Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Molecular hydrogen in the extremely metal- and dust-poor galaxy Leo P

Nature volume 642, pages 900–904 (2025)Cite this article

Subjects

Abstract

The James Webb Space Telescope (JWST) has revealed unexpectedly rapid galaxy assembly in the early Universe, in tension with galaxy-formation models1,2,3. At the low abundances of heavy elements (metals) and dust typical in early galaxies, the formation of molecular hydrogen and its connection to star formation remain poorly understood. Some models predict that stars form in predominantly atomic gas at low metallicity4,5, in contrast to molecular gas at higher metallicities6. Despite repeated searches7, cold molecular gas has not yet been observed in any galaxy below 7% solar metallicity8. Here we report the detection of rotational emission from molecular hydrogen near the only O-type star in the 3% solar metallicity galaxy Leo P (refs. 9,10) with JWST’s Mid-Infrared Instrument/Medium Resolution Spectroscopy (MIRI-MRS) observing mode. These observations place a lower limit on Leo P’s molecular gas content, and modelling of the photodissociation region illuminated by the O star suggests a compact (≤2.6 pc radius), approximately 104 M⊙ cloud. We also report a stringent upper limit on carbon monoxide (CO) emission from a deep search with the Atacama Large Millimeter/submillimeter Array (ALMA). Our results highlight the power of MIRI-MRS to characterize even small ultraviolet-illuminated molecular clouds in the low-metallicity regime, in which the traditional observational tracer CO is uninformative. This discovery pushes the limiting metallicity at which molecular gas is present in detectable quantities more than a factor of two lower, providing crucial empirical guidance for models of the interstellar medium in early galaxies.

Access through your institution
Buy or subscribe

This is a preview of subscription content, access via your institution

Access options

Access through your institution

Buy this article

  • Purchase on SpringerLink
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Warm H2 emission detected in Leo P’s star-forming region.
Fig. 2: Constraints on the warm H2 properties in Leo P.

Similar content being viewed by others

Data availability

JWST MIRI-MRS data from programme GO-3449 will be available to download from the Mikulski Archive for Space Telescopes (https://mast.stsci.edu) as of 23 May 2025. Data for ALMA Project 2013.1.00397.S are available to download from the ALMA archive (https://almascience.nrao.edu/alma-data). Results from the PDR modelling are available from the authors on request. All other data in this paper have been previously published.

Code availability

The JWST Science Calibration Pipeline is available at https://github.com/spacetelescope/jwst. The CASA software used to process the ALMA data is available at https://casa.nrao.edu. Code to measure and analyse the H2 emission line intensities, uncertainties and upper limits is available at https://github.com/ogtelford/LeoPH2MRS. The PDR modelling software is available at https://github.com/scog1234/SGPDR.

References

  1. Labbé, I. et al. A population of red candidate massive galaxies ~600 Myr after the Big Bang. Nature 616, 266–269 (2023).

    Article  ADS  PubMed  Google Scholar 

  2. Boylan-Kolchin, M. Stress testing ΛCDM with high-redshift galaxy candidates. Nat. Astron. 7, 731–735 (2023).

    Article  ADS  PubMed  PubMed Central  Google Scholar 

  3. Carniani, S. et al. Spectroscopic confirmation of two luminous galaxies at a redshift of 14. Nature 633, 318–322 (2024).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  4. Glover, S. C. O. & Clark, P. C. Star formation in metal-poor gas clouds. Mon. Not. R. Astron. Soc. 426, 377–388 (2012).

    Article  ADS  CAS  Google Scholar 

  5. Krumholz, M. R. Star formation in atomic gas. Astrophys. J. 759, 9 (2012).

    Article  ADS  Google Scholar 

  6. Schinnerer, E. & Leroy, A. K. Molecular gas and the star-formation process on cloud scales in nearby galaxies. Annu. Rev. Astron. Astrophys. 62, 369–436 (2024).

    Article  CAS  Google Scholar 

  7. Warren, S. R. et al. CARMA CO observations of three extremely metal-poor, star-forming galaxies. Astrophys. J. 814, 30 (2015).

    Article  ADS  Google Scholar 

  8. Shi, Y. et al. Oversized gas clumps in an extremely metal-poor molecular cloud revealed by ALMA’s parsec-scale maps. Astrophys. J. 892, 147 (2020).

    Article  ADS  CAS  Google Scholar 

  9. Skillman, E. D. et al. ALFALFA discovery of the nearby gas-rich dwarf galaxy Leo P. III. An extremely metal deficient galaxy. Astron. J. 146, 3 (2013).

    Article  ADS  Google Scholar 

  10. McQuinn, K. B. W. et al. Leo P: an unquenched very low-mass galaxy. Astrophys. J. 812, 158 (2015).

    Article  ADS  Google Scholar 

  11. Bolatto, A. D. et al. The state of the gas and the relation between gas and star formation at low metallicity: the Small Magellanic Cloud. Astrophys. J. 741, 12 (2011).

    Article  ADS  Google Scholar 

  12. Leroy, A. K. et al. Molecular gas and star formation in nearby disk galaxies. Astron. J. 146, 19 (2013).

    Article  ADS  Google Scholar 

  13. Hunter, D. A., Elmegreen, B. G. & Madden, S. C. The interstellar medium in dwarf irregular galaxies. Annu. Rev. Astron. Astrophys. 62, 113–155 (2024).

    Article  CAS  Google Scholar 

  14. Maloney, P. & Black, J. H. ICO/N(H2) conversions and molecular gas abundances in spiral and irregular galaxies. Astrophys. J. 325, 389–401 (1988).

    Article  ADS  CAS  Google Scholar 

  15. Wolfire, M. G., Hollenbach, D. & McKee, C. F. The dark molecular gas. Astrophys. J. 716, 1191–1207 (2010).

    Article  ADS  CAS  Google Scholar 

  16. Bolatto, A. D., Wolfire, M. & Leroy, A. K. The CO-to-H2 conversion factor. Annu. Rev. Astron. Astrophys. 51, 207–268 (2013).

    Article  ADS  CAS  Google Scholar 

  17. Bisbas, T. G., Tan, J. C. & Tanaka, K. E. I. Photodissociation region diagnostics across galactic environments. Mon. Not. R. Astron. Soc. 502, 2701–2732 (2021).

    Article  ADS  CAS  Google Scholar 

  18. Hu, C.-Y., Sternberg, A. & van Dishoeck, E. F. Metallicity dependence of the H/H2 and C+/C/CO distributions in a resolved self-regulating interstellar medium. Astrophys. J. 920, 44 (2021).

    Article  ADS  CAS  Google Scholar 

  19. Hu, C.-Y., Schruba, A., Sternberg, A. & van Dishoeck, E. F. Dependence of XCO on metallicity, intensity, and spatial scale in a self-regulated interstellar medium. Astrophys. J. 931, 28 (2022).

    Article  ADS  Google Scholar 

  20. Bialy, S. & Sternberg, A. CO/H2, C/CO, OH/CO, and OH/O2 in dense interstellar gas: from high ionization to low metallicity. Mon. Not. R. Astron. Soc. 450, 4424–4445 (2015).

    Article  ADS  CAS  Google Scholar 

  21. Bialy, S. & Sternberg, A. Thermal phases of the neutral atomic interstellar medium from solar metallicity to primordial gas. Astrophys. J. 881, 160 (2019).

    Article  ADS  CAS  Google Scholar 

  22. Roussel, H. et al. Warm molecular hydrogen in the Spitzer SINGS galaxy sample. Astrophys. J. 669, 959–981 (2007).

    Article  ADS  CAS  Google Scholar 

  23. Togi, A. & Smith, J. D. T. Lighting the dark molecular gas: H2 as a direct tracer. Astrophys. J. 830, 18 (2016).

    Article  ADS  Google Scholar 

  24. Hunt, L. K., Thuan, T. X., Izotov, Y. I. & Sauvage, M. The Spitzer view of low-metallicity star formation. III. Fine-structure lines, aromatic features, and molecules. Astrophys. J. 712, 164–187 (2010).

    Article  ADS  CAS  Google Scholar 

  25. Naslim, N. et al. Molecular hydrogen emission in the interstellar medium of the Large Magellanic Cloud. Mon. Not. R. Astron. Soc. 446, 2490–2504 (2015).

    Article  ADS  CAS  Google Scholar 

  26. McQuinn, K. B. W. et al. The Leoncino dwarf galaxy: exploring the low-metallicity end of the luminosity–metallicity and mass–metallicity relations. Astrophys. J. 891, 181 (2020).

    Article  ADS  CAS  Google Scholar 

  27. Rubio, M. et al. Dense cloud cores revealed by CO in the low metallicity dwarf galaxy WLM. Nature 525, 218–221 (2015).

    Article  ADS  CAS  PubMed  Google Scholar 

  28. Evans, C. J. et al. First stellar spectroscopy in Leo P. Astron. Astrophys. 622, A129 (2019).

    Article  CAS  Google Scholar 

  29. Telford, O. G., Chisholm, J., McQuinn, K. B. W. & Berg, D. A. Far-ultraviolet spectra of main-sequence O stars at extremely low metallicity. Astrophys. J. 922, 191 (2021).

    Article  ADS  Google Scholar 

  30. Telford, O. G., McQuinn, K. B. W., Chisholm, J. & Berg, D. A. The ionizing spectra of extremely metal-poor O stars: constraints from the only H ii region in Leo P. Astrophys. J. 943, 65 (2023).

    Article  ADS  Google Scholar 

  31. Telford, O. G. et al. Observations of extremely metal-poor O stars: weak winds and constraints for evolution models. Astrophys. J. 974, 85 (2024).

    Article  CAS  Google Scholar 

  32. McQuinn, K. B. W. et al. The ancient star formation history of the extremely low-mass galaxy Leo P: an emerging trend of a post-reionization pause in star formation. Astrophys. J. 976, 60 (2024).

    Article  Google Scholar 

  33. Aloisi, A. et al. I Zw 18 revisited with HST ACS and Cepheids: new distance and age. Astrophys. J. Lett. 667, L151–L154 (2007).

    Article  ADS  CAS  Google Scholar 

  34. Izotov, Y. I. et al. SBS 0335-052, a probable nearby young dwarf galaxy: evidence pro and con. Astrophys. J. 476, 698–711 (1997).

    Article  ADS  CAS  Google Scholar 

  35. Giovanelli, R. et al. ALFALFA discovery of the nearby gas-rich dwarf galaxy Leo P. I. H i observations. Astron. J. 146, 15 (2013).

    Article  ADS  Google Scholar 

  36. Bernstein-Cooper, E. Z. et al. ALFALFA discovery of the nearby gas-rich dwarf galaxy Leo P. V. Neutral gas dynamics and kinematics. Astron. J. 148, 35 (2014).

    Article  ADS  Google Scholar 

  37. Shi, Y. et al. Carbon monoxide in an extremely metal-poor galaxy. Nat. Commun. 7, 13789 (2016).

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  38. McKee, C. F. & Ostriker, E. C. Theory of star formation. Annu. Rev. Astron. Astrophys. 45, 565–687 (2007).

    Article  ADS  CAS  Google Scholar 

  39. Topping, M. W. et al. Searching for extremely blue UV continuum slopes at z = 7–11 in JWST/NIRCam imaging: implications for stellar metallicity and ionizing photon escape in early galaxies. Astrophys. J. 941, 153 (2022).

    Article  ADS  Google Scholar 

  40. Atek, H. et al. Most of the photons that reionized the Universe came from dwarf galaxies. Nature 626, 975–978 (2024).

    Article  ADS  CAS  PubMed  Google Scholar 

  41. Bushouse, H. et al. JWST calibration pipeline. Zenodo https://doi.org/10.5281/zenodo.6984365 (2025).

  42. Spilker, J. S. et al. Spatial variations in aromatic hydrocarbon emission in a dust-rich galaxy. Nature 618, 708–711 (2023).

    Article  ADS  CAS  PubMed  Google Scholar 

  43. Argyriou, I. et al. JWST MIRI flight performance: the Medium-Resolution Spectrometer. Astron. Astrophys. 675, A111 (2023).

    Article  CAS  Google Scholar 

  44. Law, D. R. et al. A 3D drizzle algorithm for JWST and practical application to the MIRI Medium Resolution Spectrometer. Astron. J. 166, 45 (2023).

    Article  ADS  Google Scholar 

  45. Burton, M. G., Hollenbach, D. J. & Tielens, A. G. G. Mid-infrared rotational line emission from interstellar molecular hydrogen. Astrophys. J. 399, 563–572 (1992).

    Article  ADS  CAS  Google Scholar 

  46. Roueff, E. et al. The full infrared spectrum of molecular hydrogen. Astron. Astrophys. 630, A58 (2019).

    Article  CAS  Google Scholar 

  47. Herbst, T. M. et al. A near-infrared spectral imaging study of T Tau. Astron. J. 111, 2403 (1996).

    Article  ADS  CAS  Google Scholar 

  48. Hunter, G. H., Clark, P. C., Glover, S. C. O. & Klessen, R. S. Towards the impact of GMC collisions on the star formation rate. Mon. Not. R. Astron. Soc. 519, 4152–4170 (2023).

    Article  ADS  CAS  Google Scholar 

  49. Gong, M., Ostriker, E. C. & Wolfire, M. G. A simple and accurate network for hydrogen and carbon chemistry in the interstellar medium. Astrophys. J. 843, 38 (2017).

    Article  ADS  Google Scholar 

  50. Habing, H. J. The interstellar radiation density between 912 A and 2400 A. Bull. Astron. Inst. Neth. 19, 421 (1968).

    ADS  Google Scholar 

  51. Sembach, K. R., Howk, J. C., Ryans, R. S. I. & Keenan, F. P. Modeling the warm ionized interstellar medium and its impact on elemental abundance studies. Astrophys. J. 528, 310–324 (2000).

    Article  ADS  CAS  Google Scholar 

  52. Bakes, E. L. O. & Tielens, A. G. G. M. The photoelectric heating mechanism for very small graphitic grains and polycyclic aromatic hydrocarbons. Astrophys. J. 427, 822 (1994).

    Article  ADS  CAS  Google Scholar 

  53. Wolfire, M. G., McKee, C. F., Hollenbach, D. & Tielens, A. G. G. M. Neutral atomic phases of the interstellar medium in the galaxy. Astrophys. J. 587, 278–311 (2003).

    Article  ADS  CAS  Google Scholar 

  54. Rémy-Ruyer, A. et al. Gas-to-dust mass ratios in local galaxies over a 2 dex metallicity range. Astron. Astrophys. 563, A31 (2014).

    Article  Google Scholar 

  55. Draine, B. T. et al. Dust masses, PAH abundances, and starlight intensities in the SINGS galaxy sample. Astrophys. J. 663, 866–894 (2007).

    Article  ADS  CAS  Google Scholar 

  56. Engelbracht, C. W. et al. Metallicity effects on dust properties in starbursting galaxies. Astrophys. J. 678, 804–827 (2008).

    Article  ADS  CAS  Google Scholar 

  57. Whitcomb, C. M. et al. The metallicity dependence of PAH emission in galaxies. I. Insights from deep radial Spitzer spectroscopy. Astrophys. J. 974, 20 (2024).

    Article  Google Scholar 

  58. Hu, C.-Y., Sternberg, A. & van Dishoeck, E. F. Coevolution of dust and chemistry in galaxy simulations with a resolved interstellar medium. Astrophys. J. 952, 140 (2023).

    Article  ADS  CAS  Google Scholar 

  59. Girichidis, P. et al. Physical processes in star formation. Space Sci. Rev. 216, 68 (2020).

    Article  ADS  Google Scholar 

  60. CASA Team et al. CASA, the Common Astronomy Software Applications for radio astronomy. Publ. Astron. Soc. Pac. 134, 114501 (2022).

    Article  ADS  Google Scholar 

  61. Schruba, A. et al. A molecular star formation law in the atomic-gas-dominated regime in nearby galaxies. Astron. J. 142, 37 (2011).

    Article  ADS  Google Scholar 

  62. Schruba, A. et al. Low CO luminosities in dwarf galaxies. Astron. J. 143, 138 (2012).

    Article  ADS  Google Scholar 

  63. Grenier, I. A., Casandjian, J.-M. & Terrier, R. Unveiling extensive clouds of dark gas in the solar neighborhood. Science 307, 1292–1295 (2005).

    Article  ADS  CAS  PubMed  Google Scholar 

  64. Jameson, K. E. et al. First results from the Herschel and ALMA spectroscopic surveys of the SMC: the relationship between [C ii]-bright gas and CO-bright gas at low metallicity. Astrophys. J. 853, 111 (2018).

    Article  ADS  Google Scholar 

  65. Madden, S. C. et al. Tracing the total molecular gas in galaxies: [CII] and the CO-dark gas. Astron. Astrophys. 643, A141 (2020).

    Article  CAS  Google Scholar 

  66. Astropy Collaboration et al. Astropy: a community Python package for astronomy. Astron. Astrophys. 558, A33 (2013).

    Article  Google Scholar 

  67. Astropy Collaboration et al. The Astropy Project: building an open-science project and status of the v2.0 core package. Astron. J. 156, 123 (2018).

    Article  ADS  Google Scholar 

  68. Aver, E. et al. A comprehensive chemical abundance analysis of the extremely metal poor Leoncino Dwarf galaxy (AGC 198691). Mon. Not. R. Astron. Soc. 510, 373–382 (2022).

    Article  ADS  CAS  Google Scholar 

  69. Perez, F. & Granger, B. E. IPython: a system for interactive scientific computing. Comput. Sci. Eng. 9, 21–29 (2007).

    Article  CAS  Google Scholar 

  70. Hunter, J. D. Matplotlib: a 2D graphics environment. Comput. Sci. Eng. 9, 90–95 (2007).

    Article  Google Scholar 

  71. van der Walt, S., Colbert, S. C. & Varoquaux, G. The NumPy array: a structure for efficient numerical computation. Comput. Sci. Eng. 13, 22–30 (2011).

    Article  Google Scholar 

  72. Harris, C. R. et al. Array programming with NumPy. Nature 585, 357–362 (2020).

    Article  ADS  CAS  PubMed  PubMed Central  Google Scholar 

  73. Joye, W. A. & Mandel, E. New features of SAOImage DS9. In Astronomical Data Analysis Software and Systems XII, Astronomical Society of the Pacific Conference Series, Vol. 295 (eds Payne, H. E., Jedrzejewski, R. I. & Hook, R. N.) 489 (ASP, 2003).

  74. Virtanen, P. et al. SciPy 1.0: fundamental algorithms for scientific computing in Python. Nat. Methods 17, 261–272 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  75. Ginsburg, A. et al. radio-astro-tools/spectral-cube: v0.4.4. Zenodo https://doi.org/10.5281/zenodo.591639 (2019).

Download references

Acknowledgements

Based on observations with the NASA/ESA James Webb Space Telescope obtained from the Mikulski Archive for Space Telescopes (MAST) at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Support for this work was provided by NASA through grant JWST-GO-3449 from the Space Telescope Science Institute under NASA contract NAS5-26555. O.G.T. acknowledges support from a Carnegie-Princeton Fellowship through Princeton University and the Carnegie Observatories. This research was supported in part by grant NSF PHY-2309135 to the Kavli Institute for Theoretical Physics (KITP). S.C.O.G. acknowledges financing from the European Research Council through the ERC Synergy Grant ‘ECOGAL’ (project ID 855130) and from the German Excellence Strategy through the Heidelberg Cluster of Excellence ‘STRUCTURES’ (EXC 2181 - 390900948). A.D.B. acknowledges support from the NSF under award AST-2108140. This paper makes use of Atacama Large Millimeter/submillimeter Array (ALMA) data. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan) and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. This research used NASA Astrophysics Data System Bibliographic Services, adstex and the arXiv preprint server. The following software was used in this analysis: Astropy66,67,68, iPython69, Matplotlib70, NumPy71,72, SAOImageDS9 (ref. 73), SciPy74, CASA60 and SpectralCube75.

Author information

Authors and Affiliations

  1. Department of Astrophysical Sciences, Princeton University, Princeton, NJ, USA

    O. Grace Telford

  2. The Observatories of the Carnegie Institution for Science, Pasadena, CA, USA

    O. Grace Telford

  3. Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, USA

    O. Grace Telford & Kristen B. W. McQuinn

  4. Department of Astronomy & Astrophysics, University of California, San Diego, La Jolla, CA, USA

    Karin M. Sandstrom & Ryan J. Rickards Vaught

  5. Space Telescope Science Institute, Baltimore, MD, USA

    Kristen B. W. McQuinn, Elizabeth J. Tarantino & Ryan J. Rickards Vaught

  6. Institut für Theoretische Astrophysik, Zentrum für Astronomie, Universität Heidelberg, Heidelberg, Germany

    Simon C. O. Glover

  7. Department of Astronomy, University of Maryland, College Park, MD, USA

    Alberto D. Bolatto

  8. Joint Space-Science Institute, University of Maryland, College Park, MD, USA

    Alberto D. Bolatto

Authors
  1. O. Grace Telford
    View author publications

    Search author on:PubMed Google Scholar

  2. Karin M. Sandstrom
    View author publications

    Search author on:PubMed Google Scholar

  3. Kristen B. W. McQuinn
    View author publications

    Search author on:PubMed Google Scholar

  4. Simon C. O. Glover
    View author publications

    Search author on:PubMed Google Scholar

  5. Elizabeth J. Tarantino
    View author publications

    Search author on:PubMed Google Scholar

  6. Alberto D. Bolatto
    View author publications

    Search author on:PubMed Google Scholar

  7. Ryan J. Rickards Vaught
    View author publications

    Search author on:PubMed Google Scholar

Contributions

O.G.T., K.M.S. and K.B.W.M. developed the JWST proposal. O.G.T. (PI of JWST-GO-3449) analysed the H2 emission lines in the MIRI-MRS observations of Leo P, made Figs. 1 and 2 and wrote the manuscript. K.M.S. led the design of the JWST observations and reduced the MIRI-MRS data. S.C.O.G. modelled the PDR to constrain the emitting H2 temperature and made Extended Data Fig. 1. E.J.T. reduced the ALMA data and calculated the upper limit on LCO in Leo P. A.D.B., R.J.R.V. and all authors contributed to interpretation of the results and to the manuscript.

Corresponding author

Correspondence to O. Grace Telford.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature thanks Chia-Yu Hu and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data figures and tables

Extended Data Fig. 1 PDR modelling suggests a low temperature for the detected H2.

H2 S(1) emission-weighted mean temperature (T) as a function of density (n) for our simple one-dimensional PDR models of the warm H2 in Leo P (see Methods for details). These calculations assume a slab symmetry for the emitting gas, with a thickness L = 1 pc and a uniform density as indicated in the figure. The slab is illuminated by the radiation field produced by the O star in Leo P, which has a strength of χ = 200 in Habing units50. Results are shown for three different values for the cosmic ray (CR) ionization rate: ζH = 10−19 s−1 (black line), ζH = 10−18 s−1 (blue line) and ζH = 10−17 s−1 (red line).

Extended Data Table 1 H2 rotational lines
Full size table

Supplementary information

Supplementary Information

This file contains further descriptions of the JWST MIRI-MRS observation design; the impacts of our assumptions on the warm H2 temperature and mass limits; an alternative measurement of the upper limit on LCO; and implications for Leo P’s total H2 mass and CO-to-H2 conversion factor.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Telford, O.G., Sandstrom, K.M., McQuinn, K.B.W. et al. Molecular hydrogen in the extremely metal- and dust-poor galaxy Leo P. Nature 642, 900–904 (2025). https://doi.org/10.1038/s41586-025-09115-7

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue date:

  • DOI: https://doi.org/10.1038/s41586-025-09115-7

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing