Abstract
The dwarf irregular galaxy HIPASS J1131-31 was discovered as a source of HI emission at low redshift in such close proximity of a bright star that we call it Peekaboo. The galaxy resolves into stars in images with Hubble Space Telescope, leading to a distance estimate of 6.8 ± 0.7 Mpc. Spectral optical observations with the Southern African Large Telescope reveal HIPASS J1131-31 to be one of the most extremely metal-poor galaxies known with the gas-phase oxygen abundance 12 + log(O/H) = 6.99 ± 0.16 dex via the direct [O III] 4363 line method and 6.87 ± 0.07 dex from the two strong line empirical methods. The red giant branch of the system is tenuous compared with the prominence of the features of young populations in the colour-magnitude diagram, inviting speculation that star formation in the galaxy only began in the last few Gyr.
Original language | English |
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Pages (from-to) | 5893-5903 |
Number of pages | 11 |
Journal | Monthly Notices of the Royal Astronomical Society |
Volume | 518 |
Issue number | 4 |
Publication status | Published - 1 Feb 2023 |
Bibliographical note
Publisher Copyright:© 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.
Keywords
- galaxies: dwarf
- galaxies: irregular
- galaxies: star formation
- galaxies: individual: HIPASS J1131-31