Allāh subhanahu wa ta'ala asked you questions.
Which one is bigger , more difficult creation ? The tangled web of 200 billion galaxies or human beings?For logical reasoning, let's consider some points. What does the sky contains; trillions of stars, sun, planets, galaxies,milky ways, Andromeda?
The Milky Way Galaxy
It is very difficult to count the number of stars in the Milky Way from our position inside the galaxy. Our best estimates tell us that the Milky Way is made up of approximately 100 billion stars. These stars form a large disk whose diameter is about 100,000 light years. Our Solar System is about 25,000 light years away from the center of our galaxy – we live in the suburbs of our galaxy. Just as the Earth goes around the Sun, the Sun goes around the center of the Milky Way. It takes 250 million years for our Sun and the solar system to go all the way around the center of the Milky Way.
Read a NASA Blueshift blog post about how many stars there are in the Milky Way
We can only take pictures of the Milky Way from inside the galaxy, which means we don't have an image of the Milky Way as a whole. Why do we think it is a barred spiral galaxy, then? There are several clues.
The first clue to the shape of the Milky Way comes from the bright band of stars that stretches across the sky (and, as mentioned above, is how the Milky Way got its name). This band of stars can be seen with the naked eye in places with dark night skies. That band comes from seeing the disk of stars that forms the Milky Way from inside the disk, and tells us that our galaxy is basically flat.
Several different telescopes, both on the ground and in space, have taken images of the disk of the Milky Way by taking a series of pictures in different directions – a bit like taking a panoramic picture with your camera or phone. The concentration of stars in a band adds to the evidence that the Milky Way is a spiral galaxy. If we lived in an elliptical galaxy, we would see the stars of our galaxy spread out all around the sky, not in a single band.
Another clue comes when astronomers map young, bright stars and clouds of ionized hydrogen in the Milky Way's disk. These clouds, called HII regions, are ionized by young, hot stars and are basically free protons and electrons. These are both important marker of spiral arms in other spiral galaxies we see, so mapping them in our own galaxy can give a clue about the spiral nature of the Milky Way. There are bright enough that we can see them through the disk of our galaxy, except where the region at the center of our galaxy gets in the way.
There has been some debate over the years as to whether the Milky Way has two spiral arms or four. The latest data shows that it has four arms, as shown in the artist's illustration below.
Additional clues to the spiral nature of the Milky Way come from a variety of other properties. Astronomers measure the amount of dust in the Milky Way and the dominant colors of the light we see, and they match those we find in other typical spiral galaxies. All of this adds up to give us a picture of the Milky Way, here are billions of other galaxies in the Universe. Only three galaxies outside our own Milky Way Galaxy can be seen without a telescope, and appear as fuzzy patches in the sky with the naked eye. The closest galaxies that we can see without a telescope are the Large and Small Magellanic Clouds. These satellite galaxies of the Milky Way can be seen from the southern hemisphere. Even they are about 160,000 light years from us. The Andromeda Galaxy is a larger galaxy that can be seen from the northern hemisphere (with good eyesight and a very dark sky). It is about 2.5 million light years away from us, but its getting closer, and researchers predict that in about 4 billion years it will collide with the Milky Way. , i.e., it takes light 2.5 million years to reach us from one of our "nearby" galaxies. The other galaxies are even further away from us and can only be seen through telescopes.
Taken from official website of NASA
O company of jinn and mankind, if you are able to pass beyond the regions of the heavens and the earth, then pass. You will not pass except by authority [from Allah ].
Thereafter return the gaze, again and again, (Literally: recurring twice) the gaze turns over to you spurned, and it (becomes) regretfully most weary.
And indeed We have already adorned the lowest heaven with lamps/stars and made them outcast (meteorites) for Ash-Shayatin (The ever-vicious "ones", i.e., the devils) and We have readied for them the torment of the Blaze. 67:3-5
Verily, We have decorated the nearest sky/ heaven with an adornment, the stars, 37:6
O company of jinn and mankind, if you are able to pass beyond the regions of the heavens and the earth, then pass. You will not pass except by authority [from Allah ]
The Universe Is Directionless, Study Finds
First Published 3 years ago
This map, produced using data collected by the Planck satellite, shows a map of the light left over from the big bang. If the universe were not isotropic, scientists think they would find evidence in maps like this one. (Image credit: ESA/Planck Collaboration.)The universe, it turns out, looks the same in every direction.Of course, this isn't true on a "small scale" — the stars, galaxies, dark matter and interstellar gas that fill the universe are strewn about and clumped together in unique ways. But on a much size scale encompassing the entire universe, new research shows the cosmic landscape doesn't have any preferred direction — there's no axis of spin like the Earth, no massive asymmetries that would orient a cosmic traveler.
The new study appears to be the most in-depth attempt to answer this question, which confirms a long-held assumption in physics. In addition, it touches on the idea that Earth does not occupy a special place in the universe by showing that not only is no preferred location in the universe, there is no preferred direction.
Baking the universe
Some things in the universe look different depending on where you're standing when you look at them, or from which direction you view them. For example, the Milky Way galaxy is a disk that rotates around a central axis like a record on a turntable. The galaxy looks different depending on where its viewed from, so observers in different places see different things. But a galaxy is also anisotropic — that is, an observer in one location can look in different directions and will see something different. The stars located far out in the disk move faster as they whip around the center, compared with stars close to the middle. (This is true for an observer inside the galaxy or outside it).
It's that latter kind of variation that's addressed in the new research paper. If the universe looks the same no matter what direction its viewed from, it's isotropic. If it does have a large-scale dependence on direction, it's anisotropic. (Space.com)
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