Recent star formation history of the dwarf irregular galaxy Sextans A from HST observations

R. C. Dohm-Palmer, E. D. Skillman, A. Saha, E. Tolstoy, M. Mateo, J. Gallagher, J. Hoessel, C. Chiosi, R. J. Dufour

Research output: Contribution to journalConference articlepeer-review


We obtained WFPC2, Hubble Space Telescope, photometric data of the resolved stars in the nearby (D = 1.4 Mpc) dwarf irregular galaxy Sextans A. We constructed color-magnitude diagrams (CMD) in V and I to a limit of 26 in V. The CMDs show several clearly separated populations. Most important for the recent history are He-burning stars (HeB) that are in the bluest part of the so-called "blue-loop" phase. We used these blue HeB stars as a tracer for the location of star formation over the past 700 Myr. There is an age progression between the regions of star formation, indicating the star formation may be propagating through the galaxy.

Original languageEnglish (US)
Pages (from-to)197-201
Number of pages5
JournalRevista Mexicana de Astronomia y Astrofisica: Serie de Conferencias
StatePublished - 1998
Event6th Texas-Mexico Conference on Astrophysics: Astrophysical Plasmas - Near and Far - Houston, TX, United States
Duration: Mar 6 1997Mar 8 1997


  • Galaxies: individual (Sextans A)
  • Galaxies: stellar content
  • Stars: formation


Dive into the research topics of 'Recent star formation history of the dwarf irregular galaxy Sextans A from HST observations'. Together they form a unique fingerprint.

Cite this