The atoms that make up your body underwent a fascinating cosmic journey before ending up in your body.
Contrary to previous beliefs, most of these atoms, including the carbon that forms the backbone of our being, likely spent millions of years outside the Milky Way, riding a cosmic “conveyor belt” before returning to our galaxy and eventually becoming part of us.
This revelation stems from the discovery of the circumgalactic medium, a vast network of cosmic currents that transport matter between galaxies. While it was known that heavier elements like oxygen and iron could be expelled from galaxies by supernovae and then carried back by these currents, it was previously thought that carbon, being lighter, was unable to make this journey. However, new research using data from the Hubble telescope has shown that carbon is not only present in these intergalactic currents but is also one of the most abundant elements. This means that the carbon in our bodies, along with other elements, likely spent a significant amount of time outside the Milky Way before being incorporated into the solar system and eventually into us.
This discovery could help us understand galactic evolution. The circumgalactic medium acts as a recycling system, allowing galaxies to continuously form new stars by drawing in matter expelled from others. Understanding how this cosmic conveyor belt functions will help scientists unravel the processes that drive star formation and ultimately determine the fate of galaxies. So, the next time you look at your hand, remember that the atoms within it have embarked on an epic intergalactic journey, traveling vast distances and enduring cosmic forces before becoming a part of you.
Read more on these findings at The University of Washington
