The Sun Is an Ordinary Star: How We Found Out ✛ ✎
Imagine you're proud of your family's bread recipe, and then you find out: exactly the same bread is baked all over your home village, just using local flour and starter. That's roughly what astronomers figured out about the Sun. For a long time, it was thought that our star was chemically unusual — it has fewer heavy elements than its 'twins'. The idea was that other stars 'ate' their planets and got heavier, while the Sun stayed pure.
After studying 79 solar twins, scientists used spectroscopy — a method that splits light like a rainbow to read its chemical makeup. It turned out that the key to the puzzle is the evolution of the Galaxy. After the Big Bang, the cosmos was filled only with light hydrogen and helium, and heavy elements like iron and carbon built up gradually, born in supernova explosions. Stars that formed later and in other parts of the Galaxy automatically got more of this 'seasoning'. So when scientists account for this natural variation, nearly two-thirds of the twins stop looking different from the Sun. And only very few — just a handful out of 79 — showed traces of past 'devouring' of exoplanets. So the Sun is just an ordinary star of its generation, and its chemical portrait isn't random at all but determined by its birthplace and time.
The measurement accuracy was so high that scientists could detect a change in a star's chemical makeup equivalent to one extra grain of salt in an Olympic swimming pool.
In the science fiction series 'Star Trek', they showed a star swallowing an entire planet. As it turns out, in reality, this sometimes happens, but it leaves only a barely noticeable chemical trace.