If stars are like houses, then galaxies are like cities complete of homes. Scientists estimate there are 100 billion stars in Earths galaxy. If you might zoom out, method beyond Earths galaxy, those 100 billion stars would mix together– the method lights of city structures do when seen from an airplane.
If you might watch for long enough, over millions of years, it would look like brand-new space is slowly being included between all the galaxies. If you could keep going out, as far as you wanted, would you just keep passing by galaxies forever?
Galaxies, stars, and worlds
At the start of your trip through area, you may acknowledge a few of the sights. The Earth belongs to a group of worlds that all orbit the Sun– with some orbiting comets and asteroids blended in, too.
A familiar area.
You may know that the Sun is in fact simply a typical star, and looks larger and brighter than the other stars only because it is more detailed. To get to the next nearby star, you would need to travel through trillions of miles of space. If you could ride on the fastest space probe NASA has ever made, it would still take you thousands of years to arrive.
If stars are like houses, then galaxies resemble cities full of homes. Researchers approximate there are 100 billion stars in Earths galaxy. If you could zoom out, method beyond Earths galaxy, those 100 billion stars would blend together– the method lights of city structures do when viewed from an airplane.
Recently astronomers have found out that many or perhaps most stars have their own orbiting worlds. Some are even like Earth, so its possible they may be house to other beings also questioning whats out there.
This packed image taken with the Hubble Space Telescope showcases the galaxy cluster ACO S 295, as well as a jostling crowd of background galaxies and foreground stars. Credit: ESA/Hubble & & NASA, F. Pacaud, D. Coe
You would need to travel through millions of trillions more miles of space just to reach another galaxy. The majority of that space is nearly totally empty, with just some stray molecules and tiny mysterious invisible particles researchers call “dark matter.”
Utilizing huge telescopes, astronomers see millions of galaxies out there– and they just keep going, in every instructions.
If you might expect long enough, over countless years, it would appear like brand-new space is gradually being included in between all the galaxies. You can imagine this by thinking of tiny dots on a deflated balloon and then considering blowing it up. The dots would keep moving further apart, simply like the galaxies are.
Is there an end?
If you could keep going out, as far as you wanted, would you simply keep passing by galaxies forever? Exist an unlimited number of galaxies in every instructions? Or does the whole thing eventually end? And if it does end, what does it end with?
These are questions researchers do not have guaranteed answers to yet. Many think its likely you would simply keep passing galaxies in every direction, permanently. Because case, deep space would be unlimited, with no end.
Some researchers believe its possible deep space might ultimately wrap back around on itself– so if you might just keep going out, you would one day return around to where you started, from the other direction.
One way to consider this is to envision a world, and envision that you are a creature that can move only on the surface. If you begin walking any direction, east for example, and simply keep going, eventually you would come back to where you started. It would imply it is not considerably big– although it would still be bigger than you can picture if this were the case for the universe.
You could never get to the end of the universe or space. Researchers now consider it not likely deep space has an end– a region where the galaxies stop or where there would be a barrier of some kind marking completion of space.
But no one knows for sure. How to address this concern will need to be determined by a future scientist.
Written by Jack Singal, Associate Professor of Physics, University of Richmond.
This post was first published in The Conversation.
It can stretch your mind to contemplate whats truly out there.
Right above you is the sky– or as scientists would call it, the environment. It extends about 20 miles (32 kilometers) above the Earth. Floating around the environment is a mix of particles– little bits of air so little you take in billions of them each time you breathe.
Above the environment is space. Its called that because it has far fewer molecules, with lots of empty space between them.
Have you ever questioned what it would be like to take a trip to external space– and then keep going? There are some things we dont understand yet, like whether area simply goes on forever.