What is the Universe? - NASA Science
The universe contains all the energy and matter there is. Much of the observable matter in the universe takes the form of individual atoms of hydrogen, which is the simplest atomic element, made of only a proton and an electron (if the atom also contains a neutron, it …
What is the universe? - Live Science
2022年5月3日 · The universe is literally everything, the sum of all existence. It includes all matter, like stars and galaxies. The universe also includes all radiation and all other forms of energy.
Universe | Definition & Facts | Britannica
2024年12月16日 · universe, the whole cosmic system of matter and energy of which Earth, and therefore the human race, is a part. Humanity has traveled a long road since societies imagined Earth, the Sun, and the Moon as the main objects of creation, with the rest of the universe being formed almost as an afterthought.
Universe - NASA Science
Discover the universe: Learn about the history of the cosmos, what it's made of, and so much more. Worlds beyond our solar system. In 2005, NASA’s Spitzer mapped a ring of dust around Vega, one of the brightest stars in the northern sky.
The Universe | Facts, Information, History & Definition - The Nine Planets
2020年8月19日 · However, the observable universe is around 93 billion light-years with a radius of around 46.5 billion light-years. The universe’s density is equivalent to 5 protons per cubic meter of space. The universe is made up of 4.9% ordinary (baryonic) matter, 26.8% dark matter, and 68.3% dark energy.
Overview - NASA Science
New ideas and major discoveries made during the 20th century transformed cosmology – the term for the way we conceptualize and study the universe – although much remains unknown. Here is the history of the universe according to cosmologists’ current theories.
Universe Facts - Space Facts
The universe is the sum total of all the planetary systems, stars, nebulae, galaxies, galactic clusters, black holes, and the atoms and molecules that make all these objects. It also contains all the energy we know about, along with dark matter, which has not been directly observed.
Universe | HubbleSite
2023年6月2日 · By allowing scientists to study the origins of the universe, the earliest galaxies and the mysterious, repulsive force known as dark energy, Hubble is helping to answer age-old questions such as Where did we come from? and How …
The Universe - Universe Today
2017年5月11日 · So what is the Universe? Well, the short answer is that it is the sum total of all existence. It is the entirety of time, space, matter and energy that began expanding some 13.8 billion...
Is there anything beyond the universe? | Space
2022年2月25日 · To answer the question of what's outside the universe, we first need to define exactly what we mean by "universe." If you take it to mean literally all the things that could...
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