. According to NASA, the gravitational pull of small fluctuations in the density of matter back then gave rise to the vast web-like structure of stars and emptiness seen today. Dense regions pulled in more and more matter through gravity, and the more massive they became, the more matter they could pull in through gravity, forming stars, galaxies and larger structures known as clusters, superclusters, filaments and walls, with “great walls” of thousands of galaxies reaching more than a billion light years in length. Less dense regions did not grow, evolving into area of seemingly empty space called voids.
Recently there has been ever more evidence that suggests most of the ingredients making up the universe come in forms that we cannot see.
It turns out that atoms only make up 4.6 percent of the universe. Of the remainder, 23 percent is made up of dark matter, which is likely composed of one or more species of subatomic particles that interact very weakly with ordinary matter, and 72 percent is made of dark energy, which apparently is driving the accelerating expansion of the universe.
The shape of the universe and whether or not it is finite or infinite in extent depends on the struggle between the rate of its expansion and the pull of gravity. The strength of the pull in question depends in part on the density of the matter in the universe.
If the density of the universe exceeds a specific critical value, then the universe is “closed” and “positive curved” like the surface of a sphere. This means light beams that are initially parallel will converge slowly, eventually cross and return back to their starting point, if the universe lasts long enough. If so, according to NASA, the universe is not infinite but has no end, just as the area on the surface of a sphere is not infinite but has no beginning or end to speak of. The universe will eventually stop expanding and start collapsing in on itself, the so-called “Big Crunch.”