... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. December 18, 1999 . Irregular Galaxy Sextans A . ... Their newly formed, bright, blue star clusters found along beautiful, symmetric spiral arms are guaranteed to attract attention. But small irregular galaxies form stars too , like this lovely, gumdrop-shaped galaxy, Sextans A . ... About APOD > . ...