Located almost a billion light-years away, IC 1101 is the single largest galaxy that has ever been found in
About the Universe
Our Sun is one of at least 100 billion stars in the Milky Way, a spiral galaxy about 100,000 light-years across. The stars are arranged in a pinwheel pattern with four major arms, and we live in one of them, about two-thirds of the way outward from the center.
One such estimate says that there are between 100 and 200 billion galaxies in the observable universe. Other astronomers have tried to estimate the number of 'missed' galaxies in previous studies and come up with a total number of 2 trillion galaxies in the universe.
But the size is right—IC 1101 gargantuan. At an estimated 5.5 million light-years wide, over 50 Milky Ways could fit across it! And considering it takes our Solar System about 225 million years to complete a single revolution around the Milky Way… well…
In the case of Ton 618, the enormous Lyman-alpha nebula surrounding it has the diameter of at least 100 kiloparsecs (320,000 light-years), twice the size of the Milky Way.
Bottom line: The Local Group of galaxies consists of three large galaxies – the Andromeda Galaxy (biggest), our Milky Way (2nd-biggest) and the Triangulum Galaxy (3rd biggest) – along with 50 or so much-smaller dwarf galaxies.
It is estimated that there are roughly 200 billion galaxies (2×1011) in the observable universe. Most galaxies are 1,000 to 100,000 parsecs in diameter (approximately 3,000 to 300,000 light years) and are separated by distances on the order of millions of parsecs (or megaparsecs).
The light that travels the longest gets stretched by the greatest amount, and the object that emitted that light is now at a greater distance because the universe is expanding. We can see objects up to 46.1 billion light-years away precisely because of the expanding universe.
The scientists have estimated their current location, due to the expansion of the universe as 46.5 billion light years away, hence the diameter of the visible universe is 93 billion light years. This means that the farthest galaxies moved 30 billion light years away in 13.8 billion years.
Astronomers recently reported witnessing galaxy death for the first time. They used the Atacama Large Millimeter/Submillimeter Array (ALMA) telescopes in the Chilean desert to observe galaxy ID2299. They noticed that the galaxy is losing so much gas that it will soon go dark when it runs out of fuel for stars.
Live Fast, Die Young
Why these galaxies stopped forming stars so early is still a puzzle. These dead galaxies appear to remain dead even after 11 billion years, in the present-day universe.
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.
Milky Way Galaxy | AMNH. The Milky Way is the galaxy in which our Solar System lives. There are more than 200 billion stars in our spiral galaxy, and our Sun is just one of them.
An incredible number
By measuring that starlight – specifically, its color and brightness – astronomers can estimate how many stars our Galaxy holds. With that method, they discovered the Milky Way has about 100 billion stars – 100,000,000,000.
Because space isn't curved they will never meet or drift away from each other. A flat universe could be infinite: imagine a 2D piece of paper that stretches out forever. But it could also be finite: imagine taking a piece of paper, making a cylinder and joining the ends to make a torus (doughnut) shape.
For most space objects, we use light-years to describe their distance. A light-year is the distance light travels in one Earth year. One light-year is about 6 trillion miles (9 trillion km). That is a 6 with 12 zeros behind it!
Light-year is the distance light travels in one year. Light zips through interstellar space at 186,000 miles (300,000 kilometers) per second and 5.88 trillion miles (9.46 trillion kilometers) per year.
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.
NASA estimates that there are at least 100 billion planets in our Milky Way alone. Others estimated that the Milky Way galaxy might have anywhere between 100 to 200 billion planets.
Because looking 15 billion light-years away means looking to a time before the universe existed. Why can't we see a galaxy 15 billion light- years away? A. Because no galaxies exist at such a great distance.
“The six galaxies we found are more than 12 billion years old, only 500 to 700 million years after the Big Bang, reaching sizes up to 100 billion times the mass of our sun. This is too big to even exist within current models.
This majestic spiral galaxy might earn the nickname the "Godzilla galaxy" because it may be the largest known in the local universe. The galaxy, UGC 2885, is 2.5 times wider than our Milky Way and contains 10 times as many stars.
Additionally, the James Webb Space Telescope confirmed the existence of another galaxy named JADES-GS-z10-0, which was first observed by the Hubble Space Telescope and dates back to 450 million years after the Big Bang.
The biggest star in the universe (that we know of), UY Scuti is a variable hypergiant with a radius around 1,700 times larger than the radius of the sun. To put that in perspective, the volume of almost 5 billion suns could fit inside a sphere the size of UY Scuti.