Astronomers have spent decades hunting for the oldest stars in the universe. A certain star has left them puzzled. It sits around 190 light-years away. This is close enough to study this star in detail. Its light is brimming with secrets of the early universe. When NASA aimed the Hubble Space Telescope at it, what it revealed was astonishing.
A star in the cosmos that has experts at NASA puzzled
Early calculations put the star’s age as being older than the universe itself. That cannot be right, but the numbers kept suggesting this. Scientists found themselves in an odd position when it comes to this star. What exactly is going on with it?
HD 140283, better known as the Methuselah star, earned its nickname for a reason. It is comprised of almost no metals. This makes sense for a star born just after the Big Bang, before stars had the chance to make heavier elements. The atmosphere of this star has no metals in either; it’s a bit like a living fossil from the earliest phases of the universe. It is bright and not too far away. Because of this, experts can measure the age of this star more accurately than other ancient stars. This is exactly what has sparked the confusion that surrounds this cosmic find.
How can the Methuselah star be older than the universe?
The numbers don’t really add up, as this star can’t be older than the universe. Hubble’s data suggested that the Methuselah star is around 14.46 billion years old, give or take 800 million years. The universe is only 13.8 billion years old. How, then, can the Methuselah star be older than the universe itself? This makes no sense.
The real issue is not with the Methuselah star but rather with how difficult it is to measure the age of ancient stars like it. Estimates come with a margin of error. The Methuselah star is one of those with a wide enough margin that its birth must fall safely within the first few hundred million years after the Big Bang. So, no, it is not older than the cosmos.
The Methuselah star is not older than the universe, but it is still quite the cosmic find
It is hard to model stars with almost no metal in them. Pinning down their distance is also a challenge when stars are not in a cluster. The Methuselah star is special because it is untouched. Stars that old are usually scarred by collisions with other stars, and sometimes these get eaten away at by gas, or they simply just fade away. This particular star is, for the most part, as it has always been, which experts find to be rather peculiar.
It is somewhat of a snapshot from when the universe was made up of a few elements like hydrogen, helium, and lithium, for example. Theories around how the first stars came to form can now be tested better by studying the Methuselah star. This is a great moment for experts in this field.
What studies of the Methuselah star might reveal to experts at NASA and the world of astronomy in general?
How stars were once formed can now be looked at in more detail thanks to the Methuselah star. How heavier elements started appearing and how fast the universe expanded can now also be looked at more closely, thanks to this find. This will provide experts with a wealth of data as they continue to explore the universe.
The Hubble Space Telescope has been able to provide sharper measurements of stars like this. Astronomers have improved models of the age of the Methuselah star. It is now clear to see that this is one of the oldest stars we have ever found in the universe. It is, however, not older than the universe itself. It does show that stars formed quickly after the Big Bang and that some of those stars remain today.