Galaxies - NASA Science
Galaxies consist of stars, planets, and vast clouds of gas and dust, all bound together by gravity. The largest contain trillions of stars and can be more than a million light-years across. The smallest can contain a few thousand stars and span just a few hundred light-years.
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.
Stars and Galaxies | NASA Jet Propulsion Laboratory (JPL)
2021年1月12日 · Our universe includes a variety of astonishing and sometimes bizarre objects. Massive black holes so powerful, they swallow nearby objects. Galaxies that merge into giant swirls. Enormous stars that eventually explode and become supernovas. Neutron stars — objects so dense, one tablespoon of their material would weigh about 1 billion tons on Earth.
Solar System, Galaxy, Universe: What’s the Difference? - Science@NASA
2017年6月1日 · Many people are not clear about the difference between our Solar System, our Milky Way Galaxy, and the Universe. Let’s look at the basics. Our Solar System consists of our star, the Sun, and its orbiting planets (including Earth), along with numerous moons, asteroids, comet material, rocks, and dust.
Astronomy: Everything you need to know | Space
2023年7月25日 · Those who study astronomy explore the structure and origin of the universe including the stars, planets, galaxies and black holes that reside in it. Astronomers aim to answer fundamental...
ViewSpace
ViewSpace videos tell the stories of the planets, stars, galaxies, and universe, giving viewers the opportunity to experience space and Earth as seen with satellites and telescopes. Astronomy: Explore the sky with stories told through spectacular imagery from space telescopes.
What Is a Galaxy? | NASA Space Place – NASA Science for Kids
2024年12月5日 · A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems. A galaxy is held together by gravity. Our galaxy, the Milky Way, also has a supermassive black hole in the middle. When you look up at stars in the night sky, you’re seeing other stars in the Milky Way.
From dead galaxies to mysterious red dots, here's what the James …
17 小时之前 · Unusual chemistry in early galaxies. The early stars were the key building blocks of what eventually became life. The universe began with only hydrogen, helium and a small amount of lithium.
Galaxies, stars and planets | OpenLearn - Open University
2012年9月8日 · This free course, Galaxies, stars and planets, is a general introduction, including scale of the universe from the very large to the very small; orbits and gravity; the Solar System; the Sun and other stars; galaxies and the composition of astronomical objects.
Galaxies are cosmic islands of stars, planets, nebulas, gas, dust, and dark matter that are separated from one another in space but collectively help to tell the story of the universe. With the Hubble Space Telescope, we have begun to understand galaxies as …