‘Cosmic conveyor belt’: Your body’s carbon spent 400,000 light-years in space

Produced by: Manoj Kumar

Star origins

Life’s foundation begins in stars. Carbon, oxygen, and iron are forged in their fiery cores and ejected into space during supernova explosions, scattering the elements necessary for planets, moons, and life itself.

Representative pic

Cosmic conveyor

These elements don’t vanish. Samantha Garza, a doctoral researcher at the University of Washington, explains they ride massive galactic currents, known as the circumgalactic medium, looping in and out of galaxies like a cosmic conveyor belt.

Galactic recycling

Garza describes the circumgalactic medium as a “giant train station,” where elements ejected by dying stars are stored temporarily before returning to form new stars, planets, and even future life. It’s the universe’s ultimate recycling program.

Representative pic

Carbon highways

The research, led by Garza, reveals that carbon—a cornerstone of life—travels vast distances, extending up to 400,000 light-years from its origin galaxy. This journey provides the raw materials for celestial creations like Earth.

Representative pic

Reservoir of life

According to co-author Jessica Werk, also at the University of Washington, the circumgalactic medium serves as a reservoir for essential elements like carbon and oxygen, enabling galaxies to sustain star formation and support life cycles.

Cycle collapse

This recycling system doesn’t last forever. Garza’s team suggests that a slowing of this cosmic process might explain why galaxies eventually stop forming stars, transitioning into quiet, lifeless cosmic deserts over billions of years.

Representative pic

Hubble’s discovery

Using the Hubble Space Telescope’s Cosmic Origins Spectrograph, the team observed quasars’ light passing through this medium, uncovering large amounts of carbon and oxygen—elements critical to the galactic life cycle.

Intergalactic journeyhabits

The research hints that the carbon in your body likely spent time drifting beyond our galaxy before returning to form Earth, a vivid reminder of the interconnectedness of life and the cosmos.

Representative pic

Future exploration

Garza and Werk hope to study other galaxies’ circumgalactic mediums to determine why some lose their fuel for star formation. These insights could redefine our understanding of the universe’s evolution and our place within it.