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The Short Answer: A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems, all held together by gravity. A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems. A galaxy is held together by gravity.
How are galaxies defined?
Galaxies are sprawling systems of dust, gas, dark matter, and anywhere from a million to a trillion stars that are held together by gravity. Nearly all large galaxies are thought to also contain supermassive black holes at their centers.
What are 2 galaxies?
Closest galaxies Rank Galaxy Distance 1 Milky Way Galaxy 0 2 Canis Major Dwarf 0.025 Mly 3 Virgo Stellar Stream 0.030 Mly 4 Sagittarius Dwarf Elliptical Galaxy 0.081 Mly.
How do you determine a galaxy?
Astronomers can use what are called surface brightness fluctuations (SBF, for short), along with the color of a galaxy, to calculate how far away it is from earth. Most galaxies measured in this way are millions of light years away.
Are all stars in galaxies?
Answer: No, not all stars are in a galaxy. They may have once belonged to a galaxy, but they are not a part of it any more. Some of these so-called “stellar outcasts” or “intergalactic stars” have actually been observed by NASA’s Hubble Space Telescope.
What is the galaxy we live in?
We live in one of the arms of a large spiral galaxy called the Milky Way. The Sun and its planets (including Earth) lie in this quiet part of the galaxy, about half way out from the centre. 100 000 years to cross from one side to the other.
What is bigger than a galaxy?
From largest to smallest they are: Universe, galaxy, solar system, star, planet, moon and asteroid.
What happens if 2 galaxies collide?
The merging of galaxies will radically affect their shape. For example, two spiral galaxies can merge and form an elliptical galaxy. Sometimes even more than two galaxies can collide with each other. Merging galaxies can also trigger the creation of new stars.
What are the 4 types of galaxy?
Galaxies 101 The smallest of galaxies contain a “mere” few hundred million stars while the largest galaxies contain up to one hundred trillion stars! Scientists have been able to segment galaxies into 4 main types: spiral, elliptical, peculiar, and irregular.
How old is our galaxy?
Most galaxies are between 10 billion and 13.6 billion years old. 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.
What keeps a galaxy together?
Our galaxy, the Milky Way, is typical: it has hundreds of billions of stars, enough gas and dust to make billions more stars, and at least ten times as much dark matter as all the stars and gas put together. And it’s all held together by gravity.
What are the 3 types of galaxies?
Types of Galaxies Astronomers classify galaxies into three major categories: elliptical, spiral and irregular. These galaxies span a wide range of sizes, from dwarf galaxies containing as few as 100 million stars to giant galaxies with more than a trillion stars.
What is the most common type of galaxy?
What Are Elliptical Galaxies? Elliptical galaxies are the most abundant type of galaxies found in the universe but because of their age and dim qualities, they’re frequently outshone by younger, brighter collections of stars. Elliptical galaxies lack the swirling arms of their more well-known siblings, spiral galaxies.
Can a star exist outside a galaxy?
Yes, there are stars between galaxies. When there are collisions or interactions between galaxies, stars can be ripped out of the galaxies. These stars will then wander into space between galaxies.
Can a planet exist outside a galaxy?
An extragalactic planet, also known as an extragalactic exoplanet, is a star-bound planet or rogue planet located outside of the Milky Way Galaxy. This means that even galactic planets located farther than that distance have not been detected.
What galaxies can we see with your naked eyes?
The Andromeda Galaxy is the only other (besides the Milky Way) spiral galaxy we can see with the naked eye.
How many galaxies are in space?
While NASA previously determined that there were around two trillion galaxies in the universe, new findings say the number is more likely hundreds of billions. While NASA previously determined that there were around two trillion galaxies in the universe, new findings say the number is more likely hundreds of billions.
What is a galaxy class 6?
A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems, all held together by gravity. We live on a planet called Earth that is part of our solar system. A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems. A galaxy is held together by gravity.
Which arm of the Milky Way do we live in?
In recent decades, research advances have revealed that we live in our very own spiral arm of the galaxy, albeit a relatively minor one. Our spiral arm is formally called the Orion-Cygnus Arm. It’s also known simply as the Orion Arm or Local Arm, and you sometimes still hear the names Orion Bridge or Orion Spur.
What is the biggest thing in the Universe?
The largest known ‘object’ in the Universe is the Hercules-Corona Borealis Great Wall. This is a ‘galactic filament’, a vast cluster of galaxies bound together by gravity, and it’s estimated to be about 10 billion light-years across!.
Why is the Universe so big?
Why is the Universe so Big? The Universe is so big because it is constantly expanding, and it does so at a speed that even exceeds the speed of light. Space itself is actually growing, and this is going on for around 14 billion years or so.
What is larger than the Universe?
The universe is much bigger than it looks, according to a study of the latest observations.
