Science & Tech · Science & Environment · 9 hrs ago
Nearby Dwarf Galaxies Hold Only 15% of Their Star-Made Oxygen
Researchers used Hubble to study 37 nearby dwarf galaxies, which are smaller than galaxies such as the Milky Way.
They found that only about 15% of the oxygen made by stars remains inside these galaxies, mostly in their gas.
Oxygen helps scientists trace how galaxies build and distribute the elements that form planets.
Radiation from massive stars and supernova explosions pushes oxygen-rich gas out over time.
The galaxies’ weaker gravity makes it easier for them to lose gas than larger galaxies do.
Much of the missing oxygen may now be in gas around the galaxies or farther out between galaxies.
The GLOW project is combining telescope observations to study where this gas goes and how elements move between galaxies and space around them.
Researchers using Hubble studied 37 nearby dwarf galaxies and found that most of the oxygen produced by their stars is no longer inside them.
Typically, only 15 percent of that oxygen remains in the galaxies today, mostly in their gas.
The researchers say radiation from massive stars and supernovae drives oxygen-rich gas out over time.
The missing oxygen is likely in gaseous halos around the galaxies and may have traveled into intergalactic space.
The findings were reported in a paper in The Astrophysical Journal.
- Who
- Researchers studying nearby dwarf galaxies, including paper co-author Grace Telford of the University of Utah.
- What
- The study found that typically 15 percent of the oxygen produced by stars in low-mass galaxies remains inside them.
- When
- The article was published on 2026-11-09. The study date is not stated.
- Where
- In 37 nearby dwarf galaxies.
- Why
- The researchers say radiation from massive stars and supernovae drives oxygen-rich gas out of the galaxies.
This story does not have two clearly opposing sides.
Researchers used Hubble observations to study 37 nearby dwarf galaxies.
The team reported that typically 15 percent of the oxygen produced by stars remains inside the galaxies.
- Galaxies studied
- 37 nearby dwarf galaxies
- Oxygen retained
- Typically 15 percent of the oxygen produced by stars
- Main instruments
- Hubble Space Telescope, retired Spitzer Space Telescope, Very Large Array and Australian Telescope Compact Array
- Paper journal
- The Astrophysical Journal
- Project
- Galaxies Losing Oxygen via Winds (GLOW)
What people are saying
We found that typically 15 percent of the oxygen produced by stars in these low-mass galaxies is still found inside those galaxies today: mostly in their gas, but small fractions are also in the stars and dust
The explanation is that energetic radiation from massive stars and their deaths as supernovae drive oxygen-rich gas out of the galaxies over time