Hubble study finds dwarf galaxies retain only 11 per cent of oxygen
Researchers discovered that most oxygen produced by stars in 37 nearby dwarf galaxies appears to have been blown into space.
Researchers using the Hubble Space Telescope found that 37 nearby dwarf galaxies retained an average of only 11 per cent of the oxygen produced by their stars, according to a Times of India report. The study, published on Monday in The Astrophysical Journal, revealed that the oxygen levels in these galaxies ranged between 4 per cent and 25 per cent.
The investigation was conducted as part of the Galaxies Losing Oxygen via Winds (GLOW) project, which is funded by NASA and the National Science Foundation. Scientists used archival Hubble observations alongside data from the retired Spitzer Space Telescope and ground-based radio telescopes to examine the galaxies.
The research suggests that powerful stellar explosions create galactic winds that carry oxygen-rich material away from the galaxies. These winds appear to strip oxygen from low-mass galaxies more efficiently than previous scientific models had anticipated.
University of Utah assistant professor and co-investigator Grace Telford said the oxygen must have been inside the galaxies at some point because their stars produced it. She noted that for the oxygen to be missing, it must have been pushed out by enormous amounts of energy, such as from supernovae.
Dwarf galaxies have relatively weak gravity compared to larger galaxies, making it difficult for them to hold onto gas produced by stars. While some oxygen may remain in the circumgalactic medium, scientists have not yet determined the exact final location of the missing material.