The Oldest Things in the Universe
The universe is extremely old, 13.8 billion years old to be precise. With the old and wise universe also comes the old and wise within. If I were to tell you that something 13 billion light years away existed, or if something older than time itself existed, would you believe me?
In this specific article, we will dive into the oldest things in the universe, some of these items you may never have heard of, while others may be so iconic that nearly everyone knows it. Starting from number 5 and working our way to number 1, we realize that we will mainly look at mega structures rather than individual stars.
At number 5 we have the one and only Milkyway galaxy. The Milkyway is one of the first galaxies created, being born only 250 million years after the big bang making it 13.51 billion years old. After all this time, it has grown to be our home galaxy and where we stand in space. Despite the Milkyway’s old age, it only has a diameter of 100,000 light years. Don’t get me wrong, the Milkyway is huge! At an averagely large galaxy, it is bigger than nearly 40% of the galaxies in the universe!
Older than the Milkyway, we come up and view Sagittarius A, the supermassive black hole in the center of the Milkyway galaxy. A fact of the astronomical world states that every galaxy is formed from some strong force that causes large amounts of stellar mass to orbit that object. That object just so happens to be Sagittarius A. Sagittarius is the supermassive black hole at the center of the galaxy. This black hole has a diameter of around 27 millions miles, a surprisingly small size right? Well besides the size shaming, how old is it? Well scientists don’t really know, but we can compare it to the Milkyway, as the Milkyway revolves around this powerful force, we assume that this black hole is nearly the same age. The very probable theory is that this black hole is around 13.6 billion years old, being born only 200 million years after the big bang!
Yet the list doesn’t stop. Out of the top 3, we have the first galaxy ever created. The galaxy called GN-z11 has been under heavy argument of how old it is, as some sources state that it was born only 400 million years after the big bang, making it nearly the same age as the Milkyway, but majority of sources claim that this universe was created 200 million years after the big bang making this galaxy 13.7 billion years old. GN-z11 is approximately 31 billion lightyears away from the Earth. And as common knowledge in terms of astronomy, the further something is away from your location, the older it tends to be. This was and is the case for GN-z11. But with GN-z11 also comes the addition of many, many old stars.
GN-z11 is red in this picture because, of how far away it is, it’s light becomes infared, AKA not visible to the human eye.
In number 2 is one of the most disregarded and underrated stars ever, SMSS J031300.36−670839.3. Despite its long name and unpopularity, it is a very important star. Known to be the second star to ever be made in the universe has surprisingly fallen into the hands of the Milkyway galaxy and has been moving in the direction of Earth, and over time has floated so close that astronomers have found this star to be only 6,000 lightyears away from Earth (more details on how they find the age and distance of a star in a separate article!). This star, informally called SMSS J0313-670839, has been predicted to have been born only 150 million years after the big bang, making this star 13.7-13.8 billion years old!
Finally, last but certainly not least is the ultimate star, the oldest star ever located only 109 lightyears from Earth is HD-140283, nicknamed Methuselah. Methuselah is a subgiant star that has managed to survive for over 13.8 billion years due to its population called Population II, types of stars called metal-poor stars. Population II stars are stars that tend to be older and less luminous, letting them live on for billions of years. You can search for more info about population I and II stars another time. Anyway, Methuselah is so old that astronomers hypothesize that this star was born only 50 millions years after the big bang! And just like SMSS, it has managed to slowly float and find a young Milkyway galaxy.
And that’s it! A top 5 list including the landmarks of the universe showing just how old everything is. This article has been rather fun to make as it has been a blast to research the mind-blowing facts about stars and galaxies. That’s it for now! Next time on the Astron.
