The expansion of the Universe is the everlasting phenomenon that occurs due to several factors. The first one is the Big Bang, the dead-end for how far scientists can measure. Nobody knows for sure what existed before the Big Bang, if there was anything. The Universe is also expanding due to the Dark Energy that causes the expansion to accelerate.
Scientists had been shocked to conclude that the Universe is getting larger at an accelerated rhythm. This was contrary to what they were expecting, as they believed the expansion should slow down because of the effects of gravity. When you throw a ball up into the air, it will ultimately slow down and come back because of the effects of gravity. The Universe’s expansion should behave in a similar way, as astrophysicists once thought.
How fast is the Universe expanding
Scientists had long been disagreeing with each other when it comes to the expansion speed of our Cosmos. A new estimate that came with the help of the Atacama Cosmology Telescope (aka ACT) is there to deepen the mystery even more. ACT observed the cosmic microwave background, which is the light sent throughout the Cosmos shortly after the Big Bang 13.7 billion years ago. Therefore, the conclusion is that our Universe is expanding a rate of around 67.9 kilometers per second for each megaparsec. This is equivalent to about 3 million light-years.
The scientists involved published their findings in two papers for arXiv.org.
But many other questions remain unanswered when it comes to understanding how the Universe works. What triggered the Big Bang in the first place? How did the laws of physics come into existence? If the Universe is indeed finite, what exists beyond its boundaries? Finding objective answers to such questions seems like the biggest challenge in astrophysics. However, the good news is that scientists never stop searching for answers.