The universe is so big that there must be a lot of mysteries that puzzle us humans - for example, why is the sky so blue? Why does the coffee on Earth always taste so good? How did everything around us - from the tiniest specks of dust to the most magnificent galaxies - come into being? Recently, scientists have discovered a breakthrough clue that seems to provide the first definitive clue to the origins of our foggy universe, unravelling a corner of the origin of matter in the universe. It is like putting together a super-complex jigsaw puzzle of the universe, and finally, a “key piece of the puzzle” has surfaced.

Our human curiosity about the universe is akin to exploring our family history: we want to know “where we came from”, not just “where we are now”. Many people believe that the universe began with the “Big Bang”, also known as the “Big Bang Theory”, but the question is, how did the explosion make these substances from nothing to something, from simple to complex formation? In the long years, how has the matter gone from some basic atoms into such a rich and colourful world now? It's like when you look at the cell phones and computers of today and can't help but ask, “How did this thing get from its original pile of circuit boards, metal and plastic to what it is now?”.

Scientists have found the “first evidence” of the Big Bang - a sign of “first-generation matter” from the universe. It's like finding ancient fossils that prove some form of life once existed. If the Big Bang theory is like an epic of the universe, then these faint signals are like the first chapter in the book, revealing how the matter of the universe evolved from simple elementary particles to the complexity we see today.

The CMB is like the “hot air” left over from the Big Bang, and these microwave signals are like the sound of the universe as a “baby”, which has travelled for billions of years and eventually reached our instruments. Scientists have analysed these microwave signals through advanced telescopes and found unusual fluctuations in them, which are, in fact “evidence” that the universe began to form matter in the early stages after its birth. These fluctuations are the equivalent of “old photographs” of the universe, fuzzy but enough to give us a glimpse of history.

It's like looking at a very old family photo, where you're blurry and even a little faded, but you can still see what you looked like when you were a kid. These signals in the cosmic microwave background radiation are snapshots of the universe from “infancy” to “adolescence”, and although the picture is not perfect, it gives us a very valuable clue. Of course, the task of scientists is not only to look at these “old photos”. They also need to extrapolate these microwave signals to calculate how the matter of the universe was distributed and how it evolved during that period (about 13.8 billion years ago). Through these calculations, scientists finally have more evidence about how matter coalesced from the most basic particles into its current complex structure. It's like piecing together the story of our ancestors through photographs, diaries and evidence.

The “ID” of the universe has finally been found! And we can learn more about the secrets of where we came from. The door to the universe has just been opened, and we still have a lot of “cosmic stories” to explore. It gives us a clearer picture of the history of the universe. The Universe is no longer that lofty, invisible and unattainable “pavilion in the sky”, it is beginning to become more traceable and understandable.

（Writer：Lily）